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El engrosamiento persistente y generalizado de la capa de hielo de la Antártida Oriental por el congelamiento desde
Robin E Bell1, Fausto Ferraccioli, Timothy T Creyts
1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA. robinb@ldeo.columbia.edu
Science (New York, N.Y.)
|March 10, 2011
Resumen
Congelamiento generalizado debajo de la Antártida Oriental.
Área de la Ciencia:
- Glaciología glaciología.
- La geofísica es la geofísica.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- El crecimiento de las capas de hielo es impulsado principalmente por la acumulación de nieve en la superficie.
- Los procesos subglaciales pueden tener un impacto significativo en la dinámica de las capas de hielo.
- La comprensión de la formación de hielo basal es crucial para el modelado preciso de la capa de hielo.
Objetivo del estudio:
- Para investigar el alcance y el impacto de la congelación basal en la Antártida Oriental.
- Para analizar los mecanismos que impulsan la formación de hielo subglacial.
- Para evaluar cómo el congelamiento influye en el balance de masa y la dinámica de la capa de hielo.
Principales métodos:
- Investigación aerogeofísica durante el Año Polar Internacional.
- Análisis de la composición y el grosor de la base de la capa de hielo.
- Modelado del comportamiento del agua subglacial y la formación de hielo.
Principales resultados:
- El 24% del área de la base de la capa de hielo debajo del Domo A muestra evidencia de congelación.
- En algunas áreas, la congelación basal representa hasta el 50% del grosor del hielo.
- El congelamiento es el resultado del enfriamiento y súper enfriamiento del agua subglacial cerca de las crestas montañosas y las paredes de los valles.
Conclusiones:
- El congelamiento basal es un proceso significativo que impulsa la redistribución masiva en la Antártida Oriental.
- El congelamiento altera la reología del hielo, deforma la capa de hielo e impacta en los archivos climáticos.
- Es posible que los modelos actuales de las capas de hielo no capturen completamente los efectos de la congelación basal en el flujo de hielo.
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