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Efecto de la sedimentación en la estabilidad de la capa de hielo en la línea de conexión a tierra
Richard B Alley1, Sridhar Anandakrishnan, Todd K Dupont
1Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA. rba6@psu.edu
Science (New York, N.Y.)
|March 3, 2007
Resumen
La sedimentación debajo de las plataformas de hielo estabiliza las capas de hielo contra el aumento del nivel del mar. La reciente pérdida de hielo en la Antártida probablemente se deba al calentamiento, no a los cambios en el nivel del mar.
Área de la Ciencia:
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Geología Geología Geología.
Sus antecedentes:
- Las plataformas de hielo juegan un papel crucial en la estabilización de las capas de hielo.
- El retroceso de la línea de conexión a tierra es un indicador clave de la inestabilidad de la capa de hielo.
- El aumento del nivel del mar puede afectar la dinámica de las capas de hielo.
Objetivo del estudio:
- Para investigar el papel de la sedimentación en la estabilización de las capas de hielo.
- Para determinar la causa de la reciente pérdida de masa de hielo antártico.
- Para evaluar la influencia de los cambios pasados del nivel del mar en el comportamiento de la capa de hielo.
Principales métodos:
- Análisis de los procesos de sedimentación debajo de las plataformas de hielo.
- Modelado de las respuestas de la capa de hielo a las fluctuaciones del nivel del mar.
- Interpretación de datos paleoclimáticos relacionados con las edades de hielo.
Principales resultados:
- La sedimentación proporciona una retroalimentación estabilizadora para las capas de hielo contra el aumento moderado del nivel del mar.
- La reciente pérdida de masa de la capa de hielo antártica no está impulsada principalmente por el aumento del nivel del mar.
- Los eventos significativos de aumento del nivel del mar, a diferencia de los cambios recientes, pueden abrumar las retroalimentaciones estabilizadoras.
Conclusiones:
- La sedimentación es un factor crítico para mantener la estabilidad de la capa de hielo.
- Las tendencias de calentamiento son la causa más probable de la actual pérdida de hielo antártico.
- Los cambios pasados a gran escala en el nivel del mar tuvieron diferentes impactos en las capas de hielo que los cambios actuales, más pequeños.
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