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El calentamiento temprano de la América del Sur tropical en la última transición glacial-interglacial
G O Seltzer1, D T Rodbell, P A Baker
1Department of Earth Sciences, Syracuse University, 204 Heroy Geology Laboratory, Syracuse, NY 13244, USA. goseltze@syr.edu
Science (New York, N.Y.)
|June 1, 2002
Resumen
Los glaciares tropicales de los Andes retrocedieron hace 22.000 a 19.500 años, lo que indica un calentamiento significativo en el hemisferio norte. Esta deglaciación, impulsada por la temperatura, ocurrió antes de los eventos de calentamiento de América del Norte y Europa.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Glaciología glaciología.
- Historia del clima andino historia del clima andino
Sus antecedentes:
- La glaciación tropical andina es un indicador clave de los cambios de temperatura en el pasado.
- Comprender el momento de la deglaciación es crucial para la reconstrucción del clima.
Objetivo del estudio:
- Para determinar el momento de la deglaciación en los Andes tropicales.
- Para investigar la relación entre la deglaciación andina tropical y los eventos climáticos del hemisferio norte.
Principales métodos:
- Análisis sedimentológico de núcleos de lagos de los Andes tropicales.
- La datación por radiocarbono de los depósitos glaciales.
Principales resultados:
- La deglaciación en los lagos Titicaca y Junin ocurrió entre 22.000 y 19.500 años calendario antes del presente.
- Esta deglaciación es anterior al calentamiento de Bølling-Allerød y a la deglaciación de América del Norte por varios miles de años.
- Los Andes tropicales experimentaron deglaciación bajo condiciones persistentemente húmedas.
Conclusiones:
- La temperatura media anual es el principal impulsor de la glaciación en los Andes tropicales.
- La desglaciación tropical andina precedió al calentamiento del hemisferio norte, lo que sugiere una compleja dinámica climática interhemisférica.
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