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Los cambios en la elevación de la capa de hielo de Groenlandia se atribuyen principalmente a la variabilidad de la
McConnell1, Arthern, Mosley-Thompson
1Desert Research Institute, University & Community College System of Nevada, Reno 89512, USA. jmcconn@dri.edu
Nature
|September 6, 2000
Resumen
Los cambios en la elevación de la capa de hielo de Groenlandia entre 1978 y 1988 fueron impulsados por la variabilidad de la acumulación de nieve, que no excedió las fluctuaciones climáticas naturales. El monitoreo a largo plazo de la elevación de la capa de hielo y la acumulación de nieve es crucial para comprender los cambios de masa.
Área de la Ciencia:
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Ciencias del Sistema Terrestre Ciencias del Sistema Terrestre
Sus antecedentes:
- La respuesta de las capas de hielo al cambio climático impacta significativamente el aumento futuro del nivel del mar.
- Los datos satelitales revelan variabilidad espacial en la elevación de la capa de hielo de Groenlandia, pero los procesos geofísicos siguen sin estar claros.
- Es esencial distinguir los cambios recientes en la capa de hielo de la variabilidad natural.
Objetivo del estudio:
- Para determinar los cambios de elevación de la capa de hielo en el sur de Groenlandia entre 1978-88.
- Identificar los procesos geofísicos responsables de los cambios de elevación observados.
- Evaluar si los cambios recientes se encuentran dentro de la variabilidad climática natural de Groenlandia.
Principales métodos:
- Utilizó un modelo de densificación de firn basado en la física.
- Se reconstruyó la acumulación anual de nieve utilizando datos de 12 núcleos de hielo de gran altitud.
- Comparó los cambios de elevación modelados con mediciones por satélite contemporáneas.
Principales resultados:
- Los cambios de elevación modelados impulsados por la acumulación coincidieron estrechamente con las observaciones satelitales para 1978-88.
- Atribuyó los cambios de elevación observados a las variaciones en la acumulación de nieve.
- Los análisis de núcleos de hielo más largos indicaron una variabilidad típica dentro de los límites naturales para la capa de hielo de Groenlandia.
Conclusiones:
- La variabilidad de la acumulación de nieve fue el principal impulsor de los cambios de elevación de la capa de hielo de Groenlandia en la década de 1978-88.
- Los cambios observados estaban dentro de la variabilidad natural a largo plazo de la capa de hielo.
- Las mediciones integradas a largo plazo de la elevación de la superficie de la capa de hielo y la acumulación de nieve son necesarias para evaluaciones integrales del balance de masas.
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