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Contribuciones similares de agua de deshielo a los cambios del nivel del mar glacial de las capas de hielo antárticas
Eelco J Rohling1, Robert Marsh, Neil C Wells
1Southampton Oceanography Centre, Southampton SO14 3ZH, UK. e.rohling@soc.soton.ac.uk
Nature
|August 27, 2004
Resumen
Durante el último período glacial, las capas de hielo de la Antártida y el hemisferio norte contribuyeron por igual al aumento del nivel del mar. Esta investigación cuantifica las contribuciones de agua de deshielo de ambas regiones polares.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Glaciología glaciología.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- El período comprendido entre hace 75.000 y 20.000 años experimentó una variabilidad significativa del clima y del nivel del mar.
- Los escombros de las balsas de hielo del Océano Sur indican que el agua de deshielo de la Antártida influyó en los cambios en el nivel del mar, junto con las contribuciones de las capas de hielo del norte.
Objetivo del estudio:
- Para determinar las contribuciones relativas de las aguas de deshielo de la Antártida y las capas de hielo del norte a los cambios en el nivel del mar.
- Para simular el impacto de diferentes liberaciones de agua de fusión en las distribuciones de isótopos de oxígeno marino.
Principales métodos:
- Utilizó un modelo de complejidad intermedia para simular las liberaciones de agua de deshielo de las regiones polares.
- Simulaciones de modelos comparadas con datos de isótopos de oxígeno de núcleos de sedimentos.
Principales resultados:
- Se deduce que las capas de hielo antárticas y del norte contribuyeron aproximadamente por igual a la subida del nivel del mar entre 65.000 y 35.000 años atrás.
- Cada región polar contribuyó con un estimado de 15 m al aumento del nivel del mar durante este período.
Conclusiones:
- El estudio proporciona información cuantitativa sobre las fuentes de agua de deshielo durante las fluctuaciones pasadas del nivel del mar.
- La reducción inferida del volumen de hielo antártico es comparable a la de Meltwater Pulse 1A durante la última deglaciación.
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