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Holoceno - Pleistoceno tardío registros climáticos de núcleos de hielo de núcleos de hielo de la meseta
Science (New York, N.Y.)
|October 27, 1989
Resumen
Los registros climáticos de la capa de hielo de Dunde en China muestran que la última etapa glacial fue más fría y húmeda. Las últimas décadas se encuentran entre las más cálidas, coincidiendo con los máximos del Holoceno.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Los núcleos de hielo proporcionan archivos invaluables de las condiciones climáticas pasadas.
- La meseta Qinghai-Tibet es una región crítica para comprender la dinámica climática asiática.
Objetivo del estudio:
- Para reconstruir los cambios climáticos subtropicales durante el Holoceno y la última etapa glacial (LGS).
- Para comparar las condiciones climáticas del LGS con las de la época del Holoceno.
Principales métodos:
- Análisis de tres núcleos de hielo profundos perforados en el lecho rocoso de la capa de hielo de Dunde.
- Examen de la composición isotópica (delta(18) O), el contenido de polvo, los aerosoles solubles y el tamaño de los cristales de hielo.
Principales resultados:
- Las condiciones de la última etapa glacial se caracterizaron por temperaturas más frías, mayor precipitación y mayores niveles de polvo en comparación con el Holoceno.
- Cambios significativos en las proporciones de delta ((18) O, las concentraciones de polvo, los aerosoles solubles y el tamaño de los cristales de hielo marcan la transición del LGS al Holoceno.
- Estos rápidos cambios climáticos ocurrieron hace aproximadamente 10.000 años.
- Los últimos 60 años representan uno de los períodos más cálidos en todo el registro de núcleos de hielo, comparable al máximo térmico del Holoceno.
Conclusiones:
- Los núcleos de hielo de la capa de hielo de Dunde ofrecen una representación detallada de la variabilidad del clima subtropical en las últimas decenas de miles de años.
- Los rápidos cambios climáticos ocurrieron al final del último período glacial, impactando el clima de la región.
- La reciente tendencia al calentamiento pone de relieve cambios significativos en el sistema climático actual.
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