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Balance de masas de la capa de hielo de Groenlandia en altitudes elevadas
1EG&G Services, Wallops Flight Facility, Building N-159, Wallops Island, VA 23337, USA. Jet Propulsion Laboratory, M/S 300-325, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. Byrd Polar Research Center, Ohio State University, Columbus, OH 42310, USA. ESSIC, University of Maryland, College Park, MD 20742, USA. Radar Systems and Remote Sensing Laboratory, University of Kansas, Lawrence, KS 66045, USA.
Science (New York, N.Y.)
|July 21, 2000
Resumen
La capa de hielo de Groenlandia muestra variaciones regionales en los cambios de espesor del hielo en las últimas décadas. Mientras que algunas áreas se están engrosando, otras, particularmente el sureste, se están adelgazando significativamente.
Área de la Ciencia:
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima
- Ciencias del Sistema Terrestre Ciencias del Sistema Terrestre
Sus antecedentes:
- El equilibrio de masa de la capa de hielo de Groenlandia es crucial para comprender el aumento global del nivel del mar.
- Las estimaciones anteriores de las tasas de engrosamiento y adelgazamiento del hielo han mostrado variabilidad regional.
Objetivo del estudio:
- Para comparar la descarga de hielo con la acumulación de nieve en toda la capa de hielo de Groenlandia.
- Para estimar las tasas de espesamiento y adelgazamiento del hielo en las últimas décadas.
Principales métodos:
- Comparando la descarga de hielo de las zonas de gran altitud con la acumulación total de nieve.
- Utilizando datos de encuestas repetidas con altímetros.
Principales resultados:
- La capa de hielo de Groenlandia está, en promedio, en equilibrio.
- Existen variaciones regionales significativas: engrosamiento de 21 cm/año en el suroeste, adelgazamiento de 30 cm/año en el sureste.
- El norte muestra menos variabilidad: 2 cm/año de engrosamiento (noreste) y 5 cm/año de adelgazamiento (noroeste).
- Las discrepancias observadas en el extremo sur en comparación con los datos de la encuesta de altimetro.
Conclusiones:
- La capa de hielo de Groenlandia exhibe dinámicas regionales complejas en su balance de masas.
- El sureste de Groenlandia está experimentando una pérdida sustancial de hielo, lo que contribuye a las preocupaciones sobre el aumento del nivel del mar.
- Los datos del altímetro pueden requerir refinamiento en regiones específicas del extremo sur.
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