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Grandes fluctuaciones en la velocidad en el glaciar Jakobshavn Isbrae de Groenlandia
Ian Joughin1, Waleed Abdalati, Mark Fahnestock
1Jet Propulsion Lab, California Institute of Technology, USA. ian@apl.washington.edu
Nature
|December 4, 2004
Resumen
Groenlandia: Groenlandia es el nombre de la isla.
Área de la Ciencia:
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima
- La detección remota con sensores.
Sus antecedentes:
- El balance de masa de la capa de hielo de Groenlandia está influenciado por las tasas de flujo de los glaciares de salida.
- Jakobshavn Isbrae, el glaciar de salida más grande de Groenlandia, ha sido estudiado repetidamente desde 1991.
- Comprender los cambios de velocidad de los glaciares es crucial para las evaluaciones del balance de masa de la capa de hielo.
Objetivo del estudio:
- Para medir la velocidad de Jakobshavn Isbrae entre 1992 y 2003 utilizando datos de teledetección.
- Para analizar las variaciones temporales en la velocidad de flujo de los glaciares.
- Para evaluar el impacto de los cambios de velocidad de los glaciares en la descarga de hielo.
Principales métodos:
- Utilizó datos de teledetección para mediciones de velocidad.
- Se analizaron los datos de velocidad de los glaciares de 1992 a 2003.
- Cambios de velocidad correlacionados con el engrosamiento y el adelgazamiento de los glaciares.
Principales resultados:
- Se detectó una variabilidad temporal significativa en la velocidad de Jakobshavn Isbrae.
- Se observó una disminución en la velocidad de 1985 a 1992, seguida de un aumento sustancial en 2003.
- Los cambios de velocidad se alinean con los patrones observados de engrosamiento y adelgazamiento de los glaciares.
Conclusiones:
- Los glaciares de rápido flujo pueden alterar significativamente la descarga de hielo en escalas de tiempo sub-decenales.
- La dinámica de la velocidad de los glaciares indica un potencial de respuesta rápida al cambio climático.
- Los cambios recientes en la velocidad de Jakobshavn Isbrae resaltan su sensibilidad a los cambios climáticos.
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