Subdirección de Ciencias de la Atmósfera e Hidrósfera

Subdirección de Ciencias de la Atmósfera e Hidrósfera
“6ta reunión científica del Observatorio HYBAM”
(26-30 de Octubre de 2015), Cusco, Perú
Critical erosion rates in mountain catchments during extreme
El Niño events: from the west central Andes to the Pacific
Ocean (Peru)
Investigadores:
S.B. Morera;
Morera Crave, A.; Guyot, J-L.; Desiderio, A.; Grover, O.; Salinas, F.; Gálvez C. and
Condom, T.
Colaboradores:
How do variations in sediment flux depend on extreme El Niño events?
Water resource
21.8 % whole country
65% Population
Objective
 Characterize the spatio-temporal
variation in SSY dynamics in
mountain catchments along the
western.
 Identifying sediment flux influence
during the extreme El Niño events
(1982-83 and 1997-98).
(Armijos et al., 2013; Guyot et al., 1996; Laraque et al., 2009; Morera et al., 2013; Pépin, 2007; Pepin et al., 2013;
Restrepo and Kjerfve, 2004; Restrepo et al., 2006; Tarras-Wahlberg and Lane, 2003)
2
Study area and geographic settings
- 20 Catchments
- Altitude (15 – 6768 masl)
- Area (638 -17 000 km2)
• Records (1 a 70 años)
-
River level (C) >> Hourly
Gauging (Q) >> 2 day - monthly
Suspended sediment
(SSC) >>> 4 hours to 10 days
Turbidity >> 6 hours
* ORE- HYBAM
* ESPECIAL PROJECT
3
Methodology
Estación Condorcerro
4
Strong spatial gradient in precipitation and runoff
Without extreme El
Niño events
5
Intra-annual variability and extreme events (1963-2014)
Daily variation
El Tigre
Water discharge
Water discharge
Seasonal variation
6
Water discharge greater than 1200 m3.s-1
Desborde del río Tumbes inunda más de 7.500 hectáreas
Domingo 29 de marzo del 2015
Hydrology characterization (PDF)
7
Suspended Sediment Rating Curve
SSY (t/d)
Santa Catchment
Water discharge (m3/s)
8
RUNOFF AND SPECIFIC SSY SPATIAL VARIATION
Without El Niño
Specific suspended sediment flux
RUNOFF
Without El Niño
9
Extreme climate conditions during El Niño (1982-83, 1997-98)
Infraestructura Hidráulica/Riego
Inundaciones cuenca media. Fuente:
Agencia Andina
Canal Vía seco. Fuente, Municipalidad de Sullana.
Suspended Sediment Rating Curve evolution
X segundo a la altura de la
de estación S. Cerro
Cuenca ChiraChira-Piura
20 toneladas/cu
toneladas/cu
2472
¿Cuanto se transporto durante El Niño 19821982-83 (3367 m3.s-1)?
??
?
11
Hydrology responds
7
Abbühl et al., 2010.
19
12
EROSION RATES DURING EL NIÑOS EVENTS (82-83, 97-98)
Strong influence, which increases
from 5 to 60 times SSY average
13
CONCLUSION AND FUTURE WORK
 First estimation of the SSY variability along the Pacific Peruvian
cost.
 Long-term Q and SSC variability have also been observed in Peru.
 The water discharge (runoff) gradient ranges from 2.4 to 25.3 l.km2.year-1
and specific SSY ranges from 26 to 1948 t.km-2.year-1.
 The extreme El Niño events (82-83, 97-98) the SSY increase from 3
to 60 times the historic annual average.
 The extreme El Niño events (82-83, 97-98) control sediment yield
in the north of Peru!
14
¡GRACIAS POR SU ATENCIÓN!
S. B. MORERA.
smorera@igp.gob.pe