Climate Variability and Change—Hydrological Impacts (Proceedings of the Fifth FRIEND World Conference held at Havana, Cuba, November 2006), IAHS Publ. 308, 2006, 479–482.


 

El glaciar 15 del Antisana: investigaciones glaciológicas y su relación con el recurso hídrico

                                    

BOLIVAR CACERES1, BERNARD FRANCOU2, VINCENT FAVIER2, GUILLAUME BONTRON2, PIERRE TACHKER2, RODOLPHE BUCHER2, JEAN DENIS TAUPIN2, MATHIAS VUILLE3, LUIS MAISINCHO1, FANNY DELACHAUX4, JEAN PHILIPPE CHAZARIN4, ERIC CADIER4 & MARCOS VILLACIS4

 

1 INAMHI, Iñaquito, 700 y Corea, Quito, Ecuador

bolivarc@inamhi.gov.ec

2 IRD, CP 9214, La Paz, Bolivia

3 Climate System Research Center, Departament of Geosciences. University of Massachusetts, Amherst, Massachusetts, USA

4 IRD, Whymper 442 y Coruña , Quito, Ecuador

 

Resumen Sobre el área de ablación de un glaciar del Antisana, el balance de masa ha sido medido a una escala mensual, proveyendo interesantes detalles acerca del patrón estacional que se encuentra en estos ambientes contrastados. Información no continua acerca de la recesión del hielo se la puede encontrar para las décadas anteriores. Los datos recogidos muestran una aceleración clara en el derretimiento de los glaciares desde comienzos de los ochenta:. La situación es particularmente  dramática para los glaciares de pequeño tamaño (<1 km2) los cuales podrían desaparecer en los próximos cinco años. Durante la década pasadas (noventa) las tasas de ablación fueron en promedio altas, llegando a ser  más intensas durante la fase cálida de el ENSO (El Niño). Esta situación es analizada en relación con las peculiares condiciones climáticas que han prevalecido en los trópicos durante los últimos 25 años: un incremento en la temperatura sobre la mediana troposfera en alrededor de 1°C, relacionado a un largo período de incremento en la temperatura superficial del mar. Los glaciares tropicales se muestran como claros indicadores del calentamiento global y la variabilidad climática a una escala mundial y regional.

 

Palabras claves glaciares; balance; ablación; ENSO; clima

 


 

Glacier 15, Antisana, Ecuador: its glaciology and relations to water resources

 

 

Abstract Besides the Lewis glacier in Kenya, Glacier 15 of Antisana, Ecuador (5760–4830 m, 0.28 km2) is the only one which provides regular information regarding glacier mass balance near to the Equator (Annual Report of the World Services for the Monitoring of Glaciers, WGMS 2005) to the scientific community. The surface of the glacier had been re-constructed using aerial-photogrammetry from 1956 to 1997. Since 1994, direct measurements have been taken over the terminal zone at the glacier tongue using topography. That process has shown the changes at the glacier limits and has determined the superficial speed at the terminal zone of the tongue (ablation zone). At the ablation zone (<5100 m) a wide net of stakes have been installed in order to measure the evolution of the glacier mass each month since 1995. In addition, holes to measure accumulation have been dug in the ablation zone at the end of the hydrological year (December–January) in order to calculate the net specific annual balance. Glacier 15 has lost an average of 600 mm of water a year since 1995 (11 years). The inter-annual variation is wide: very negative balances were observed in 1995 and 2002, two positive balances in 1999 and 2000, and negative balances for the remaining years. The dynamics of the glacier show a mass balance with very noticeable fluctuations. These variations are well synchronized with the glacier evolution. The variability of the ENSO (El Niño Southern Oscillation) has been an important factor in controlling the mass evolution of the Ecuadorian glaciers and the climate conditions. Those factors caused advances and retreats on the glaciers according to La Niña (cold event) or El Niño (warm event), respectively. This study has shown the relationship between glaciology and availability of hydrological sources.

 

Key words  glacier; balance; abalation; ENSO; climate