Issue 04 Autumn 2006

Transcription

solas news
issue 4 :: Autumn 2006 :: www.solas-int.org
in this issue...
Sea ice production, a mean of
enhancing air-sea CO2 transport
2
The decrease of the oceanic
carbon sink in the North Atlantic
Subpolar Gyre
3
Nitrous oxide and the
Atlantic Meridional Transect
programme (AMT)
4
The role of local and regional
5
environmental conditions in the
carbon fluxes of a tropical coastal zone
Where the Sahara meets the
Atlantic: First results from the
SOLAS cruise P320/1 to the
Mauritanian upwelling
6-7
8
Distributions and fluxes of CH4
and N2O in the Yangtze River Estuary
Detecting anthropogenic carbon
inventory growth in a noisy ocean
This picture was taken onboard the MV Skogafoss in Reykjavik harbour (Iceland) at the beginning of one of
the summer SURATLANT cruise (July 2004) between Iceland and Newfoundland. During this program salinity,
sea surface dissolved inorganic carbon (DIC) and total alkalinity (TA) are sampled in order to investigate
variations in the North Atlantic subpolar gyre since 1993.
Welcome to the SOLAS Newsletter
This is the fourth issue of the SOLAS
Newsletter, and most of the contributions are
targeted toward SOLAS Focus 3 science:
Air-sea flux of CO2 and other long-lived
radiatively-active gases. An Implementation
Plan for this research area has been developed
jointly with the Integrated Marine
Biogeochemistry and Ecosystems Research
(IMBER) project, and it sets out research
priorities for the two projects over the next
decade. This scientific intersection provides a
unique opportunity for the two projects to
synergistically collaborate toward common
goals. In order to facilitate international
coordination, the two projects have developed
the Joint SOLAS/IMBER Carbon Group (SIC),
and this group works closely with the
International Ocean Carbon Coordination
Project (IOCCP) to provide a framework for
oceanic carbon research coordination.
The science implementation for SOLAS and
IMBER revolves around three main areas: Carbon
inventories and fluxes, sensitivity to global
change, and the air-sea flux of N2O and CH4.
Within the Joint SOLAS/IMBER Implementation
Plan, these research foci are mapped to the
relevant SOLAS Activities and IMBER Themes and
Issues, and within each of these subsections, the
specific objectives are identified and
implementation requirements are described.
We encourage you to download a copy of the
Joint Implementation Plan and join us as we make
progress in this exciting area of air-sea interaction
and oceanic research. (To download, see:
http://www.uea.ac.uk/env/solas/SPIS/SPIS1.html)
Truls Johannessen – co-Chair, SIC, Bjerknes
Centre for Climate Research, Bergen, Norway
Arne Körtzinger – co-Chair, SIC, Institut für
Meereskunde an der Universität Kiel, Germany
surface ocean - lower atmosphere study
9
Nitrous oxide and methane
in the upwelling area off
Mauritania (NW Africa)
10
How does the Southern Ocean
Carbon Cycle respond to
changes in the Southern Annular
Mode (SAM)?
11
Focus on members of the SOLAS 12-13
Scientific Steering Committee
The western continental shelf
14-15
of India: A hotspot of anaerobic
biogeochemical transformations
including production of nitrous oxide
The dynamic of nutrients
and water cycles in Lombok
Strait, Indonesia
16-17
Anaerobic ammonium oxidation:
18
from mystery guest to global player
Particulate organic carbon
export from the North and South
Atlantic gyres: the 234Th/238U
disequilibrium approach
19
Impacts of winter storms on
air-sea gas exchange
21
plus...
• Briefs from
18 related projects
• SOLAS Special Reports
w w w. s o l a s - i n t . o r g
partner projects
ACCENT, the European Network of
Excellence on Atmospheric Composition
Change, aims at creating a forum
where scientists throughout Europe,
working in the sensitive field of changes
in atmospheric composition; with its
many societal implications, could join to
discuss science and exchange opinions
on how to proceed with research.
The Network is set out to provide a basis
on which the scientists can plan future
projects and experiments; set up new
collaborative efforts within Europe; and
then jointly extend the dialogue with
scientists and scientific organisations in
other areas of the world.
Furthermore, ACCENT wants to
optimise the interactions with policy
makers and the general public. So far,
the ACCENT activities have reached a
significant level of integration, involving
a critical mass of scientists, including 43
European ACCENT Partners and 124
worldwide Associate Institutions, which
are implementing the jointly agreed
ACCENT research schedule and priorities,
in close coordination with the main
international activities and programs.
ACCENT includes:
• A strong joint research program aimed
at producing advancement in specific
areas in atmospheric research such as:
the importance of aerosols for air
quality and climate; the biosphereatmosphere exchange; the transport
and transformation of atmospheric
constituents; and the linkages
between economics, policy-making,
Earth System analysis and atmospheric
composition change research.
Leif G. Anderson is a professor in Hydrosphere Dynamics at
the Department of Chemistry, Göteborg University, Sweden.
His scientific interest is the ocean carbon cycle with a focus
on high latitude oceans, especially the Arctic Ocean. His
research also applies chemical tracers to deduce water mass
formation and circulation.
Sea ice production, a mean of enhancing
air-sea CO2 transport
Leif G. Anderson, Department of Chemistry, Göteborg University, Sweden – contact: leifand@chem.gu.se
During a study of a fjord in southern Svalbard,
Storfjorden, in late April 2002 we observed very
high salinities in the bottom water, about 35.8
psu compared to that of the surface mixed layer
34.8 psu. The fjord bottom water had not been
ventilated since last summer and the high salinity
was a result of brine production during sea ice
formation. The high salinity bottom waters had
elevated concentrations of dissolved inorganic
carbon (DIC) and pCO2 compared to the surface
water (Fig 1), even if pCO2 throughout the water
column was well below that of the atmosphere.
This signal in DIC was not paralleled by that of
nutrients and oxygen, so it is unlikely that
biological activity is the cause of the high pCO2
levels. Instead, uptake from the atmosphere was
suggested (Anderson et al., 2004) as a result of
an efficient exchange through the surface film
during the ice crystal formation and the rapid
transport of the high salinity brine out of the
surface layer as illustrated in Figure 2.
The difference in CO2 partial pressure between
the surface water and the overlying atmosphere
is about –90 µatm (286 µatm relative to 376
ppm). This strong under saturation in the
surface water results in a gradient that will drive
• Integrating activities (i.e. a range of
new activities aimed at fostering the
necessary integration of the European
science community, such as the
creation of easily accessible data
bases; setting up shared experimental
facilities; and inter-comparison of
instruments and model execution etc.)
• Outreach tasks aimed at reaching
out to the whole of the scientific
community in Europe; raising the
standards of European research; fostering
new expertise; and creating interactive
links with policy and the public.
All information on ACCENT activities,
initiatives and implements are available
at: http://www.accent-network.org
a flux from the atmosphere into the sea, if the
conditions are favorable, such as during sea ice
production. A similar process functions for CFCs
and oxygen, but in the present study with less
effect, as their surface water concentrations
were closer to being in equilibrium with
atmospheric concentrations.
The total CO2 uptake, computed by integrating
the excess DIC down to 150 m relative to the
average DIC concentration in the top 50 m of
the profile was about 9 g C m-2. If this entire
signal was attributed to the winter season of
2001-2002, the CO2 uptake is about 25% of
that estimated into the Barents Sea, where the
latter flux is driven by both cooling and
biological primary production.
This process has not previously been considered
for the oceanic uptake of atmospheric CO2 in
high latitudes during the winter season. Our
suggested mechanism will be functioning and
efficient in taking up atmospheric CO2 in
regions of polynyas and leads if the surface
water is under-saturated with respect to CO2
during this period (as is the case for most
surface waters of the Arctic Ocean). In a world
of changing climate, larger areas are likely to
be ice free and open for sea ice production
during the fall and early winter, thus making
this process quantitatively more important.
References:
Anderson, L.G., E. Falck, E.P. Jones, S.
Jutterström, and J.H. Swift, Enhanced uptake
of atmospheric CO2 during freezing of
seawater: a field study in Storfjorden,
Svalbard, J. Geophys. Res., 109, C06004,
doi:10.1029/2003JC002120, 2004
Figure 1: Profiles of pCO2 and dissolved inorganic
carbon in Storfjorden, southern Svalbard, in April 2002
Figure 2: Schematic
illustration of the processes
driving the air-sea transport
Contacts: Sandro Fuzzi, ACCENT
Coordinator, ISAC-CNR
(coordinator@accent-network.org)
Michela Maione, ACCENT Executive
Secretary, University of Urbino
(project.office@accent.network.org)
//02
Antoine Corbière is a Ph.D. student in Oceanography (marine biogeochemistry) at
the Laboratoire d’Océanographie et du Climat: Expérimentations et Approches
Numériques (LOCEAN/IPSL). His research is focused on interannual variability of DIC,
TA, oceanic fCO2 and air-sea CO2 fluxes in the North Atlantic Ocean.
The decrease of the oceanic carbon sink in the North Atlantic Subpolar Gyre
Antoine Corbière - Laboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN/IPSL), Université Pierre et Marie Curie,
Paris, France. Contact: corbiere@ccr.jussieu.fr
The evaluation of interannual variations of
oceanic carbon sources and sinks represents an
important step for better understanding the
coupling between climate change and the
global carbon cycle. It is well observed that the
atmospheric CO2 is increasing regularly at
1.34 ± 0.54 µatm/yr since 1960. The decadal
change of pCO2 in the ocean (pCO2oc) is much
less known. In this context, long term regional
observations are crucial to detect the trends of
pCO2oc and validate the modelling approaches.
Since 1993, regular sea surface water
sampling for both hydrological and carbon
parameters has been conducted in the North
Atlantic between Iceland (64°N) and
Newfoundland (47°N) (Figure 1). DIC
(Dissolved Inorganic Carbon) and TA (Total
Alkalinity) were measured in laboratories in
the USA (1993-1997, LDEO) and France
(since 2001, LOCEAN). In this study, we
present new pCO2oc calculations based on
DIC and TA, and we focus the analysis on
the open ocean region of the North Atlantic
subpolar gyre (NASG). This region has been
well identified as a strong net CO2 sink, and
the area exhibits large interannual and
decadal variability driven by large-scale
climatic events such as the North Atlantic
Oscillation (NAO), through thermodynamics,
wind speed, biological processes, freshening
and ocean circulation changes.
For the period that was not sampled for the
carbon parameters (1997-2000), we
extrapolated the wintertime pCO2oc with a
simple robust relationship based on SST. The
calculated pCO2oc (1993-2003) showed a
Figure 1: Seawater surface sampling of carbon properties during
the SURATLANT program over the period 1993 to 2003.
gradual increase during the observational
period (Figure 2). As both DIC and TA were
relatively stable over 1993-2003, the decadal
variation of pCO2oc is likely controlled by the
rapid warming (+1.5°C over ten years)
experienced in this region since the decrease of
the NAO index in 1996. We have estimated an
increasing rate of +2.8 µatm/yr for wintertime
pCO2oc (Corbière et al., 2006). If the change of
wintertime pCO2oc is assumed to be constant
at multidecadal time scales, these results are in
good agreement with estimates based on
winter pCO2 reconstruction for 1972-1989
(~ 3.0 µatm/yr, Omar and Olsen, 2006).
We have also compared our summer
observations (1993-2003) with those
obtained in August-September 1981 during
the TTO/NAS experiment. On average pCO2oc
was lower in 1981 than during the 1990s. The
decadal trend of pCO2oc for summer (AugustSeptember) was +1.8 µatm/yr. This is in good
agreement with the value deduced from the
synthesis of pCO2 observations conducted
between 1982-1998 (Lefèvre et al., 2004).
This synthesis suggests that the carbon sink
has decreased since 1972 in the high latitude
of the North Atlantic. The origin of this
change requires further investigation to
separate the effect of primary production,
warming and advection of sea water from
temperate latitudes. Preliminary results for the
most recent cruises (2004-2006), suggest that
the pCO2oc increase is faster than in the
atmosphere. This highlights the need for
continuing long-term sea surface ocean
observations of carbon properties (DIC, TA
and pCO2) and investigating, in more detail,
the interannual and decadal variability in close
collaboration with the modelling community.
Acknowledgements
The SURATLANT Project is supported by
Institut National des Sciences de l’Univers
(INSU), and Institut Paul Emile Victor (IPEV).
Special thanks are also due to the Service
National d’Analyse des Paramètres Océanique
du CO2 (SNAPO-CO2) at LOCEAN/IPSL for DIC
and TA analysis. This work is also supported by
the French program FlamenCO2, a component
of SOLAS-France.
References
Corbière, A., et al., 2006. Interannual and
decadal variability of the oceanic carbon
sink in the North Atlantic subpolar gyre.
Tellus 57B, in press.
Lefèvre, N., et al., 2004. A decrease in the
sink for atmospheric CO2 in the North
Atlantic. Geophys. Res. Lett. 31(L07306),
doi:10.1029/2003GL018957.
Omar, A.M. and A. Olsen, 2006.
Reconstructing the time history of the airsea CO2 disequilibrium and its rate of
change in the eastern subpolar North
Atlantic, 1972-1989. Geophys. Res. Lett.
33(L04602), doi:10.1029/2005GL025425.
Figure 2: Evolution of winter pCO2oc (black dots) and summer pCO2oc in the NASG (open symbols) (1981, TTO/NAS
data; 1993-2003, SURATLANT data). The linear regressions for summer and winter are shown with dashed lines.
Dotted line identifies the trend deduced from reconstructed wintertime pCO2oc for 1972-1988. The long-dashed line
indicates the pCO2oc trend deduced from August observations for the period 1982 to 1998. For reference, the longterm atmospheric pCO2atm in the northern hemisphere is also shown.
//03
partner projects
It has recently been realised that snow
and ice are not passive caps on land and
ocean surfaces. The presence of ice can
initiate interesting chemistry and exhibits
control on the low atmospheric
composition. Two specific issues are the
photochemical production of NOx, and
other chemicals from snow, and the role
of halogens in chemistry (including
boundary layer ozone depletion) over
areas near sea-ice. Air-Ice Chemical
Interactions (AICI) is a joint task for IGAC
and SOLAS that seeks to coordinate and
extend research in this topic. It links
closely to the Ocean-Atmosphere-Sea
*Ice*-Snowpack Interactions (OASIS)
project, but with a different focus (AICI
concentrates on land and ocean; OASIS
adds a biogeochemical component).
Results from a number of campaigns were
discussed at a meeting in Grenoble in May,
along with laboratory and modelling
studies that help in interpretation of fluxes
and processes between air, snow and ice.
The meeting has led to the production of a
series of review papers covering the AICI
subject area. Plans are ongoing for a
number of projects during the International
Polar Year (IPY), with the aim of deepening
understanding and determining spatial
scales on which processes operate.
Co-Chairs: Eric Wolff (ewwo@bas.ac.uk)
Paul Shepson (pshepson@purdue.edu)
The International Geosphere-Biosphere
Programme is one of the four
international sponsors of SOLAS.
The IGBP Science and Implementation
Plan, which sets out the research
agenda for Phase II (2004-2013), has
been published as IGBP report No. 55.
IGBP´s new web site was recently
redesigned to improve its look and
functionality in line with the current
and future needs of the organization.
The new site (http://www.igbp.net)
conveys the visual identity of IGBP
and its relationship to the Earth
System Science Partnership (ESSP).
Grant Forster completed his Ph.D. in Marine Biogeochemistry at
Newcastle University in 2006, based on data that he collected on
legs 12 and 13 of the AMT programme. He is currently Research
Laboratory Manager in the Ocean Research Group at Newcastle and
his personal research interests include marine nitrogen and carbon
cycling with an emphasis on biogas production and sea-air flux.
Nitrous oxide and the Atlantic Meridional
Transect programme (AMT)
Grant Forster, Ocean Research Group, School of Marine Science & Technology, Newcastle University, UK.
Contact: grant.forster@ncl.ac.uk
Since the early 19th century the atmospheric
mixing ratio of nitrous oxide (N2O) has been
increasing, and it currently makes a significant
contribution to the radiative forcing of the
atmosphere (the greenhouse effect). The total
global source of atmospheric N2O is
approximately 23.6 – 28.3 Tg N2O yr-1, and the
surface ocean alone is thought to contribute
between 4.7 and 10.7 Tg N2O yr-1. The
uncertainty range for the surface ocean source
is clearly rather wide, estimates ranging
between 17 and 45 percent of the global total.
The Atlantic Meridional Transect programme
(AMT), a NERC-funded consortium project,
provided an ideal opportunity to collect
valuable new data on the latitudinal surface
water (0-300m) distribution and sea-to-air flux
of N2O in a range of biogeochemical provinces
ranging from oligotrophic gyres to highly
productive upwelling regions.
The N2O “plume” coincided with high NO3and low O2 concentrations, and ∆N2O
(the N2O concentration in excess of atmospheric
equilibrium) significantly correlated both
with NO3- and Apparent Oxygen Utilization
(AOU), strong evidence for a nitrification N2O
source. Estimated sea-to-air N2O emissions from
the Tropical Atlantic were 0.17 – 0.26 Tg N2O yr-1
(AMT 12) and 0.19 – 0.32 Tg N2O yr-1(AMT13).
The upper and lower boundaries of the flux
ranges derive from using the wind speed-based
transfer velocities of Liss and Merlivat (1986) and
Wanninkhof (1992) respectively. Slightly higher
N2O emissions from the eastern Tropical Atlantic
are consistent with strong upwelling off the coast
of Mauritania, where higher N2O saturations
were found in the mixed layer (~ 5 – 25ºN).
Figure 1 shows a latitudinal cross section of
percent N2O saturation (100% = atmospheric
equilibrium) in the upper 300 m of the Atlantic
Ocean along the AMT12 and AMT13 cruise
tracks. The dominant feature of both was a
seasonally persistent “plume” of high N2O
saturation at tropical latitudes (25ºN - 25ºS); the
maximum observed during AMT12 was around
400 %, at 302m (12º2’N, 32º3’W), and a similar
maximum occurred during AMT 13; 390 %
(33 nmol L-1) at 304m (20º6’N, 18º2’W).
References
This new data should aid improving our
understanding of the processes involved in
marine N2O cycling and its sea-to-air flux.
Liss, P.S., Merlivat, L. 1986. Air-sea gas
exchange rates: Introduction and synthesis. In:
Baut-Ménard, P. (Eds.) The Role of Air-Sea
Exchange in geochemical Cycling. Dordrecht,
Holland, pp 113-127.
Wanninkhof, R. 1992. Relationship between
Wind Speed and Gas Exchange over the
Ocean. Journal of Geophysical Research 97
(C5), 7373-7382.
Figure 1: Latitudinal
distribution of N2O %
saturation in the
Atlantic ocean during
AMT12 (top) and
AMT13 (bottom)
ESSP will hold an Open Science
Conference, 9-12 November 2006,
in Beijing to present progress in our
understanding of the natural and social
systems of global environmental change
and to highlight the ESSP approach.
The Conference will feature 3 plenary
sessions and 44 parallel sessions,
including about 200 talks and 1000
poster presentations.
http://www.essp.org/essp/ESSP2006/
//04
Amparo Martínez-Arroyo is a biologist with a PhD in Marine Ecology. She is a research scientist at
the Atmospheric Sciences Center, UNAM, where she leads the Atmospheric Aerosols Group.
Her studies are on the biosphere-atmosphere interactions, mainly about aquatic ecosystems in
continental, coastal and marine zones, working mainly on DMS-DMSP analysis in tropical seas.
She participates in various environmental multidisciplinary teams and is part of the Scientific
Committee of the recently created Mexican Carbon Program.
The role of local and regional environmental conditions in the carbon fluxes of
a tropical coastal zone
Martinez-Arroyo, A.1, Castro, T.1, Wences, R.2, Rojas, A.3, Mendoza, M.2, Saavedra M.I.1, Mamani, R1. Contact – marroyo@servidor.unam.mx
(1)
(3)
Centro de Ciencias de la Atmósfera, UNAM
Unidad Académica de Ecología Marina, UAG
(2)
An interdisciplinary approach will be
adopted to characterize the land-air-sea
carbon exchange behavior in a tropical
region of the Mexican Pacific coast
around 16°N-99°W (Figure 1). Three
complementary aspects will be investigated
in this project which was designed to focus
on quantification of carbon fluxes,
searching for the relative weight of human
activities and natural events over these
processes. Physical, biochemical and
socioeconomic aspects which could
influence the atmospheric carbon
geographical distribution and interannual
variability will be analyzed jointly, following
a multiple scale strategy regarding both
space and time.
The coastal zones have been recognized as
spaces with intense interaction processes.
They can act as zones of accumulation and
transport of carbon towards the ocean.
Nevertheless, the great heterogeneity of the
environmental conditions and of the impact
of human activities on the ecosystems
makes uncertain if the continental margins
must be considered sources or sinks of
carbon gases and what are the forces
driving them in one or another way.
Unidad Académica de Desarrollo Regional, UAG
Sources and sinks of carbon dioxide and
methane will be evaluated in two coastal
lagoon ecosystems and their adjacent
marine environment during different
weather conditions. Both sites are tropical
coastal lagoons sharing many natural
characteristics (i.e. climate regime, river
inputs, mangrove forest presence, open
communication with sea and similar sizes).
One (Laguna de Tres Palos) is located in a
highly urbanized area near of Acapulco,
Guerrero, Mexico. The other (Laguna de
Chautengo) is located about 200 km
southward of Acapulco, and is surrounded
by a rural environment with very different
human activities and land uses.
The main goals for the first 18 months in
each site are summarized as follows:
1) Atmospheric characterization,
looking for spatial and temporal
patterns of marine and land influences,
through meteorological observation,
physico-chemical analysis of atmospheric
composition and transport, pCO2 gradients
measurement as well as methane and
dioxide carbon emissions and uptake from
soils, water bodies and vegetation (mean
land-air fluxes, sea-air fluxes).
2) Hydrological dynamics characterization,
regarding mainly budget and transport
(circulation and mix) of carbon species
(total, particulate and dissolved organic and
inorganic carbon) in the lagoon-sea system
(land-sea fluxes).
3) Human dimension characterization by
means of the analysis of socio-economic data
regarding human population, land and natural
resources uses, and by exploring patterns,
temporal variability and potential changes
(scenarios), as well as identification of human
activities related with the atmospheric carbon.
The experimental part of this project includes
testing the researchers’ capacity to reach an
adequate integration of the multidisciplinary
visions. In a next stage, model development
will be necessary to achieve a quantitative
understanding of the mechanisms through
which the temporal and spatial structure of
the carbon fluxes are produced as well as the
potential sources for their variation.
Scientists and students of atmospheric,
environmental and social sciences from two
academic institutions, are developing this
project in which the field phase will begin on
October 2006. The Center of Atmospheric
Sciences from the National Autonomous
University of Mexico (UNAM) and the
Academic Units of Regional Development and
of Marine Ecology from the Autonomous
University of Guerrero (UAG) invite the SOLAS
community to contribute with the project, by
direct participation or visiting as well as by
means of suggestions about specific issues.
Figure 1: The two coastal lagoon ecosystems of
Laguna Tres Palos and Laguna de Chautengo,
where a study is being carried out to determine and
compare the role of environmental condition on
carbon flux, located along the Mexican Pacific Coast
//05
partner projects
Hermann Bange is a chemical oceanographer at the IFM-GEOMAR
in Kiel. His reseach interests include the marine nitrogen cycle
with emphasis on nitrous oxide and the oceanic pathways of
climate-relevant trace gases, such as methane. He participated
in cruises in the tropical North Atlantic, the Arabian Sea, the
Mediterranean Sea and the North and Baltic Seas.
Where the Sahara meets the Atlantic: First results from
the SOLAS cruise P320/1 to the Mauritanian upwelling
Hermann W. Bange & P320/1 scientific party, Marine Biogeochemistry Res. Div.,
The Atlantic Meridional Transect
programme is an open-ocean, in-situ,
observing system that aims to improve
understanding of the structure and
functioning of marine ecosystems; the
interactions between physical, ecological
and biogeochemical processes; and the
impact of global change on the Atlantic
Ocean. Biological, chemical and physical
data are collected in order to quantify
the nature and causes of ecological and
biogeochemical variability in planktonic
ecosystems, and to assess the effects of
this variability on the biological carbon
pump and on air-sea exchange of
radiatively-active gases. The programme
began in 1995, utilising the passage of
scientific research vessels between
the UK and the Atlantic (50°N to 52°S),
southwards in September and northwards
in April each year. As well as collecting an
internally consistent set of ‘core’ ecological
and biogeochemical measurements,
AMT also provides the contextual and
educational infrastructure for UK and
international scientists and students to
participate in open-ocean cruises to
enhance their science. AMT is, thus, both
a ‘basin-scale observatory’ monitoring the
health of Atlantic Ocean ecosystems and
a ‘floating University’ training the next
generation of oceanographers. Eighteen
40-day 13,500 km cruises have been
completed so far, involving 180 scientists
from 11 countries measuring up to
70 parameters each day to produce
140 peer-reviewed publications and
contribute to 68 PhD theses.
IFM-GEOMAR, Leibniz-Institut für Meereswissenschaften, Kiel, Germany. Contact: hbange@ifm-geomar.de
At the end of March 2005 ten scientists
(Figure 1) from the Marine Biogeochemistry
Research Division of the IFM-GEOMAR and a
colleague from the “Institut Mauritanie des
Recherches Océanographiques et de Pêches”
(Nouadhibou, Mauritania) left Las Palmas
(Canary Islands) for a cruise to the upwelling
region off Mauritania. The cruise took place
from 21 March to 7 April 2005 with the
research vessel (R/V) Poseidon and was the
second of a series of German SOLAS cruises in
the tropical North Atlantic Ocean (see e.g.
Wallace and Bange, 2004).
The contrasting biogeographic provinces off
Mauritania, which are located in direct
proximity to the Sahara, form an ideal natural
laboratory to study the biogeochemical
interactions between the surface ocean and
the lower atmosphere. Due to the seasonally
meandering Intertropical Convergence Zone
(ITCZ) the Mauritanian coastal waters
experience a pronounced seasonality of the
wind-driven coastal upwelling. During the
intensive upwelling season which peaks in
February/March, the coastal region off
Mauritania was expected to be a ‘hot spot’ of
biogenic trace gas emissions and iron input
into the ocean because it is site of very high
biological productivity; upward mixing from
subsurface layers; and enhanced atmospheric
deposition of Fe-rich Sahara dust. Thus, the
major objectives of leg 1 of the 320th cruise
of R/V Poseidon (P320/1) were to investigate
the biogeochemical cycling of climate-relevant
trace gases and iron (Fe) and to study the
physical setting off Mauritania during the
peak of the upwelling season. The main
working packages included measurements of
• atmospheric and dissolved concentrations of
carbon dioxide, nitrous oxide, methane and
halocarbons (bromoform and others),
• Fe in the upper water column,
• aerosol composition (in cooperation with
A. Baker, UEA, Norwich),
• chlorophyll and other marker pigments
(with I. Peeken, IFM-GEOMAR),
• transparent exopolymer particles and
polysaccharides (with U. Passow, AWI,
Bremerhaven),
• dissolved nutrients and continuous
underway oxygen concentrations,
• water column microstructure.
Besides an extensive underway measurement
programme, 32 stations on a 0.5°x0.5° grid
were occupied in the area between 21°-17°N
and 20°-16.5°W. The cruise ended in Mindelo
(Cape Verde Islands). The data set from P320/1
The programme held a successful meeting
at the Royal Society in London in July 2006
sponsored or endorsed by the IGBP
National Committee and EUR-OCEANS.
Poster and oral presentations from the
meeting which included talks by Patrick
Holligan, Tim Jickells, Carlos Duarte, Nick
Bates and Emilio Mananon are available
from the AMT website. The Scientific
Committee for Ocean Research (SCOR)
sponsored two young researchers from
Chile and Argentina to attend this meeting
and then participate in a workshop aimed
at increasing awareness and use of the
unique decadal AMT dataset.
Papers arising from results collected on
recent AMT cruises are to be published
in two special issues of Deep-Sea
Research II in 2006 and 2007; and a
proposal to continue AMT until 2012
has been submitted and is currently
under review.
Altlantic Meridonial Transect
http://www.amt-uk.org
//06
Figure 1: P320/1 cruise participants onboard R/V Poseidon in Las Palmas in March 2005; from the left to the right: S. Grobe, C.
Smarz, H.W. Bange, G. Petrick, T. Steinhoff, F. Malien, S. Gebhardt, S. Steigenberger, B. Quack, J. Schafstall (J.O. Abed, not shown).
will be available as of May 2006, and data
requests should be submitted to the author.
As expected, intensive coastal upwelling was
found as a narrow band along the
Mauritanian coast. The upwelled waters could
be easily identified by the drop in the sea
surface temperatures from about 22°C to
about 17°C. Both enhanced nutrient and
chlorophyll a concentrations (up to 11 µg.L–1)
were associated with the upwelled waters
causing strong gradients between the open
ocean and the coastal zone. Highest
phytoplankton biomass was associated with a
dominance of diatoms in the phytoplankton
community, while in “aged” upwelled waters
prymnesiophytes and cyanobacteria tend to
dominate the algae community.
Upwelled waters originate from a depth
range of 50-300 m and are mainly fed by
the northwards flowing upwelling
undercurrent along the continental slope,
providing South Atlantic Central Water
(SACW) to the upwelling region. Dissolved
CO2, O2 and N2O in the surface layer are
clearly associated with the upwelling (Figure
2) whereas surface CH4 concentrations are
only slightly enhanced (data not shown).
CHBr3 surface concentrations are not directly
linked to the upwelled waters but are
generally enhanced towards the boundary
to the upwelling area (data not shown).
The upwelling region off Mauritania is a
strong source of atmospheric CO2 and
N2O (Figure 2). This is in line with previous
observations from other coastal upwelling
areas such as the Arabian Sea. CO2 and
N2O concentrations were mirrored by the
O2 concentrations implying that both gases
originated from remineralisation of organic
material before the waters have upwelled.
More surprising are the results of the
bromoform (CHBr3) measurements. In
contrast to our earlier hypothesis, the
upwelling waters are not a strong source
of atmospheric CHBr3. The maximum
surface water concentrations are found in
the oligotrophic waters of the open ocean.
CHBr3 showed different correlations with
phytoplankton pigments in the cold and warm
waters, suggesting various biological sources.
The emissions of CHBr3 from the upwelling
are too low to maintain the observed
atmospheric mixing ratios, which are
supplemented by additional not yet
identified coastal sources.
Currently, the results from P320/1 are
being analysed in detail and we are looking
forward to the results of the forthcoming
German SOLAS cruises to the tropical NE
Atlantic Ocean. For example, during leg 3 of
the R/V Meteor cruise 68 in July/August 2006,
the region off Mauritania will be revisited
during the non-upwelling season.
Further cruises as part of the proposed
German SOLAS contribution SOPRAN
(Surface Ocean Processes in the
Anthropocene) are in the planning stages.
partner projects
Acknowledgements
We are indebted to many land-based colleagues
for their excellent collaboration without whom
P320/1 would not have been successful.
We thank the authorities of Mauritania for
permission to work in territorial waters and
acknowledge the excellent support by the
officers and crew of R/V Poseidon. The cruise
P320/1 has received SOLAS research
endorsement and was financially supported by
the IFM-GEOMAR and the Deutsche
Forschungsgemeinschaft (DFG).
References
Wallace, D.W.R., and H.W. Bange,
Introduction to special section: Results of the
Meteor 55: Tropical SOLAS expedition,
Geophys. Res. Lett., 31, L23S01,
doi:10.1029/2004GL021014, 2004.
A compilation of 10 articles with the results
from the first German SOLAS cruise
Meteor 55 published in Geophys. Res. Lett.
http://www.agu.org/journals/ss/SOLAS1/ .
The quadrennial Symposium of CACGP
(Commission on Atmospheric Chemistry
and Global Pollution), jointly sponsored
by IGAC (International Global
Atmospheric Chemistry) and the
World Meteorological Organization
(WMO), was held between the 18th 23rd September 2006 in Cape Town,
South Africa. The theme of the
Symposium, “Atmospheric Chemistry
at the Interfaces” is detailed at
www.atmosphericinterfaces2006.co.za.
The Program consisted of 11
interdisciplinary topics illustrating the
“interfaces” theme: at atmosphereland, atmosphere-ocean, upper
troposphere /lower stratosphere,
regional-to-global chemical processes,
air-snow-ice and aerosols. There were
mini-sessions focusing on atmospheric
chemistry research in Africa: from the
IGAC-sponsored AMMA (African
Monsoon Multidisciplinary Analysis)
and DEBITS (Deposition of
Biogeochemically Important Trace
Species) and the Air Pollution
Information Network - Africa (APINA).
Special highlights of the meeting were
the Keynote Speaker, Prof. Barry Huebert
of the University of Hawaii and a
Program for Young Scientists.
Over 600 Abstracts were received for
the Symposium, which was expected to
drawn more than 600 participants. The
Program Committee has been chaired by
Mark Lawrence (Max Planck Institute for
Air Chemistry Mainz, Germany), the
IGAC Executive Office (Sarah Doherty,
Univ. Washington, Seattle, US), CACGP
President (Anne Thompson, Penn State
Univ, US), IGAC Co-Chairs S. Fuzzi
(Univ Bologna, Italy), Phil Rasch (NCAR,
US), Len Barrie (WMO AREP Head,
Switzerland) and Local Organizing Chair,
Stuart Piketh of the University of the
Witwatersrand, SA, had secured support
to ensure a strong representation of
junior scientists and participation from
developing world countries.
Contributed by Anne Thompson,
CACGP President (amt16@psu.edu)
SOLAS Open Science Conference
Figure 2: Surface distributions of (A) temperature (SST)
in °C, (B) O2 in µmol.L–1, (C) CO2 in µatm and (D) N2O in
nmol.L–1. The cruise track is indicated by locations of the
the individual underway samples: The SST, O2, CO2 data
have a 1 minute time resolution and the N2O data have
a 42 minutes time resolution. The coastline is
schematically indicated.
6-9 March 2007 - Xiamen, China
Register Now!
www.solas2007.confmanager.com
Early registration deadline 1 Dec 2006
See back page for details
//07
Dr. Guiling Zhang received her PhD in Marine Chemistry from
Ocean University of China (OUC) in 2004. She is currently an
associate professor at OUC and her research work is focused
on the biogeochemistry of trace gases (i.e. methane, nitrous
oxide and phosphine) in the seawater.
partner projects
Distributions and fluxes of CH4 and N2O in the
Yangtze River Estuary
Guiling Zhanga, Jing Zhanga,b, Jie Xua, Sumei Liua - Contact: guilingzhang@ouc.edu.cn
CARBOOCEAN - Update from the
SOLAS-endorsed EU Integrated Project
CARBOOCEAN aims at an accurate
assessment of the marine carbon sources
and sinks with special emphasis on the
Atlantic and Southern Oceans on a time
scale –200 to +200 years from now.
Being in the second year of the project’s
5 year duration, significant progress has
been made both on the modeling and the
experimental side. Measurements show,
that the air-sea difference in CO2 partial
pressure has decreased during the last 20
years. The challenge for modelers using
coupled physical-biogeochemical models
is now, to identify the reason for this
decline together with the experimentalists.
On the other hand, the CO2 airborne
fraction has stayed quite constant during
the past decades, implying that possibly
other carbon sinks may have increased in
strength in parallel. We are currently
evaluating the ability of coupled Earth
system models to reproduce the large
scale ocean carbon distribution using a
data set of ocean carbon measurements
of unprecedented scope. These issues,
together with new findings on marine
carbon cycle climate feedbacks, new data
collections, analysis results, and outreach
activities including school programmes will
be discussed on the forthcoming
CARBOOCEAN annual meeting to be held
in Gran Canaria, 4-8 December 2006.
In terms of education and outreach,
CARBOOCEAN has recently invited
16- to 17-year old pupils, and their science
teachers, to join two research cruises to
carry out several hand-on experiments.
Both teachers and students pointed out
that experience and adventure were
directly linked with information and
knowledge that would promote learning
in a very favorable way. This CarboSchools
field experience also gave them an idea of
what is meant to be a researcher.
CARBOOCEAN
http://www.carboocean.org
http://www.carboschools.org
aDepartment
of Marine Chemistry, Ocean University of China, 5 Yushan Road, Qingdao 266003, P. R. China
Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 Zhongshan
Road North, Shanghai 200062, P. R. China
bState
CH4 and N2O are important atmospheric trace
gases, which play significant roles in global
warming and atmospheric chemistry (IPCC,
2001), and the global oceans are net natural
sources of atmospheric CH4 and N2O. Although
coastal regions such as continental shelves,
estuaries and bays only occupy a small part of
the world ocean area; they appear to be
responsible for a large part of the oceanic CH4
and N2O emissions (Bange et al., 1994; 1996).
Therefore, studies on the biogeochemistry of
dissolved CH4 and N2O in coastal waters will be
helpful to estimate the contribution of oceanic
emissions to the atmospheric CH4 and N2O on a
global scale, and to predict the influence of
oceanic emissions to the global climate.
Distributions and fluxes of CH4 and N2O were
determined during two surveys on the Yangtze
River estuaries and its adjacent areas in AprilMay and November 2002. CH4 and N2O
concentrations in both the surface and bottom
waters of the study areas show apparently
seasonal variations, which are higher and more
variable in spring than in autumn. The most
conspicuous feature seen in all of the
horizontal distributions of CH4 and N2O is the
decrease of concentration along the freshwater
plume from the river mouth to the open sea.
Dissolved CH4 and N2O in the surface waters of
the mainstream and tributaries of Yangtze River
were determined during a survey in April-May
2003 and the results range from 5 to 300 nmol/L
and 102 to 482 nmol/L, respectively, for CH4 and
N2O. Based on the mean concentrations in the
mainstream and a mean discharge of Yangtze
River, total CH4 and N2O input via the Yangtze
River is estimated to be 1.24 and 1.34
(x 108) mol/yr, which indicates that the Yangtze
River is a very important source for CH4 and N2O
in the estuary and its adjacent area.
In situ incubation experiments of sediments
show that methane release rates, from two
sediments, are 2.42 and 1.91 mmol.m-2.d-1,
and the N2O release rates are 2.02 and -1.88
mmol.m-2.d-1, which indicates that sediments
can act as both a source and a sink of N2O in
the water column, while it is a net source of
CH4 in the water column. In situ incubation
experiments of the surface and bottom waters
show that biological activity in the water column
of the studied areas can act as both a source
and a sink of CH4, but it is a net source of N2O.
The estimated average CH4 fluxes using long
term wind speeds and LM86 relationship are
11.7±10.8 and 7.71±7.87 mmol.m-2.d-1 (Fig 1),
and the average N2O fluxes are 8.78±4.95 and
4.82±5.42 mmol m-2 d-1 in spring and autumn,
respectively (Fig 2). Hence the Yangtze River
estuary and its adjacent areas are net sources
of atmospheric CH4 and N2O in both spring
and autumn, and its strength appears to be
relatively higher compared to the open ocean
and the shelf region.
References:
Bange, H. W., U. H. Bartell, S. Rapsomanikis,
M. O. Andrae, Methane in the Baltic and
North Seas and a reassessment of the marine
emissions of methane, Global
Biogeochem.Cycles, 1994, 8, 465-480
Bange, H.W., S. Rapsomanikis and M.O.
Andreae, Nitrous oxide in coastal waters. Global
Biogeochem. Cycles, 1996c, 10, 197-207
IPCC, Climate Change 2001: The Scientific
Basis. Contribution of Working Group I to the
Third Assessment Report of the
Intergovernmental Panel on Climate Change?
Houghton, J.T., Y. Ding, D.J. Griggs, M.
Noguer, P.J. van der Linden, X. Dai, K.
Register Now!
See back page for details
//08
Figure 1: Distributions of atmospheric fluxes of methane
from the Yangtze River Estuary mmol·m-2·d-1
Figure 2: Distributions of atmospheric fluxes of nitrous
oxide from the Yangtze River Estuary mmol·m-2·d-1
Scott Doney is a Senior Scientist in the Department of Marine Chemistry and
Geochemistry at WHOI. After finishing graduate school from the MIT/WHOI
Joint program in 1991, he became a postdoc and, later, a scientist at NCAR,
before returning to WHOI in 2002. His interests broadly cover the intersection
of ocean circulation, biogeochemistry and ecology as well as global carbon
cycle interactions with climate.
Detecting anthropogenic carbon inventory growth in a noisy ocean
Scott C. Doney and Naomi M. Levine, Woods Hole Oceanographic Institution, Woods Hole MA USA. Contact: sdoney@whoi.edu
The uptake of atmospheric carbon dioxide
(CO2) by the ocean can, to some extent, slow
the growth of this potent greenhouse gas
arising from fossil fuel burning and land-use
change. In the late 1980s and early 1990s,
the WOCE/JGOFS CO2 Survey provided the
first, globally consistent view of the ocean
inorganic carbon system. Key results included
new data-based estimates of the distribution
and global inventory of anthropogenic carbon
in the ocean (e.g., Sabine et al., 2004). The
anthropogenic signal is a small perturbation
on top of a large, natural dissolved inorganic
carbon (DIC) background. Currently, surface
waters are elevated by 50-60 mmol/kg
relative to preindustrial levels of approximately
2000 mmol/kg. The anthropogenic signal is
mostly contained in the upper thermocline
and drops off with depth to <5 mmol/kg in
deep waters. Best estimates are that roughly a
third of all anthropogenic carbon emissions
since the beginning of the industrial
revolution have ended up in the ocean.
The WOCE/JGOFS era data also serves as an
excellent baseline for observing the uptake of
anthropogenic CO2 over time (e.g., Peng et
al., 1998). Field programs (such as
CLIVAR/CO2) are now underway to measure
changes in the ocean carbon system by
conducting repeat occupations of key basinscale transects on 5-10 year intervals
(http://ushydro.ucsd.edu/). The expected rate
of increase in anthropogenic DIC is small, from
0.5 to 1.5 mmol/kg/yr in the thermocline.
With such coarse temporal sampling,
approaches are needed to remove the effects
of mesoscale eddies and interannual variability
that would otherwise obscure the long-term
anthropogenic trend of interest (top Figure
panel). We are using numerical results from a
coupled carbon-climate model (NCAR CSM1.4; Fung et al., 2005; Doney et al., 2006) to
investigate the magnitude of natural variability
in the ocean carbon cycle and the impact of
this variability on the detection and attribution
of annual to decadal-scale ocean DIC changes.
Since modern-day DIC data include both preindustrial and anthropogenic contributions,
several different techniques have been
developed to remove the preindustrial
background and interannual variability in order
to calculate anthropogenic carbon. Specifically,
we apply two commonly used empirical
methods, the ∆C* technique and a multiple
linear regression (MLR) analysis (Wallace,
1995), to the model dataset to determine the
extent to which these methods can be used to
filter out natural variability from repeat ocean
transect data. While the ∆C* technique
performs well at low latitudes, it is unable to
remove some of the natural variability in the
ocean carbon cycle, particularly at high
latitudes (middle and bottom Figure panels).
In these regions, ∆C* overcompensates for
changes in apparent oxygen utilization (AOU)
leading to significant errors (up to ±10
mmol/kg for transects sampled a decade
apart) in the estimate of anthropogenic CO2.
The MLR analysis does a better job at
recovering the true simulated temporal change
in anthropogenic CO2; however, the MLR
approach is unable to account for changes in
DIC due to secular trends (e.g. ocean
warming) because the basic assumption of a
stationary ocean no longer holds true. In
addition, both the ∆C* and MLR techniques
can only be applied to the upper water
column (0-200m) with some caution.
Wong, D.W.R. Wallace, B. Tilbrook, F.J.
Millero, T.-H. Peng, A. Kozyr, T. Ono, and
A.F. Rios (2004): The oceanic sink for
anthropogenic CO2, Science, 305, 367-371.
Wallace, D.W.R. (1995), Monitoring global
ocean carbon inventories, Ocean Observing
System Development Panel, Texas A&M
University, College Station, TX. 54pp.
Data-based estimates of the ocean uptake of
anthropogenic carbon are essential for the
evaluation of the numerical models used for
future climate projections. We argue that
traditional hydrographic section data should
be augmented with additional information
from time-series, profiling floats (such as the
Argo array), satellite remote sensing, and
numerical hindcasts in order to best
determine ocean carbon system changes.
References
Doney, S.C., K. Lindsay, I. Fung and J. John,
2006: Natural variability in a stable 1000
year coupled climate-carbon cycle
simulation, J. Climate, 19(13), 3033-3054.
Fung, I., S.C. Doney, K. Lindsay, and J. John,
2005: Evolution of carbon sinks in a changing
climate, Proc. Nat. Acad. Sci. (USA), 102,
11201-11206, doi:10.1073/pnas.0504949102.
Peng, T.-H., R. Wanninkhof, J.L. Bullister, R.A.
Feely, and T. Takahashi (1998), Quantification
of decadal anthropogenic CO2 uptake in the
ocean based on dissolved inorganic carbon
measurements, Nature, 396, 560-563.
Sabine, C.L., R.A. Feely, N. Gruber, R.M. Key,
K. Lee, J.L. Bullister, R. Wanninkhof, C.S.
Figure: The top panel shows the
simulated rms (1σ) natural variability in
dissolved inorganic carbon (DIC) along a
north-south section in the Atlantic from
the CSM-1 coupled carbon-climate
model. The middle panel shows the
change in DIC over a 10 year period in a
simulation with anthropogenic CO2
emissions, and the bottom panel
illustrates the resulting error when the
∆C* technique is applied to estimate the
change in anthropogenic carbon.
//09
partner projects
Earlier this year, CLIVAR’s Indian Ocean
Panel published its Implementation Plan for
sustained observations
(http://eprints.soton.ac.uk/20357/01/IOP_Im
pl_Plan.pdf), one key new element of
which is a basin-scale mooring array. This
array consists of 39 surface moorings for
measurement of temperature, salinity,
currents, and basic weather variables and 5
Acoustic Doppler Current Profilers for
equatorial and coastal boundary currents.
The array is designed to resolve the most
energetic variations in the ocean as well as
interactions between the ocean and
atmosphere. Eight of the 39 surface
moorings will be enhanced for
measurements of surface flux components
in different climatic zones where
climatologies are poorly known or where
surface fluxes are critical for understanding
climate variability. These moorings will also
provide data to calibrate flux estimates
from satellite retrievals and atmospheric
model analyses. Implementation of the
array is underway with 8 moorings
deployed in the central and eastern Indian
Ocean by the Japan Agency for MarineEarth Science and Technology, NOAA’s
Pacific Marine Environmental Laboratory,
the Indian National Institute of
Oceanography and Indian Department of
Ocean Development. Completion of the
array, which is dependent on a variety of
factors such as availability of ship time and
funding levels, is scheduled for 2010. The
potential for adding biogeochemical
sensors and the research issues that can be
addressed with such measurements was
discussed at the Sustained Indian Ocean
Biogeochemical and Ecological Research
(SIBER) Workshop
(http://ian.umces.edu/siber) in October
2006. Up to date information on the array
and other elements of the Indian Ocean
Observing System (IndOOS) are at
http://www.clivar.org/organization/
indian/IndOOS/obs.php.
Sarah Gebhardt studied chemistry at Kiel University. During her
diploma thesis she set up an analytical technique to measure
hydroxylamine (NH2OH) in seawater. During P320/1 she was in
charge of the N2O/NH2OH/CH4 sampling programme. She is now
a PhD student at the MPI for Chemistry in Mainz, where she is
working on the air-sea exchange of volatile organic compounds.
Nitrous oxide and methane in the upwelling area
off Mauritania (NW Africa)
Sarah Gebhardt* and Hermann W. Bange - Forschungsbereich Marine Biogeochemie, IFM-GEOMAR, LeibnizInstitut für Meereswissenschaften, Kiel, Germany - Contact: gebhardt@mpch-mainz.mpg.de
* now at: Abteilung Chemie der Atmosphäre, Max-Planck-Institut für Chemie, Mainz, Germany.
Nitrous oxide (N2O) and methane (CH4) are trace
gases which play important roles in the chemistry
of the Earth’s atmosphere. The ocean is a major
source of N2O and a minor source of CH4.
Coastal upwelling regions have been identified as
‘hot spots’ of oceanic emissions of both gases.
During the first leg of cruise no. 320 with R/V
Poseidon (P320/1) in the upwelling area off
Mauritania (NW Africa) in March/April 2005,
atmospheric and dissolved N2O and CH4 were
measured continuously in the surface layer. The
cruise P320/1 was a pilot study for the upcoming
German contribution to SOLAS named SOPRAN
(Surface Ocean Processes in the Anthropocene).
The N2O surface distribution was closely
associated with sea surface temperature (Figure
1). Depth profiles of N2O (not shown) support the
view that N2O is accumulating in the subsurface
oxygen minimum zone and then brought to the
surface by upwelling processes. The cold, freshly
upwelled waters along the coast showed
significantly enhanced N2O concentrations.
The N2O concentrations (saturation) ranged from
about 7-8.nmol.L-1 (100-107%) in the open
ocean up to 12.nmol.L-1 (150%) in the upwelling
area. This implies that the narrow band of coastal
upwelling off Mauritania was a strong source of
atmospheric N2O. Since subsurface oxygen
concentrations were well above the threshold for
denitrification, we assume that nitrification is the
major N2O formation process off Mauritania.
In contrast to N2O, CH4 concentrations were
only weakly affected by the upwelling (Figure
1). The N2O concentrations (saturations) ranged
from about 2.0.nmol.L-1 (100%) in the open
ocean up to 2.4.nmol.L-1 (107%) in the
upwelling area. This is a rather unexpected
finding, the reasons for which are not yet clear.
Figure 1: (A) Dissolved N2O (turquoise filled circles) and
SST along 18.5°N and (B) dissolved CH4 (light brown filled
circles) and SST along 17.0°N. Black filled circles represent
sea surface temperature (SST).
In order to resolve the seasonality of the trace
gas emissions off Mauritania, further
investigations are currently ongoing (R/V
Meteor cruise M68/3 in July/August 2006,
Poseidon cruise P348 in February 2007).
Based on these surveys of the trace gases
their fluxes off Mauritania will be quantified.
This work was partly funded by the DFG.
SOLAS Special Report: 2006 Japan Society for the Promotion of Science (JSPS) Award
On 9th March 2006, a ceremony, attended by His
Imperial Highness Prince Akishino, was held at the
Japan Academy where the JSPS Prize and the Japan
Academy Medal was awarded to Dr. Shigenobu Takeda,
a member of the SOLAS community.
On the recommendation of the JSPS Prize Selection
Committee (chair, Dr. Leo Esaki), comprising of leading
researchers such as Dr. Masatoshi Koshiba and Dr. Ryoji
Noyori (Nobel Prize winners), the Japan Society for the
Promotion of Science (president, Prof. Motoyuki Ono)
chose 24 young researchers, who are expected to
become future trailblazers of scientific research in
Japan, as the recipients of the FY2005 JSPS Prize. Their
fields of research run through a spectrum from
humanities and social sciences to natural sciences.
The JSPS Prize is meant to recognize, at an early stage
in their careers, young researchers with fresh ideas who
have the potential to become international leaders in
//10
their fields, while helping to enhance their opportunities
to advance their research.
The recipients were selected for their research findings
expanding the boundaries of their academic fields.
Some topics characterizing the work of the recipients
include theories for the improvement of world’s plant
productivity; oceanic contributions to global warming
countermeasures; Japan’s first implantable blood pump
for long-term circulatory support; and protein’s role in
meiotic division of germ cells.
Dr. Shigenobu Takeda, an associate professor at the
Graduate School of Agricultural and Life Sciences, The
University of Tokyo, was awarded the JSPS prize for his
work entitled, “Studies on the Role of Iron as a Key
Nutrient Regulating Primary Production of
Phytoplankton in the Ocean”.
Dr. Shigenobu Takeda (atakeda@mail.ecc.u-tokyo.ac.jp)
Andrew Lenton is an ocean biogeochemical modeler. He recently completed his PhD at
CSIRO Marine and Atmospheric Research, Hobart, Australia, following degrees in physics
and Antarctic Studies. Currently, he is a postdoctoral researcher based at LOCEAN in Paris in
the framework of CARBOOCEAN. His research interests include global ocean
biogeochemical modeling, development of sampling strategies and understanding the
mechanisms that drive variability in the Southern Ocean.
How does the Southern Ocean Carbon Cycle respond to changes
in the Southern Annular Mode (SAM)?
Andrew Lenton1,2,3,* Richard J. Matear2,3
1.Institute for Antarctic and Southern Ocean Studies (IASOS), University of Tasmania, Australia; 2. CSIRO Marine and Atmospheric Research (CMAR),
Tasmania, Australia; 3. Antarctic Climate and Ecosystem Cooperative Research Centre (ACE CRC), University of Tasmania, Australia
* Now at: Laboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN/IPSL), Université Pierre et Marie Curie, Paris,
France. Contact: Andrew.Lenton@lodyc.jussieu.fr
The Southern Ocean, with its energetic
interactions between the atmosphere, ocean
and sea ice, plays a critical role in ventilating
the global oceans and regulating the climate
system though the uptake and storage of
heat, freshwater and atmospheric CO2. This
uptake shows large variability at interannual
and longer timescales, and this has important
implications for the global carbon budget;
therefore it is important to understand what
drives this variability to be able to predict
how it may respond to climate change.
We explore what role the Southern Annular
Mode (SAM or AAO or HLM), the dominant
mode of climate variability in the Southern
Hemisphere, has in driving interannual
annual Southern Ocean air-sea CO2 fluxes.
The SAM induces changes in the strength of
westerly winds that has been shown to
induce significant changes in ocean
circulation (Oke and England, 2004).
These changes include: (1) changes in the
strength of northward Ekman Flow and
increased upwelling along the Antarctic
Continent; (2) changes in the vertical tilt of
the isopycnals; and (3) changes in the
strength of the Antarctic Circumpolar Current
(ACC) resulting in changes in mixed layer
depth and oceanic heat transport. Present
climate change projections suggest that the
strength of the SAM will increase in future
decades. We defined the SAM as the first
temporal EOF of the 850 hPa geopotential
height anomaly following Marshall (2002).
The Southern Ocean remains one of the
most poorly carbon sampled regions
globally, particularly at the interannual and
longer timescales. Therefore, to explore
how the SAM affects the carbon cycle, we
use a prognostic Biogeochemical Ocean
Global General Circulation Model (BOGCM).
The model we used was the CSIRO Mk 3
model, driven with NCEP-R1 atmospheric
forcing and observed CO2 history following
the protocol of NOCES (OCMIP3;
http://www.ipsl.jussieu.fr/OCMIP/phase3/sim
ulations/NOCES/HOWTO-NOCES.html)
In this way we let the NCEP forcing fields
generate our interannual variability. The airsea CO2 flux and its components (wind
speed, sea surface temperature, salinity,
dissolved inorganic carbon (DIC) and
alkalinity (ALK)) are regressed against the
SAM in this study. This allows us to estimate
and quantify the response of each to the
SAM focusing on the period 1980-2000.
South of 40°S the response of the Southern
Ocean to the SAM can be divided into two
regions, north and south of the Subtropical
Front (STF; ~ 45°S; Figure). In the positive
phase of the SAM, the region south of the
STF showed a net decrease in uptake of
CO2, while north of the STF there was a net
increase. While these regions did have some
compensating effect, when integrated over
the Southern Ocean, the region south of
the STF was clearly dominant, inducing a
change in CO2 uptake of 0.15 PgC per unit
change in the SAM, significant relative to
the annual mean uptake of 0.6 PgC/yr. Over
the period 1980-2000 the SAM explains
32% of the variance in the total interannual
variability in air-sea CO2 fluxes.
Our analysis demonstrates that while the
SAM affects air-sea flux through changes in
both piston velocity and ∆pCO2, it was
primarily (90%) changes in ∆pCO2 that drove
the response of air-sea fluxes in the Southern
Ocean. Our analysis further shows that
changes in ∆pCO2 are in turn driven by
changes in the concentration of DIC in
Southern Ocean surface waters. South of the
STF, during the positive phase of the SAM,
ocean physics drove the increased supply of
DIC and ALK to surface waters; the strongest
response was associated with the Antarctic
Divergence (~64°S). The increase in ∆pCO2
due to the supply of DIC was partially offset
by an increase in ALK. North of the STF the
increase in uptake was due to solubility
changes due to sea surface cooling.
In the future, we expect that the effect of
the SAM on air-sea CO2 fluxes, in particular
the supply of DIC to the upper ocean, will
be partially compensated for by the
predicted ocean stratification due to global
warming (Matear and Hirst, 1999). Our
current research using a coupled oceanatmosphere model is aimed at exploring
and quantifying these interactions as well
as detection of the SAM response in the
observations collected in the Southern
Ocean as part of the long-term
international CO2 observational programs.
Acknowledgements
This research received support from the
Australian Commonwealth Cooperative
Research Program and the European
Integrated Project CARBOOCEAN.
References
Marshall, G.J., 2002. Trends in Antarctic
geopotential height and temperature: A
comparsion between radiosonde and NCEPNCAR reanalysis. J. Clim., 15: 659-674.
Matear, R.J. and Hirst, A.C., 1999. Climate
change feedback on the future oceanic
CO2 uptake. Tellus, 51B: 722-733.
Oke, P. and England, M.H., 2004. Oceanic
Response to Changes in the Latitude of the
Southern Hemisphere Subpolar Westerly
Winds. J. Clim., 17: 1040-1054.
Figure: The response of the Southern Air-sea CO2
fluxes to the Southern Annular Mode in its positive
phase. Positive values (red) indicate an increase in uptake.
//11
In Focus
In each issue of SOLAS news, we give you the chance to meet some of
the members of the SOLAS Scientific Steering Committee.
Gerrit de Leeuw
de
Ger ri t
Gerrit de Leeuw is a Senior Research Fellow at TNO, and visiting professor at the School
of Earth and Environment at the University of Leeds (UK). He is soon commencing a full
professorship at the University of Helsinki (UHEL)/Finish Meteorological Institute (FMI) in
the field of “Climate change and air quality monitoring using satellite and in-situ
observations”. With 25 years of experience with aerosol ground based measurements of
physical, optical and chemical properties; lidar remote sensing; and air-sea interaction, he
has published ca. 70 peer-reviewed articles in the fields of aerosols, remote sensing and
ocean-atmosphere interaction. He has also participated in 18 EU projects. He chairs the
Programme Committee for Remote Sensing of the Netherlands National Research
Foundation NWO-ALW, is a member of the SOLAS International SSC, the WCRP Working
Group on Surface Fluxes, the SOLAS IMP2 SC, of the EU FP6 NoE ACCENT AT2 (remote
sensing) and Aerosols SSC’s, Associate Editor of JGR-Atmospheres.
Le e u w
Truls Johannessen
Truls Johannessen works as a scientist for a research group in chemical oceanography
at the Geophysical Institute, University of Bergen where he received an MSc and PhD in
Marine Geology. As part of the SOLAS SSC, Truls is also the co-Chair of the
SOLAS/IMBER carbon group, the Chair of the SOLAS implementation group on carbon
and a member of the IOCCP committee. These responsibilities follow a devout career
within the SOLAS field, as a Chair for the Norweigen SOLAS initiative, and the position
of the Chair of the National Committee for JGOFS, NGOFS. His current research
revolves around the assessment of marine carbon sources and sinks; the effects of
North Atlantic Climate Variability and carbon flux and feedback within the Barents Sea
ecosystem; and the Ocean Abyssal Carbon Experiment.
Tr u l s J
o
h a n ne
s se n
Christiane Lancelot
Ch
e L an
r is t i an
ce lo t
Christiane Lancelot was born and raised in Brussels. She studied biochemistry at the ‘Université
Libre de Bruxelles (ULB)’ where she then completed her PhD on North Sea Phytoplankton Ecology.
She now holds the position of Professor and Director of the Laboratory ‘Ecologie des Systèmes
Aquatiques’ at ULB. Her research activity addresses the study and modelling of the response of
marine ecosystems to climate and anthropogenic changes throughout the understanding of the
interactions between plankton organisms and marine biogeochemical cycles (C, N, P, Si, Fe). Her
research questions the contribution of biological processes to air-ice-sea exchanges of CO2 and
DMS in the Southern Ocean as well as the response of coastal eutrophication and harmful algal
blooms (e.g. Phaeocystis) to changing nutrient loads and climate in the North Sea. In this scope,
she has been involved in several national and international projects and chaired and co-chaired
international conferences such as the Gordon Research Conference on Polar Marine Science.
Peter Liss
Peter Liss received his BSc in chemistry and physics from Durham University and his PhD in
marine chemistry from the University of Wales. After holding a NERC Fellowship at
Southampton University, he was appointed to the faculty of School of Environmental
Sciences at the University of East Anglia. His research has involved studies of biological
and photochemical processes of oceanic gases and their transfer mechanisms and rates
across the air-sea interface, as well as the roles that they play on atmospheric chemistry
and global climate regulation. He is Guest Professor at the Ocean University of Qingdao,
China; the recipient of the Challenger Society, the John Jeyes and the Plymouth Marine
Sciences Medal; and was awarded the title of ‘Royal Society of Chemistry’s Environmental
Chemistry Distinguished Lecturer’. He has served NERC for 5 years and was Chair of the
Scientific Committee of the IGBP. In 2007, he will take up the Chair of the Royal Society’s
Global Environmental Research Committee. He is currently Chair of the SOLAS SSC.
//12
Pe te r L
i
ss
Wade McGillis
is
McG i l l
Wade
Wade McGillis is currently Doherty Scientist at the Lamont-Doherty Earth Observatory
and Associate Professor of Earth and Environmental Engineering at Columbia University.
Dedicated to interdisciplinary environmental science and engineering; his research focuses
on understanding surface processes and the coupling between aqueous and atmospheric
systems, in particular, the role of air-sea CO2 exchange on local and global carbon cycles.
He was previously an Associate Scientist in the Applied Ocean Physics and Engineering
Department at Woods Hole Oceanographic Institution. He holds a BSc in mechanical
engineering from Northeastern University, and an MSc and PhD in mechanical engineering
from the University of California, Berkeley. He is currently Chair of the United States
Surface Ocean-Lower Atmosphere Study; a member of the World Climate Research
Program – Working Group on Fluxes; the Geochemistry Division at Lamont Doherty
Earth Observatory, and Associate Editor of the Journal of Geophysical Research.
Guang-Yu Shi
Guang-Yu Shi, a professor of the Institute of Atmospheric Physics, Chinese Academy
of Sciences. He was born in the Shandong province of China in October, 1942 and
graduated from the Department of Physics, Shandong University, in 1968. Dr. Shi got
his PhD degree in Atmospheric Physics from Tohoku University of Japan in Febuary
1982. His research background and interests are of the physical and chemical
processes of the Earth’s climate system, especially the atmospheric radiative transfer,
radiative forcing of climate change and the climate-chemistry interaction. For the
SOLAS Program, Dr. Shi has a special interest in the Asian Dust and Ocean EcoSystem
(ADOES) after he engaged in the Sino-Japanese ADEC (Aeolian Dust Experiment on
Climate Impact) Project during the past five years as the PI from Chinese side.
G ua ng
-Yu Sh
i
Shigenobu Takeda
Dr. Shigenobu Takeda is an associate professor of Aquatic Biology and Environmental
Science Laboratory at The University of Tokyo in Japan. His research interests include
biological and chemical interaction between trace metals such as iron and marine
phytoplankton, biogeochemical cycle of silicon and processes regulating primary
productivity in the ocean. He is taking an active part in North Pacific Marine Science
Organization (PICES) as a Chair of the Advisory Panel on Iron Fertilization Experiment.
ob u
Sh ig e n
Ta k e d a
Osvaldo Ulloa
Osvaldo Ulloa received his BSc in Marine Biology from the University of Concepción, Chile,
and his MSc in Marine Biology and PhD in Oceanography from Dalhousie University,
Canada. His PhD work concentrated on primary production and bio-optics. Osvaldo did
postdoctoral work on the carbon cycle at the Niels Bohr Institute in Copenhagen. He is
the Director of the Laboratory for Oceanographic Processes and Climate and a Professor of
Oceanography at the Universidad de Concepción. His research activities include
phytoplankton ecology; bio-optics and remote sensing of ocean colour; microbial
oceanography; interactions between biological and physical processes; and biogeochemical
cycling and climate. He has served as a member of the International Ocean Colour
Coordinating Group and of the Coastal Panel of the Global Ocean Observing System. He
currently is a member of the SCOR Working Group on Natural and Human-Induced
Hypoxia and Consequences for Coastal Areas
Os v a ld
o
Ul lo a
//13
partner projects
Dr. Hema Naik is a scientist at NIO. Her primary research
interest is biogeochemical cycling of nitrogen in the oceanic
oxygen minimum zones.
GLOBEC-CLIOTOP symposium
A major symposium organised by the
GLOBEC regional programme, CLimate
Impacts on Oceanic TOP predators
(CLIOTOP) has recently been announced.
The symposium will consist of sessions
from the four CLIOTOP working groups
plus cross-cutting sessions on climate
change and top predators; meso-scale
issues; global change implications for
management and conservation strategies
of top predators; and future scientific
challenges. The symposium will be held
3-7 December 2007 in La Paz, Mexico.
Further details: www.globec.org
GLOBEC is also holding a workshop on the
“impact of climate variability on marine
ecosystems: a comparative approach”.
The aim of the workshop is to enhance
understanding of the response of marine
ecosystems to environmental change and
to improve our knowledge of the impact of
climate variability on marine ecosystems.
The workshop will follow the Dahlem
conference format and will be devoted
entirely to discussion, with background
papers submitted prior to the workshop.
These papers, plus summaries of the
discussions, will be published in a special
volume of the ‘Journal of Marine Systems’.
If you would like to be kept informed of
the outcome of the meeting please contact
the GLOBEC IPO: globec@pml.ac.uk
On 4-5 September, a joint meeting of the
WCRP Working Group on Surface Fluxes
(WGSF; Chris Fairall, Chair) and the SOLAS
Focus 2 Implementation Group (IMP2;
Wade McGillis, Chair) met at the University
of Heidelberg in Germany. These closely
affiliated groups got together to discuss
coordination and collaboration, along with
planning future directions for the projects
prior to participation in the International
Workshop on Transport at the Air-Sea
Interface. In particular, WGSF
participated in the October 2006
WCRP Working Group on Numerical
Experimentation (WGNE) Surface Flux
Analysis Project (SURFA) in Boulder
Colorado. WGSF will provide a plan to
create a SURFA archive, including a list of
in situ platforms; a list of numerical
weather prediction products; a prospective
site for the archive; and a list of interested
researchers. WGSF has also most
recently developed a Handbook of
Climate Quality Measurements at Sea
and are in the process of completing
two review papers on air-sea gas and
particle fluxes. Other WGSF/IMP2
discussions were conducted on current
field campaigns, including a proposed
Southern Ocean GasEx cruise, the UK-led
DOGEE cruise, laboratory work, and
advances in remote sensing of gas transfer.
//14
The western continental shelf of India: A hotspot of
anaerobic biogeochemical transformations including
production of nitrous oxide
Hema Naik and S.W.A. Naqvi - National Institute of Oceanography, Goa. India. Contact: hema@nio.org
Oceanic oxygen-deficient zones (ODZs) are sites of
N2 production through heterotrophic
denitrification and autrotrophic anaerobic
ammonium oxidation. Such production of
N2 makes up for N2 fixation, thereby keeping
atmospheric N2 content constant over geological
time scales. However, an imbalance between the
two terms can bring about sizable changes in the
combined nitrogen inventory and affect oceanic
capacity to sequester atmospheric CO2, thereby
modulating climatic (glacial-interglacial)
cycles (Altabet et al., 2002; Codispoti, 2006).
Moreover, ODZs are also important for the global
N2O budget with the oceanic efflux accounting
for about one-third of all N2O inputs to the
atmosphere (Bange, 2006). N2O emission does
not occur uniformly over the oceanic surface,
though. In fact, the surface seawater is nearly
saturated with N2O in most areas, and substantial
supersaturations are only observed in upwelling
zones especially those containing ODZs. This is
because N2O is formed both during nitrification
and denitrification. Production via both pathways
is very sensitive to oxygen distribution in the low
range. N2O yield during nitrification increases
greatly at low oxygen levels. N2O is both
produced and consumed during denitrification
(NO3------> NO2 -----> NO -----> N2O -----> N2). In
most denitrifying environments, characterized by
the accumulation of nitrite, N2O concentrations
are generally quite low (<10 nM), but its
accumulation invariably occurs at the boundaries
of the ODZs making them strong net sources of
N2O to the rest of the ocean and ultimately to the
atmosphere (Codispoti & Christensen, 1985).
ODZs are located along the eastern boundaries
of the oceans with the exception of the Indian
Ocean where the ODZ is found in the northwest
– in the Arabian Sea - and it impinges upon a
much larger area of the continental margin than
do the ODZs of other oceans. The major portion
of the Arabian Sea ODZ lies beyond the
continental shelves in the northeastern and
central regions. Vertical profiles of N2O here
contain two maxima sandwiching a minimum,
and since the upper N2O maximum is located
barely a few tens of metres beneath the sea
surface it sustains large efflux of N2O to the
atmosphere. In addition to the perennial openocean ODZ, reducing conditions also develop
seasonally over the western continental shelf of
India (Naqvi et al. 2000). Although the largest of
its kind in the world (area ~200,000 km2), the
coastal ODZ still occupies a two orders of
magnitude smaller volume than its perennial
open-ocean counterpart. During the summer
monsoon, coastal circulation is conducive for
upwelling off the Indian west coast, which brings
low-oxygen water over the shelf. But this water is
generally prevented from surfacing due to the
presence of a thin (<10 m) warm, fresher layer
formed as a result of intense rainfall. Respiration
of organic matter coupled with strong nearsurface stratification leads to suboxia/anoxia at
very shallow depth (sometimes within 10 m) of
the sea surface. Off Goa, where sustained
observations have been made since 1997 at a
time-series station (depth ~ 28 m) CATS
(Candolim Time Series), near-bottom oxygen
reaches suboxic levels in August, and complete
denitrification is followed by sulphate reduction
in September-October (Figure). With the reversal
of surface currents, oxic conditions are reestablished in November-December. While the
oxygen deficiency over the Indian shelf has been
known to occur for several decades, there is no
indication of sulphate reduction in the historical
data sets. Therefore, it would seem that the
intensification of the oxygen-deficient conditions
has occurred in recent years, possibly as a
consequence of increased loading of nutrients
from land (Naqvi et al., 2000).
The most unexpected aspect of N2O distribution
is the unprecedented accumulation of N2O
observed during the late summer – early
autumn in the inner- and mid- shelf regions
north of 12ºN. The highest concentration (765
nM) observed is about four times the highest
values reported from the eastern tropical South
Pacific. The N2O build-up coincides with the
accumulation of nitrite and depletion of nitrate,
the telltale signs of denitrification. This is in
sharp contrast to the above-mentioned trend in
the open ocean ODZ. These observations
strongly point to transient production of N2O
from nitrate through a reductive pathway.
Even when a net consumption of N2O occurs
in near-bottom waters, surface concentrations
(5-436 nM, mean 37.3 nM) during the
upwelling period are almost always far in
excess of the corresponding saturation values.
Employing available models of air-sea gas
exchange, the average N2O flux to the
atmosphere has been computed to range from
39 to 264 µmole.m-2.d-1. An extrapolation of this
flux, over a period of six months, yields a total
N2O efflux of 0.05-0.38 Tg N2O from the study
region (Naqvi et al. 2006). This is roughly of the
same magnitude as the most recent estimate of
N2O efflux (0.39 Tg N2O y-1) from the entire
Arabian Sea (Bange et al., 2001). If some of
the high efflux is due to above-mentioned
intensification of the coastal ODZ, it would
imply that human activities may lead to an
enhancement of N2O emission from the ocean.
References
Altabet, M.A., et al. (2002), Nature, 415, 159-162.
Bange, H.W. (2006), Atmos. Environ., 40, 198-199.
Bange, H.W., et al. (2001), Atmos. Chem.
Phys., 1, 61-71.
Codispoti, L.A. (2006), Biogeosci. Discuss., 3,
1203-1246.
Codispoti, L.A. & J.P. Christensen (1985), Mar.
Chem., 16, 277-300.
Naqvi, S.W.A., et al. (2000), Nature, 408, 346-349.
Naqvi, S.W.A., et al. (2006). In: Past and Present
Water Column Anoxia, L.N. Neretin, editor,
Springer, pp. 195-224.
Figure:
Monthly-/fortnightly-averaged
records showing annual
cycle of (a) temperature,
(b) salinity, (c) O2, (d-g)
inorganic nitrogen species,
and (h) hydrogen sulphide
at the Candolim Time Series
(CATS) site (15°31’N, 73°39’E)
based on observations from
1997 to 2004 (from Naqvi
et al., 2006).
partner projects
GREENCYCLES is a Marie Curie
Research Training Network (RTN),
funded by the European Commission’s
Sixth Framework Programme. Like all
RTNs, GREENCYCLES has both scientific
and training aims. Its overall scientific
aim is to reduce uncertainties associated
with biogenic feedbacks on climate and
ecosystems. Its training aim is to
support the development of young
scientists interested in a research career
in global biogeochemical cycles. To this
end, 17 researchers are being hired
across the 11 labs in the network.
GREENCYCLES researchers are working
on marine-related projects at LSCE (Gifsur-Yvette, France), UEA (Norwich, UK),
and MPI-BGC (Jena, Germany).
Maciej Telszewski, originally from
Poland (it is necessary for RTN
researchers to move country to
undertake their research), is a
GREENCYCLES researcher based at UEA.
Maciej is developing novel techniques
to reconstruct atmosphere-ocean
surface CO2 fluxes from satellite
measurements, in order to better
constrain ocean carbon general
circulation models. Meike Vogt, also at
UEA but originally from Germany, is
working on the development of DMSP
and DMS parameterisations for the
Dynamic Green Ocean Model (DGOM)
SOLAS Special Report: Chinese Information Center for Global Environmental Change Studies
In China, the research groups that focus on the global
change issues were greatly increased since the end of
last century. The information demands of the
international global change research and co-operation
were raised. In 1999, a professional institute for global
change information service, named the Chinese
Information Center for Global Environmental Change
Studies (CICGECS), was established in Lanzhou City,
northwestern China. CICGECS is sponsored by the
Scientific Information Center for Resources and
Environment of Chinese Academy of Sciences (CAS),
also named Lanzhou Library of National Scientific
Library, and Chinese National Committees for IGBP,
IHDP and WCRP. Some other important related
organizations, for example, are the Chinese National
Committee for DIVERSITAS, the Institute of Geographic
Sciences and the Natural Resources Research of CAS,
who have given CICGECS some special supports.
The focus of CICGECS is to:
• Serve the researchers on global change studies with
data, documents and information;
• Enhance information exchange and academic
intercommunions between Chinese and international
organizations and researchers;
• Maintain and build databases and information
systems related to global change studies;
• Vacate time for information analysis and soft science
research on global change.
• CICGECS has been one of the important information
service institutes in China. It is playing indispensability
roles in the fields of global change studies.
Website: www.globalchange.ac.cn
UEA is hosting British researcher,
Nicholas Stephens, and MPI-BGC is
hosting Italian researcher, Valentina
Sicardi. Nick is also working on the
DGOM, but concentrating on the
implementation of a nitrogen cycle,
including the role of nitrogen fixers.
In contrast, Valentina, originally from
Italy, will be using an atmospheric
tracer transport model in various
modes to quantify oceanic carbon
processes and detect changes in the
general ocean circulation.
GREENCYCLES sponsors the integration
of these projects across interested
European labs, and especially with the
development of earth system models.
GREENCYCLES also sponsors the
organisation of relevant workshops
and meetings, and the attendance of
GREENCYCLES researchers and senior
scientists at training events such as the
SOLAS summer school.
For more information on these and
other GREENCYCLES projects please
go to www.greencycles.org
E-mail: gcinfo@lzb.ac.cn
Director: Prof. Zhang Zhiqiang (zhangzq@lzb.ac.cn)
Executive Secretary: Dr. Qu Jiansheng (jsqu@lzb.ac.cn)
//15
partner projects
The International
Association for
Meteorology and
Atmospheric Sciences
(IAMAS) is one of 7
associations of the
International Union
of Geodesy and
Geophysics (IUGG).
IAMAS organizes international
scientific assemblies every two years.
In the years coinciding with IUGG
general assemblies, IAMAS joins other
associations in organizing a wide range
of scientific sessions, many of which are
coordinated across associations.
The next of these scientific assemblies
will be held in Perugia, under the
theme “Earth, Our Changing Planet”.
In between the quadrennial general
assemblies of the IUGG, IAMAS convenes
its own scientific assemblies, sometimes
jointly with other associations or
programmes. The last IAMAS scientific
assembly was held in Beijing from 2-11
August 2005. This assembly was
coordinated with the Open Scientific
Meeting of IGBP’s PAGES project.
With the IPY in mind, IAMAS will
be joining with the International
Association for the Physical Sciences of
the Oceans (IAPSO) to organize a joint
scientific assembly in Montreal, Canada
from 20-29 July 2009.
The scientific efforts of IAMAS are
carried out by its ten international
commissions: Atmospheric Chemistry
and Global Pollution (ICACGP);
Atmospheric Electricity (ICAE); Climate
(ICCL); Clouds and Precipitation (ICCP);
Dynamical Meteorology (ICDM); Middle
Atmosphere (ICMA); Ozone (IOC);
Planetary Atmospheres and their
Evolution (ICPAE); Polar Meteorology
(ICPM); and Radiation (IRC).
Finally, IAMAS also undertakes a number
of efforts to help build bridges within
the international scientific community
intended to help foster cooperation and
capacity-building. These efforts include
a biannual newsletter, appointing
scientists as liaisons to international
programmes and coordinating bodies
(e.g., WMO, WCRP, SCOR, etc.), and,
to the extent possible, providing travel
assistance to international meetings for
young scientists and scientists from
nations in need.
IAMAS (http://www.iamas.org/)
IUGG (http://www.iugg.org/)
IAPSO (http://www.olympus.net/IAPSO/)
Perugia, Italy, 2007
(http://www.IUGG2007Perugia.it/).
Andreas Albertino Hutahaean graduated from the University of Bremen in
2002 and works as a researcher at the Research Center for Maritime and
Non Living Resources, Agency for Marine and Fisheries Research (BRKP) in
Jakarta, Indonesia. At the moment his research focuses on the dynamics
of nutrients and water cycles in the Indonesian Trough Flow System
particularly in the Lombok Strait, Indonesia. This research also linked to
the interactions among land, sea surface and atmosphere in the location.
The dynamic of nutrients and water cycles
in Lombok Strait, Indonesia
Andreas A. Hutahaean1, Selvi Makarim1, Agus Supagat1,2, Sugiarta Wirasantosa1
Research Center for Maritime and Non Living Resources, Agency for Marine and Fisheries Research (BRKP), Jakarta,
Indonesia.; 2Dept. of Oceanography, Bandung Institute of Technology, Indonesia. Contact: andreas@dkp.go.id
1
The Indonesian Through Flow is the leakage
of western tropical Pacific water into the
southeastern tropical Indian Ocean through
the Indonesia seas. This movement of water
is an important pathway for transfer of
climate signals and their anomalies around the
world’s ocean. While the heat and fresh water
carried by this flow are known to effect the
basin budget of both the Pacific and Indian
Oceans, the magnitude and vertical
distribution of the Indonesian Through Flow
are not well known. The thousands of islands
and numerous passages that connect a series
of large, deep basins within the Indonesian
seas provide for the flow (Figure 1) . The
tendency for ocean boundary currents to pass
through the westward-most available passage
and the sill depths of the various passages,
largely define this pathway. The Indonesian
Through Flow exits into the Indian Ocean
through the major passages along the lesser
Sunda Island chain one of which is the
Lombok strait (Gordon and Fine, 1996).
The Lombok Strait separates the Indonesian
islands of Bali and is one of the most important
zones through which water is exchanged
between the Pacific Ocean and the Indian
Ocean and plays an important role in the
global ocean circulation. Transport through the
Strait exhibits large seasonal variations due to
changes in the atmospheric pressure gradient
between the Pacific and the Indian Ocean
which is a function of the monsoon. As a
result, the seasonal currents through the strait
are bidirectional. The main topography features
inside the Lombok Strait are an island (Nusa
Penida) and a sill between this island and the
smaller Lombok islands in the southern mouth
of the strait. The current pattern consists of the
superposition of the main flow and the tidal
flow. In the upper 100 meters the current
velocity reaches 1.5 m/s at the center of the
strait and 3.0 m/s in the sill region (Gordon, et
al., 2003; Spritall, et al., 2004)
This research emphasizes mechanisms
and feedbacks that control the dynamic
nutrient and water cycles in the Lombok Strait
as one of the exit gates of Indonesian Through
Flows in the frame work of global climate
change phenomena by measuring variables
such as chemical parameters (nutrient, BOD,
COD, etc), biological parameters (chlorophyll-a)
and physical parameters (current velocity,
salinity, temperatures, wind speed and
direction, etc) regularly. One set of
observations is shown on Figure 2, on the
comparison of Phosphate, Silicate, Nitrite
and Nitrate between St-3 and St-6.
References
Gordon,A. L. and R.A. Fine. 1996. Pathways of
water between the Pasific and Indian oceans in
The Indonesia seas. Nature. 379. 146-149.
Gordon, A.L., R. D. Susanto, and K.
Vranes. 2003. Cool Indonesian
Troughflow as a consequence of
restricted surface layer flow. Nature.
425. 824-828.
Spritall, J., S. Wijffels, A. L. Gordon,
A. Frield, R. Dwi Susanto, I. Soesilo,
J. Sopaheluwakan, Y. Surachman,
and H. M. van Aken. 2004.
INSTANT: A new international array
to measure the Indonesian
troughflow. EOS. 85, N0. 39.
Figure 1: Maps of some sampling
locations in the Lombok strait.
//16
partner projects
The International
Commission on
Climate (ICCL), a
constituent
commission of the
International
Association of
Meteorology and
Atmospheric Sciences (IAMAS), itself a
constituent Association of the International
Union of Geodesy and Geophysics (IUGG),
was established in 1977 in response to the
increasing research activity into the
physical basis of climate and its variability.
A very important role of the ICCL is to
encourage, facilitate and promote climate
research activities through ICCL
sponsored/co-sponsored sessions at
biennial (quadrennial) IAMAS (IUGG)
conferences. The ICCL and IAMAS are
working actively and collaboratively with
the International Association for the
Physical Sciences of the Ocean (IAPSO) of
IUGG to promote and facilitate stimulating
conference sessions for the
presentation/discussion of climate research
activities associated with the air-sea
interface. The upcoming XXIV General
Assembly of IUGG in Perugia, Italy (2-13
July 2007) [www.iugg2007perugia.it/] will
be an excellent forum to present such
research activities. ICCL welcome and
encourage online abstract submissions
from members of the SOLAS community
for IUGG 2007.
ICCL http://www.iccl-iamas.org/
iLEAPSupcoming events
Figure 2: Comparison of Phosphate, Silicate, Nitrite and Nitrate between St-3 and St-6 in Lombok Strait.
SOLAS Special Report: China SOLAS Special Session
China SOLAS Special Session held at the Western Pacific
Geophysics Meeting, Beijing, China, July 24-27, 2006
The China SOLAS special session on Asian Dust and the
Ocean Ecosystems (ADOES) had a wide range of relative
topics that covered many aspects of ADOES.
The progress of the China SOLAS project since established
in 2002 was summarized, especially in recent years (Gao).
The first phase of China SOLAS was supported by the
National Natural Science Foundation of China (NSFC) with
a budget of 8 Million RMB for 2004-2008. The project has
finished a cruise in the Yellow Sea and the South China
Sea in 2005 and conducted another in the Yellow Sea in
2006. They also plan to make a suggestion to initiate an
international task team: ADOES, which will mainly involve
researchers in China, Japan, and Korea, as well as
researchers from SOLAS countries beyond Asia. They are
planning a few meetings to promote the second phase of
China SOLAS project. Many of the talks were related to
measurements and analyses of Asian dust. Remote sensing
of dust storms are investigated using satellite thermal
infrared measurements (Zhang). Heterogeneous chemical
reactions of SO2 and NO2 at the surface of mineral dust
particles and on the Reactive halogen compounds (RHCs)
are presented (Zhu and Ge), as well as, the new
observations of atmospheric nitrogen deposition and
aerosol over the Yellow Sea and the South China Sea
(Qi and Guo). Their compositions were also analyzed.
Important biogeochemical variables were measured over
the northern South China Sea, the southern Yellow Sea
and the coastal waters of East China Sea (Yin and Zhai).
The variables include nutrients, Chl a, bacteria, dissolved
CO2 and oxygen. Spatial distributions of these were
investigated. In order to observe CO2 changes a new
sensor, an in-situ optical fibre chemical sensor, was
developed and applied in the field measurements (Lu).
The correlations between Asian dust events and biological
productivity in the western North Pacific Ocean were
addressed and a model was used to understand the
impacts of iron supply on phytoplankton community
structure in the North Pacific Ocean (Yuan and Jin).
The dependence of depth of oceanic mixed layer on bulk
aerodynamic algorithm, breaking waves, and Langmuir
circulation were studied using a model (Zhao). The
distribution of Mercury in Mangrove Ecosystem of
Zhangjiang Estuary was investigated (Ding).
Chairs: X. Jin, H. Gao and T. Zhu
The official launch
of iLEAPS-China is
in connection with
the ESSP Open
Science Conference in Beijing, November
9-12, where the iLEAPS Science Plan and
Implementation Strategy will be available
in Chinese. iLEAPS is co-sponsoring
sessions at the AGU Fall Meeting, 11–15
December in San Francisco: Aerosol
Cloud-Precipitation Interaction: Facts and
Fiction (Session A08), Land-Atmosphere
Interactions and the Hydrological Cycle in
the Monsoon Asia Region (Session B22).
iLEAPS recognized project, ‘Northern
Eurasia Earth Science Partnership
Initiative’, NEESPI, is organizing a session
on: Integrated Approach to Regional
Climate and Environment Change Studies
(GC08). Journal special issues from the
iLEAPS Boulder events in January, the
Science Conference and Specialist
Workshop on Flux Measurements in
Difficult Conditions, will be published in
Tellus B and Ecological Applications,
respectively. Bookmark the iLEAPS web
site (http://www.atm.helsinki.fi/ileaps) for
upcoming information on 2007 events,
for example the European Commission
Marie Curie-iLEAPS events; sessions at
IUGG General Assembly in July; and
workshop on Aerosol-Cloud-PrecipitationClimate interactions.
//17
partner projects
The oceans absorb one third of the
anthropogenic carbon emitted to the
atmosphere each year. Scientists are
using surface underway observations of
pCO2 to determine the pattern, controls,
and interannual variability of air-sea CO2
exchange. A workshop that will bring
together the international community to
discuss and interpret surface pCO2 data,
and to find synergies with other carbonrelated observations (repeat hydrographic
sections, time series, and remote
sensing), will be held in mid-April 2007
at UNESCO headquarters in Paris.
State-of-the-art modeling and data
assimilation techniques will be presented,
along with strategies to determine the
shape of a future observing network.
A meeting on the vulnerability of the ocean
uptake to climate change will be held in
conjunction with the surface carbon
workshop. This meeting will focus on
predictions of the behaviour of the ocean
sink of carbon into the future and will
examine how climate change could impact
ocean temperature, circulation and
structure and how these changes may
affect marine ecosystems and the ocean’s
ability to absorb CO2 from the atmosphere
Visit the IOCCP website: www.ioccp.org
Monsoon Asia
Integrated Regional
Study is a new
international research
program of the Earth
System Science
Partnership and was established by
START to address key questions about
the coupled human and environment
system in the monsoon Asia region.
MAIRS, guided by a Scientific Steering
Group (SSG), is supported by an
International Project Office (IPO), and is
looking to partner with other projects for
research and other activities.
MAIRS began by organizing workshops,
by selection of members for the SSG,
and by opening the IPO in Beijing in
2005, and this office is supported by
the Chinese Academy of Science.
Marc Strous teaches Microbial Ecology and supervises
anammox research at the Radboud University Nijmegen.
Originally a chemical engineer, he completed his PhD in
Microbiology in 2000 at the Delft University of Technology.
During his PhD, he identified the first anammox bacterium.
He has been a part of anammox research since.
Anaerobic ammonium oxidation:
from mystery guest to global player
Marc Strous and Mike S. M. Jetten
Department of Microbiology, Radboud University Nijmegen, Netherlands. Contact: m.strous@science.ru.nl
Anaerobic ammonium oxidation (anammox) is the
Nitrogen’s cycle new kid on the block. For a long
time the Nitrogen cycle was considered to be
complete, and defined by two paradigms. First,
“ammonium is inert in the absence of oxygen”.
Second, “Denitrification is the only sink for fixed
nitrogen in the oceans”. With the discovery of
anammox both are no longer true, because
anammox combines nitrate and ammonium into
dinitrogen gas in the complete absence of oxygen.
The responsible bacteria conserve the energy from
the above reaction to fix carbon dioxide and grow.
Or do they really grow? These bacteria divide only
once every two weeks at maximum speed, far
slower that all other known N-cycle bacteria.
Surprisingly, several recent studies have shown
that these unhurried creatures may actually
constitute a major sink for fixed nitrogen in
the oceans (Thamdrup and Dalsgaard, 2002;
Kuypers et al, 2003; Kuypers et al, 2005).
In the 1980’s, 1990’s, oceanographers were still
generally unaware of “anammox”. The oceanic
N-losses were still by definition caused by
denitrification and were measured by a method
known as acetylene inhibition which does not
detect N-losses caused by anammox. In the
meantime, a group of wastewater engineers at
Delft University of Technology silently invested
two decades to build a laboratory bioreactor
based on anammox – for the cheap removal of
ammonia from wastewater. Ultimately they
were successful and the key was the
engineering of a system that allowed for the
very slow growth of the anammox bacteria.
Once the anammox bacteria grew, it also
became possible to develop the tools to
detect the presence and activity of these
bacteria in Nature. So far this has been done
for anoxic basins, sediments and upwelling
regions. It turned out anammox bacteria were
active everywhere and even contributed
between 50 and 100% to N-losses in many
cases. Currently, many research groups have
joined the effort to assess the contribution of
anammox to marine N-losses on a global
scale. Interestingly, the consequences of the
rewiring of the nitrogen cycle for the marine
carbon cycle are still completely unexplored.
See also: www.anammox.com
References
Thamdrup B. & Dalsgaard T. (2002)
Production of N2 through Anaerobic
Ammonium Oxidation Coupled to Nitrate
Reduction in Marine Sediments.
Appl.Environ.Microbiol. 68: 1312-1318
Kuypers M.M.M., Sliekers A.O., Lavik G., Schmid
M., Jorgensen B.B, Kuenen J.G., Sinninghe
Damste J.S., Strous M., Jetten M.S.M. (2003)
Anaerobic ammonium oxidation by anammox
bacteria in the Black Sea. Nature 422: 608-611.
Kuypers M.M.M., Lavik G., Woebken D.,
Schmid M., Fuchs BM., Amann R., Jorgensen
B.B., Jetten M.S.M. (2005) Massive nitrogen
loss from the Benguela upwelling system
through anaerobic ammonium oxidation PNAS
USA 102 (18): 6478-6483.
In January, a meeting of 10 experts was
held on the Initial Science Plan (ISP) of
MAIRS. The main outcome was the
identification of four crucial zones in Asia:
Coastal, Mountain, Semi-Arid and Urban
Zones. In April, a workshop with 20
scientists from across Asia provided further
substance, and the ISP has been completed.
Frits Penning de Vries, Executive
Director IPO, Beijing
(fritspdv@mairs-essp.org)
http://www.mairs-essp.org
//18
Sandy Thomalla is a PhD student at the University of Cape Town, South Africa. In
2003 she received a British Commonwealth split-site bursary which allowed her to
base her PhD studies at the National Oceanography Centre, Southampton where
her work has been affiliated with the George Deacon Division and the Atlantic
Meridional Transect programme. She is currently completing her dissertation on the
export of carbon in the North and South Atlantic Ocean.
Particulate organic carbon export from the North and South Atlantic gyres:
the 234Th/238U disequilibrium approach
Sandy Thomalla1, Robert Turnewitsch2, Mike Lucas2, Alex Poulton2
1Department
of Oceanography, University of Cape Town, South Africa; 2National Oceanography Centre, Southampton, UK. Contact:
The central subtropical gyres of the open
oceans have long been regarded as
homogenous and static “marine deserts”
with low rates of primary production (Karl
et al., 1996). However more recent studies
have shown a large degree of variability in
phytoplankton productivity which coupled
with the immense size of the subtropical
gyres (> 40% of the Earth’s surface) makes
the overall carbon export of these areas
significant (up to 50% of global carbon
export) (Teira et al., 2005). Quantifying and
better constraining the role of the North
and South Atlantic in the global carbon
budget is addressed as part of the Atlantic
Meridional Transect (AMT) programme
(http://www.amt-uk.org). During AMT 14,
we used the radioactive disequilibrium
between naturally occurring particlereactive 234Th (t1/2 = 24.1 d) and its
conservative (soluble) parent 238U (t1/2 =
4.47 x 109 yr) to quantify particulate
organic carbon (POC) export from the
surface waters of the Atlantic Ocean
between ~ 50ºS and ~ 50ºN during
Figure 1: A composite SeaWiFS image of surface
chlorophyll for the Atlantic showing the AMT 14
cruise track. Locations of thorium CTDs are marked
in bold.and labelled.
April/May 2004. The estimated downward
flux of 234Th is combined with measured
ratios of POC/234Th on large settling
particles to quantify POC export (Buesseler
et al., 1992).
upwelling regions can be substantial, and
that spatio-temporal variability in these
areas of the world’s oceans needs to be
considered more fully in the context of
global oceanic carbon export.
Based on latitudinal distributions of selected
hydrographic and biological parameters the
transect was divided into six regions:
‘temperate’ (35º - 50ºN and 35º-50ºS),
‘oligotrophic’ (20º-35ºN and 5º-35ºS),
‘equatorial’ (5ºS- 5ºN) and ‘upwelling’ (5º20ºN). The lowest POC export fluxes were
found in the oligotrophic gyres and ranged
from 0 in the northern to 6 mmol C m-2d1 in the southern oligotrophic indicating a
tightly coupled food web. Enhanced POC
export was associated with the equatorial
(25 mmol C m-2d-1) and upwelling region
north of the equator (15 mmol C m-2d-1).
POC export in the temperate regions ranged
from 7 mmol C m-2d-1 to a maximum of
41 mmol C m-2d-1. High fluxes at the
poleward edges of the gyres probably result
from episodic nutrient loading processes
associated with submesoscale features.
Results from this study suggest that
although carbon export in the oligotrophic
centres of the gyres may be low, carbon
sequestration in the temperate fringes of
the gyres as well as in the equatorial and
References
Karl, D.M., Christian, J.R., Dore, J.E., Hebel,
D.V., Letelier, R.M., Tupas, L.M., Winn,
C.D., 1996. Seasonal and interannual
variability in primary production and particle
flux at Station ALOHA. Deep-Sea Research
II 43(2-3), 539-568.
Teira, E., Mouriño, B., Marañón, E., Pérez,
V., Pazó, M.J., Serret, P., de Armas, D.,
Escánez, J., Woodward, E.M. Fernández, E.,
2005. Variability of chlorophyll and primary
production in the Eastern North Atlantic
Subtropical Gyre: potential factors affecting
phytoplankton activity. Deep-Sea Research I
52, 569-588.
Buesseler, K.O., Bacon, M.P., Cochran, J.K.,
Livingston, H.D., 1992. Carbon and
nitrogen export during the JGOFS North
Atlantic Bloom Experiment estimated from
234
Th:238U disequilibria. Deep-Sea Research I
39, 1115-1137.
Figure 2: Primary production estimates integrated to the 1% light level and POC fluxes along the AMT 14 transect.
CTD identifiers and biogeographical domains are indicated at the top of each diagram. (I) temperate; (II)
oligotrophic; (III) equatorial and (IV) upwelling.
//19
partner projects
SOLAS Special Reports
The 4th International Symposium on Biological
and Environmental Chemistry of Dimethyl
Sulphide (DMS), Dimethylsulponioproportionate
(DMSP) and related compouds.
PAGES (Past Global Changes) is the one
core project within the International
Geosphere-Biosphere Programme (IGBP)
that contributes to our understanding
of ongoing and future global change by
looking back at environmental changes
in Earth’s recent geological history. Past
changes have to be reconstructed
tediously from natural (sediments, trees,
ice, corals, cave deposits, etc.) and
documentary archives. However, they
justify this extra effort by revealing a
rich inventory of various states,
transitions, and modes of the Earth
system, most of which are beyond the
reach of modern observations.
Such past scenarios are used to
demonstrate and quantify the variability
of the Earth system and to infer
underlying mechanisms, to improve the
skill of models to simulate Earth system
states other than the present one, to
define envelopes of natural environmental
variability against which anthropogenic
impacts are assessed, and to provide case
studies for the interaction of humans with
the climate-environment system.
PAGES’ activities address and often
integrate across all components of the
past Earth system, including those most
relevant to SOLAS science. Changes in
the past ocean’s physical and
biogeochemical conditions are
addressed by the International Marine
Past Global Changes Study (IMAGES)
under the joint umbrella of PAGES and
SCOR. The changing composition of the
past atmosphere is most prominently
studied using ice cores, while past
atmospheric dynamics is also addressed
by other groups, including a new
working group to be launched at the
2007 EGU assembly, that will exploit
inferences from Aeolian deposits in the
ice, ocean, and on land.
Website: http://www.pages-igbp.org
Direct contact: Thorsten Kiefer
(kiefer@page.unibe.ch)
The 4th International Symposium on Biological and
Environmental Chemistry of DMS(P) was held at the
University of East Anglia in Norwich, UK from 2-6 May
2006 http://lgmacweb.env.uea.ac.uk/lgmac/dmsp/ . The
meeting was hosted by Dr. Gill Malin and colleagues from
the Laboratory for Global Marine and Atmospheric
Chemistry (LGMAC, http://lgmacweb.env.uea.ac.uk/lgmac/)
in the School of Environmental Sciences.
Sixty five people attended from various university and
institute laboratories in the UK, Canada, China, Germany,
India, Japan, Korea, The Netherlands, New Zealand,
Romania, Spain and Switzerland. Research on DMS in the
environmental context was stimulated by the publication
of the first seawater DMS concentration measurements by
James Lovelock in Nature in 1972 (Nature vol 237 page
452). So it was fantastic to have him attend the first day
of the symposium as our guest of honour. Jim invented
the electron capture detector and during his opening talk
‘Thoughts on DMS and related compounds’ he showed a
photograph of the very first ECD-GC that he used to
make those first DMS measurements.
Most SOLAS newsletter readers will be aware that a large
body of research has built up following Jim’s pioneering
publication. It is now well known that this sulphur trace gas
is produced in seawater mainly due to the activities of
marine microorganisms. The flux of DMS to the atmosphere
leads to the production of DMS oxidation products. The
resultant aerosol particles reflect the Sun’s energy back into
space directly and indirectly because of their ability to act as
cloud-seeding particles. In this way DMS makes a vital
contribution to the global biogeochemical sulphur cycle and
influences the Earth’s climate.
We had a great meeting with a wide range of talks and
posters and some lively discussion. The symposium covered
the full range of current DMS research. There were special
sessions on how oxidative stress & radiation affect DMS
emissions, on how DMS and related compounds act as
infochemicals and signalling compounds and the allimportant recent method developments. There were also
mixed sessions covering a host of other DMS-related research
topics including present and past climate modelling, microbial
ecology, advances using molecular techniques and reports on
field studies ranging from the Arctic and Antarctic to the
Mediterranean and tropical Atlantic.
There was also a full social programme including an
afternoon tea sponsored by the SOLAS International
Project Office with a welcome from the Lord Mayor of
Norwich. The organisers extend their thanks to SOLAS,
Agilent Technologies, Shimadzu UK Ltd., Varian Ltd.,
GlycoMar Ltd., The UK Challenger Society for Marine
Sciences, The Scientific Committee on Oceanic
Research, LGMAC, the School of Environmental
Sciences and the University of East Anglia Science
Faculty for their support of this meeting. We also thank
all who attended for making the meeting so enjoyable.
For those who were not able to join us more details,
including the downloadable programme and abstracts
book, can be found on the symposium website
http://lgmacweb.env.uea.ac.uk/lgmac/dmsp/. A special
issue of papers from the symposium will be published in a
special issue of the journal Aquatic Sciences Research
Across Boundaries in 2007. This next symposium will be in
about 3 years time, but the venue has yet to be decided.
Special Session on Asian Dust held at WPGM,
Beijing, China, July 24-27, 2006
A Special session on Asian dust and its impacts on climate
and biogeochemical cycles was held at the Western Pacific
Geophysical Meeting at Beijing, China, July 24-27, 2006.
The session aimed at exploring the current state of
knowledge of the Asian dust-atmosphere-oceanclimate interactions with a goal of facilitating more
interdisciplinary research efforts. Participants from
China, Japan, Indian and the United States joined this
session with results from observations, measurements,
and model simulations, addressing a variety of topics
relating to Asian dust. One of the active discussion
topics is dust-pollution interactions, in particular over
China and East Asia. Results from aircraft-based
surveys show that soot pollution represents a major
type of air pollution in China (W. Wang, China), and
the complicated mixing state of dust with
anthropogenic substances were clearly seen in SEM
images based on aircraft sampling during a major East
Asia dust storm (J. Anderson, USA). Several
presentations of model simulations demonstrated the
transport of Asian dust and pollution-derived
substances over East Asia and the North Pacific and
their effects on the surface radiation budget (M. Chin,
Y. Tang, USA). Radiative Forcing of Mineral Dust from
Sahara, Middle Asia, and East Asia was compared (A.
Zhu, USA). Impacts of dust storms on the regional air
quality in other regions of Asia, such as the IndoGangetic Basin in South Asia, were discussed as well
using ground and satellite data (A. K. Prasad, India).
Impacts of Asian dust and pollution may even reach far
distance as observed during the cruises from Shanghai,
China to the Antarctica (J. Wang, China). Another
active area of discussions is the impact of Asian dust on
the composition of the marine atmosphere and the Fe
distributions in surface water of the North Pacific.
Shipboard observations reveal substantial transport of
anthropogenic substances associated with dust from
East Asia to the subarctic North Pacific (M. Uematsu,
Japan). Input of Asian dust may affect the
concentrations of Fe in the surface water of the North
Pacific (E. Boyle, USA). Results of in-situ ironenrichment experiments (SEEDS and SEEDS II)
performed in the western subarctic Pacific in summer
2001 and 2004 were also discussed with new insights
(A. Tsuda, Y. Kondo, Japan). These discussions clearly
confirmed the important roles of Asian dust on
radiative forcing and ocean biogeochemical cycles, in
particular in the North Pacific Basin. With the
challenges in better quantifying the Asian dust-climatemarine ecosystem relationships, more interdisciplinary
research efforts should be encouraged through
internationally well coordinated programs such as
SOLAS and GEOTRACES.
Chairs: Yuan Gao, Zhisheng An, Huasheng Hong, and
Mitsuo Uematsu
Photo: DMS(P) Symposium participants (Photo: Sheila Davies).
solas news
To reduce costs and environmental
impact, The SOLAS Newsletter will
convert to online format for most
subscribers. To subscribe to the hardcopy,
please email e.breviere@uea.ac.uk and
include your full address
//20
Weiqing Zhang completed her PhD in 2002 in atmospheric science at Naning
University in China. She was a postdoctoral fellow at Bedford Institute of
Oceanography in Canada, where she is currently a research associate studying airsea fluxes and the influence of storms on air-sea gas exchange.
Impacts of winter storms on air-sea gas exchange
Weiqing Zhang1,2, Will Perrie1,2, and Svein Vagle3,4
1
Dept. Engineering Math, Dalhousie Univ., Halifax, Canada; 2Fisheries & Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Canada; 3Institute of
Ocean Sciences, Sidney, British Columbia, Canada; 4Dept. Earth and Ocean Sciences, Univ. Victoria, Victoria, Canada. - Contact: zhangw@mar.dfo-mpo.gc.ca
during the passage of the storm, and
uncertainties in the sea state and bubble
processes suggest the need for further study.
The objective of this study is to investigate airsea gas exchange during winter storms and
possible mediation by bubbles, using field
measurements from the C-SOLAS mooring at
Ocean Station Papa in the Northeast Pacific
(50°N, 145°W). We analyze a 6-day storm in
January 2004 with winds in excess of 15 ms-1
over a 2-day period, and show that increasing
gas transfer rates are coincident with
increasing winds and deepening depth of
bubble penetration. This process depends
closely on the peak of the storm, wind speed
and the composite sea state.
References
Our results are shown in Figure 1, suggesting
that the bubble enhancement to the gas
transfer velocity for O2 and N2 is up to
~20%, in comparison to the formulation by
Wanninkhof and McGillis (1999), and that
the latter formulation plus the bubble
formulation of Woolf (1997) can qualitatively
approach values achieved by the Zhao et al.
(2003) formulation. The simulated storms
also can exhibit asymmetry in the sense that
a sudden increase in gas fluxes and
concentrations may occur with the onset of a
storm, and follow by gradual recoveries to
pre-storm conditions. Thus, wave breaking
clearly influences the gas transfer velocity
Asher, W. E., L. M. Karle, B. J. Higgins, and P.
J. Farley (1996), The influence of bubble
plumes on air/seawater gas transfer velocities,
J. Geophys. Res., 101, 12027-12041.
Farmer, D. M., C. L. McNeil, and B. D.
Johnson (1993), Evidence for the
importance of bubbles in increasing air-sea
gas flux, Nature, 361, 620-623.
Perrie, W., W. Zhang, X. Ren, Z. Long, and J.
Hare (2004), The role of midlatitude storms
on air-sea exchange, Geophys. Res. Let, 31,
No. 9, L09306, doi: 1029/2003GL019212.
Wanninkhof, R., and W. M. McGillis (1999),
A Cubic relationship between gas transfer
and wind speed, Geophys. Res. Let., 26,
1889-1892.
Woolf, D. K. (1997), Bubbles and their role in
gas exchange, In The Sea Surface and Global
Change, eds. R. A. Duce and P. S. Liss, pp. 173205, Cambridge University Press, Cambridge.
Zhao, D., Y. Toba, Y. Suzuki, and S. Komori
(2003), Effect of wind waves on air-sea gas
transfer: Proposal of an overall CO2 transfer
velocity formula as a function of breakingwave parameter, Tellus, 55B, 478-487.
Gas transfer velocity (cm / h)
U10(ms-1) & W(%)
The bubble-mediated gas transfer velocity (kb)
can be approximated by whitecap coverage
and wind speed (Asher et al., 1996), because
breaking waves generate bubble plumes and
whitecaps. Farmer et al. (1993) estimated
that the transfer velocity in storms is
approximately three times greater than that
suggested neglecting wave breaking and
bubbles. Perrie et al. (2004) showed that
related gas transfer velocities have a similar
variation during North Atlantic hurricanes.
Given the difficulty in making high wind
measurements (> 20 ms-1), gas exchange
estimates are largely extrapolated from less
challenging conditions. Moreover, kb depends
on the solubility as well as on molecular
diffusivity, and thus it differs from direct
transfer near the surface (Asher et al., 1996).
Significant Wave Height (SWH, m)
Gas exchange across the air-sea interface can
be viewed as turbulent transfer across two
fluid boundary layers, controlled by complex
physical and biochemical factors. As this
process is often driven by wind, the gas
transfer velocities are typically parameterized
in terms of wind speed. However,
uncertainties in parameterizations among
various transfer velocities are large, particularly
at high winds. Of particular importance to gas
exchange, especially for poorly soluble gases
such as oxygen (O2) and nitrogen (N2), is the
contribution of bubbles due to breaking
waves. Factors such as the super saturation
related to small bubbles and the transfer
velocity caused by these processes are not
well known (SOLAS Science Plan, 2004).
Figure 1: (a) Simulated wind speed (ms-1), SWH (m), and whitecap fraction (W, %), during storm event with the same y-axis scale; (b) calculated gas transfer velocities for O2,
using kT1 from Wanninkhof and McGillis (1999), kb from Woolf (1997), and kT2 from Zhao et al. (2003).
//21
partner projects
SOLAS Special Reports
The scientific challenges for IMBER-Intergrated
Marine Biochemistry and Ecosystem Research
The Pacific Islands – Global Ocean
Observing System (PI-GOOS)Understanding the ocean for sustainable
development in the South Pacific
The Pacific Ocean is the largest in the
world. Its open waters and coastal
environments are of strategic, economic,
environmental and social importance to
the Pacific Island Countries (PICs). The PICs
are most vulnerable and at risk to the
effects of accelerated climate change and
associated sea level rise. Significantly, the
El Niño Southern Oscillation (ENSO) is a
Pacific wide phenomenon that also
impacts the ecology, economy and social
structure of PICs. Increased vulnerability
and needs of PICs to acquire an integrated
and holistic approach to ensure sustainable
management and development of its
ocean environment, resources and related
climate issues led to the establishment of a
Pacific Islands (PI)-GOOS in 1998, a
‘spin-off’ from the Intergovernmental
Oceanographic Commission’s (IOC)
Global Ocean Observing System (GOOS)
established in response to the 1992
Earth Summit. PI-GOOS is dedicated to
developing capacity in oceanography
in the South Pacific region through a
framework within which the systematic
acquisition of oceanographic, marine
and related climate data, storage, analysis,
monitoring and forecasting is encouraged.
PI-GOOS works in collaboration with the
Pacific Islands Global Climate Observing
System (PI-GCOS), and the US Pacific
Integrated Ocean Observing System (IOOS)
to achieve this.
The PI-GOOS vision is to assist
development via improved capacity
building, long-term ocean observations
and delivery of useful products to the
region. Ultimately, this will enhance
the scientific information and advice
available to the region for improving
marine and coastal water quality;
agriculture development; coral reef
health; and climate observations
(disaster mitigation and preparedness).
The goal of IMBER is to
investigate the sensitivity of
marine biogeochemical cycles
and ecosystems to global
change, on time scales
ranging from years to
decades, due to the society’s need to understand and
respond to the impacts of climate change.
The IMBER Science Plan and Implementation Strategy is
structured around four major research themes. Theme 1
focuses on identifying and characterizing interactions
between key marine biogeochemical cycles and ecosystem
processes including the transformation of organic matter
in food webs; transfers of matter across ocean interfaces;
and material flow in end-to-end food webs.
Central to meet the IMBER goal is Theme 2 which will
develop a predictive understanding of how marine
biogeochemical cycles and ecosystems respond to
complex forcings, such as large-scale climatic variations
and changing physical dynamics, carbon cycle chemistry,
changes in nutrient fluxes, and the impacts of marine
harvesting. IMBER seeks an improved understanding of
the impacts of climate-induced changes such as
circulation, ventilation and stratification, and of seasonal
to inter-decadal variability on food web-biogeochemical
interactions. IMBER seeks a better understanding of the
expected CO2-driven changes in carbonate chemistry
and their effects on marine organisms and metabolism
and ultimately on biogeochemical cycles, ecosystems
and their interactions. In addition to this direct effect of
changing carbonate chemistry, IMBER also focuses on
the indirect changes via pH on the availability and
speciation of macro- and micronutrients and toxic trace
metals on ocean ecosystem structure and function.
Another forcing is the predicted two-fold increase in
nitrogen and phosphorus inputs from land to the ocean
A glimpse of the future ocean:
mesocosm perturbation experiments
The absorption of fossil-fuel CO2 into the world‘s oceans,
over the past two centuries, has led to an increase in
gaseous CO2 concentration and a decrease in pH and
carbonate ion concentration, which has, in turn, served to
lower the saturation state of seawater with respect to
biogenic calcite and aragonite (Sabine et al., 2004; Feely et
al., 2004). Although these changes in carbonate chemistry
of the upper ocean may seem small; in reality, they have
ample potential to cause changes in marine ecosystems.
by the middle of this century (Figure 1). How changes in
the abundance, distribution and stoichiometry of
nutrient elements affect food web structure and
function, and how will increases in hypoxia and anoxia
affect food webs and cycles of key macro- and
micronutrients, are central questions to IMBER.
The third theme focuses on the present and future
capacity of the ocean to control the climate system via
atmospheric composition and ocean heat storage. Key
scientific issues for this theme include (i) the varying
capacity of the ocean to store anthropogenic CO2; (ii)
ecosystem feedbacks on ocean physics and climate; and
(iii) impact of changes in low-oxygen zones on the
nitrogen cycle, especially transformations involving N2O.
Finally, Theme 4 integrates natural and social sciences,
drawing on information from the previous three
themes to investigate key interactions with the human
system and the options for mitigating or adapting to
the impacts of global change on marine
biogeochemical cycles and ecosystems.
Website: http://www.imber.info/
e-mail: imber@univ-brest.fr
Figure 1: Predicted riverine fluxes of dissolved inorganic
nitrogen for various regions in 1990 and 2050 for the
“business-as-usual” scenario. From Seitzinger et al. (2002).
Changes in the ocean influence not only the most sensitive
ecosystem components (e.g. acidification impacts on
calcifying organisms), but also those components which
interact with them; as predators, prey, competitors,
epibionts, etc. The transfer of effects through the
ecosystem may be dampened or amplified, depending on
the prevalence of negative or positive feedback loops.
Accordingly, system responses to changing environmental
conditions can be gradual or catastrophic (“regime shifts”),
including the potential for a complete reorientation of
biogeochemical cycles. The identification of sensitive
components, dampening and amplifying mechanisms, and
The information being acquired by
PI-GOOS is disseminated as useful
information for Pacific Island
governments, regional and international
scientific research and the public.
Dr Sarah Grimes, PI-GOOS Co-ordinator
(sarahg@sopac.org)
Mr Dean Solofa, PI-GOOS Co-ordinator
(dsalofo@sprep.org.ws)
Ms Eileen Shea, Director of the Pacific IOOS
Program (SheaE@EastWestCenter.org)
Photo: Pelagic ecosystem CO2 perturbation study (PeECE III; www.peece.ifm-geomar.de) in Large Scale Mesocosm
Facility of the University of Bergen, Norway, May/June 2005.
//22
experiment at the community level and may lead to a
renaissance in mesocosm experimentation. To ensure
comparability of the results from these experiments it will
be important to develop guidelines and quality standards
for mesocosm experiments. This should include
questions concerning extrapolation to the natural
system; addressing relevant scientific issues; optimal
mesocosm size for the plankton community considered;
closed versus open systems; and replication and controls.
To promote comparative studies on results from multiple
mesocosm experiment it will also be extremely helpful to
collect and archive the data centrally and make them
available to the scientific community.
Photo: Pelagic ecosystem CO2 perturbation study
(PeECE III; www.peece.ifm-geomar.de) in Large Scale
Mesocosm Facility of the University of Bergen,
Norway, May/June 2005.
feedback loops is urgently needed to develop scenarios for
future ecosystem functioning and biogeochemical cycles.
For an integrated understanding of the sensitivity of
marine systems to global change, there is a particular
need for manipulative experiments on the community
to ecosystem level. This can be achieved both in large
enclosures and open ocean in situ experiments. While
mesoscale in situ experiments are often not practical or
feasible for perturbations other than iron release.
Mesocosm perturbation studies, however, offer a
reasonable alternative, allowing the manipulation of
complex ecosystems in a semi-natural setting under a
range of oceanographic settings.
Recently a series of multinational mesocosm experiments
were conducted to examine the effects of future forcing
on marine pelagic ecosystems (e.g. Engel et al. 2005,
Delille et al. 2005, Kim et al. 2006). In the true spirit of
SOLAS, these experiments covered a wide range of
disciplines from marine chemistry, marine biology,
molecular & cell biology to biogeochemistry, atmospheric
chemistry, and earth system modelling. Results from these
experiments highlighted the sensitivity of key components
of the pelagic ecosystem to ocean acidification and
revealed associated biogeochemical feedback processes.
Studies on the effects of projected future forcings on
marine ecosystems will increasingly rely on manipulative
Despite their broad applicability, mesocosm experiments
have some significant limitations. Wall effects, unnatural
mixing regimes and turbulence levels, and the exclusion of
higher trophic levels create an environment which differs
from ambient conditions. Moreover, presently available
mesocosm facilities are either land-based or located nearshore. Mesocosm studies are therefore restricted to the
generally more robust coastal ecosystems. To allow testing
of ecosystems and processes most sensitive to ocean
change requires the development of mobile mesocosm
facilities which can be used in a variety of oceanographic
settings, including open ocean locations. The technology
for such a facility is presently under development as part
of the German SOLAS Programme SOPRAN (Surface
Ocean Processes in the Anthropocene). Another limiting
factor is the relatively short duration of mesocosm studies,
which due to wall effects and deviation of the enclosed
communities from the natural system, are restricted to
time scales of weeks to months. Like most experimental
studies mesocosm experiments therefore run short in
assessing long-term, chronic effects of environmental
perturbations. With increasing evidence now suggesting
microevolutionary adaptation to be a potentially important
dampening mechanism in response to global change, this
should be a top priority of future research in global
change biology. One possible strategy for gaining a
realistic assessment of this chronic effect is to artificially
bath a patch of ocean or coral reef with high CO2 levels
(Doney, 2006). Oceanographers are just beginning to
explore the feasibility of such manipulative experiments.
In spite of some limitations, in situ mesocosm perturbation
studies provide an effective tool to unravel the effects of
projected future forcing on natural aquatic ecosystems
and will provide the link between in vitro experiments and
field observations. As human-induced global change
continues to alter marine environmental conditions,
manipulative experiments at the community to whole
ecosystem level will become increasingly relevant.
Kitack Lee (ktl@postech.ac.kr)
Ulf Riebesell (uriebesell@ifm-geomar.de)
SOLAS International Summer School
Corsica, France 22 Oct - 3 Nov 2007
“The 2005 SOLAS Summer School
provided me with a valuable
experience. I was able to gain a
diverse impression of fields relating
to SOLAS science... I learned a lot from
discussions with lecturers and other
young scientists, who kindly offered
a great deal of advice and good ideas”
The SOLAS International Summer
School aims to expose doctoral
students and young scientists to
recent developments and
methodologies in the study of
biogeochemical and physical
feedbacks between the ocean
and the atmosphere.
Kai Zhang, Chinese Academy of Sciences
App. Deadline:
13 Apr 2007
http://www.uea.ac.uk/env/solas/summerschool
Institut d'Etudes
Scientifiques de Cargèse
partner projects
A joint SCAR/SCOR Expert Group on
Oceanography was formed in April 2005:
• to encourage an inter-disciplinary
approach to Southern Ocean (SO)
observations, modeling and research,
recognizing the interdependence of
physical, chemical and biological
processes at present and in the past;
• to facilitate coordination between the
research groups currently active and
those planning research in the SO;
• to identify historical and reference
data sets of value (initially physical
oceanography); and
• to encourage information exchange
with operational agencies.
The initial focus of the Group is on
physical oceanography, to ensure that a
comprehensive view is obtained of the
physics on which biological and chemical
processes depend. The Group is
co-chaired by Eberhard Fahrbach (SCAR),
and Eileen Hofmann (SCOR). SOLAS is
represented by Richard Bellerby.
The first meeting of the Group occurred
in Venice in October 2005 and covered
topics including collating physical
oceanographic data; promoting
interdisciplinary research in the SO; SO
observing systems; improving the
bathymetric database; data
management and exchange; and
developing a web site as a basis for
coordination. A second meeting was
held in Hobart in July 2006. Progress
was reported in collating physical
oceanographic data, in the
development of interdisciplinary
research under the ICED programme,
and in the development of a Southern
Ocean Observing System (SOOS).
SCAR’s involvement with the SO extends
to its co-sponsorship of programmes
such as the SO component of GLOBEC
and the new Integrated Analyses of
Circumpolar Climate Interactions and
Ecosystem Dynamics in the Southern
Ocean (ICED). SCAR is also linked to
iAnZone, which is an affiliated
programme under the SCAR/SCOR
Expert Group on Oceanography.
SCAR also has an Action Group for the
Census of Antarctic Marine Life (CAML),
which is funded by the Sloan
Foundation and has held a number of
planning meetings to gear up for
seagoing operations for IPY.
www.scar.org
//23
photo: Mengmei Lin
Invited plenary speakers:
Laurent Bopp, France
Jill Cainey, Australia
Colin Murrell, UK
Shigenobu Takeda, Japan
Barry Huebert, USA
Phil Nightingale, UK
Wuting Tsai, China (Taipei)
Kitack Lee, Korea
Tom Pedersen, Canada
Doug Wallace, Germany
Minhan Dai, China (Beijing)
Maurice Levasseur, Canada
Joyce Penner, USA
Roland Von Glasow, Germany
Laura Farias, Chile
Craig McNeil, USA
Eric Saltzman, USA
Andy Watson, UK
Véronique Garçon, France
Lisa Miller, Canada
Lise Lotte Sørensen, Denmark
Tong Zhu, China (Beijing)
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Issue 04 Autumn 2006

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