INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
capítulos de libros
4.2 Special Events. Argentina (AR). Horcones Inferior (AR 5005) glacier surge
L.E. ESPIZUA, P. PITTE AND L. FERRI HIDALGO
Fluctuations of Glaciers 2000-2005. Vol. IX
ICSU (FAGS)-IUGG (IACS)-UNEP-UNESCO-WMO.
Lugar: Zurich; Año: 2008; p. 43 - 44
The Horcones Inferior glacier is located at 32º40´S latitude and 70º00´W longitude at the south wall of Cerro Aconcagua (6,959 m a.s.l.), the highest peak in the Western Hemisphere. It is a valley glacier covered by debris with thermokarst features, that flows to the southeast. Between 1963 and 1984 the glacier front position did not show significant changes. The glacier had a surge between 1984 and 1986 and stopped in 1989. It was about 10,5 km long between 1990 and 1997. From 1997 to 1999 the glacier retreated 130 m based on field observation (Happold and Schrott, 1993; Unger et al., 2000; 2005). A new surge event occurred in 2004. The evolution of the surge front was detected through analysis of Landsat images and field observations. We can not establish the exact time when the surge began, but on the image of 13 February 2003, in the upper part of the glacier at 4175 m a.s.l., a wave of uncovered and covered ice advanced 320 m since 10 February 1999. Between the images of 13 February 2003 and 8 February 2004, the ice-wave advanced 5.140 m with a mean velocity of 14.3 m/day on the debris covered glacier. It reached an altitude of 3910 m a.s.l., 360 m upstream from the stable front position that the glacier had in 2001, 2003 and 2004. On the image of 25 January 2005, the surge advanced 3000 m with a mean velocity of 8.5 m/day and surpassed the previous front position. The satellite image of 28 January 2006, shows that the surge front advanced 440 m with a mean velocity of 1.2 m/day.The resulting flow variations are given in Table B and BB. Happoldt, H. and Schrott, L., 1993. Horcones Inferior. In: IAHS/UNESCO (1993). Fluctuations of Glaciers 19851990. Volume VI, pp 70. Zurich: World Glacier Monitoring Service. Haeberli, W., Hoelzle, M. (Eds). Unger, C., Espizua, L. E. and Bottero, R., 2000. Untersuchung von Gletscherständen im tal des Río Mendoza (Zentralargentinische Anden) Kartierung eines Surge-Vorstosses des Horcones Inferior. Zeitschrift für Gletscherkunde und Glazialgeologie. Band 36, S, 151-157. Unger, C., Espizua, L. E. and Bottero, Horcones Inferior, 2005. In: IAHS (ICSI) UNEP UNESCO, (2005). Fluctuations of Glaciers 1995-2000. Volume VIII, pp 288. Zurich: World Glacier Monitoring Service, Haeberli, W., Zemp, M., Frauenfelder, R., Hoelzle, M., Kääb, A. (Eds.).