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Las fluctuaciones de alta frecuencia de los glaciares del Holoceno en Nueva Zelanda difieren de la firma del norte
Joerg M Schaefer1, George H Denton, Michael Kaplan
1Geochemistry, Lamont-Doherty Earth Observatory (LDEO), Palisades, NY 10964, USA. schaefer@ldeo.columbia.edu
Science (New York, N.Y.)
|May 2, 2009
Resumen
Fluctuaciones de los glaciares del Holoceno en Nueva Zelanda.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Glaciología glaciología.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Los tiempos y las causas del cambio climático interhemisférico durante el Holoceno son poco conocidos.
- La reconstrucción de las dinámicas climáticas del pasado requiere registros paleoclimáticos de alta resolución.
Objetivo del estudio:
- Para investigar las fluctuaciones de los glaciares del Holoceno en los Alpes del Sur de Nueva Zelanda.
- Para establecer una cronología de alta resolución de estos eventos.
- Para entender los impulsores de estos cambios climáticos.
Principales métodos:
- Cronología del berilio-10 (10Be) de alta resolución.
- Análisis de las fluctuaciones de los glaciares en los últimos 7000 años.
- Comparación con los patrones climáticos del hemisferio norte.
Principales resultados:
- Al menos cinco eventos de avance de glaciares ocurrieron en el último milenio.
- Las extensiones de los glaciares disminuyeron desde el Holoceno medio hasta el final.
- Los avances de los glaciares de Nueva Zelanda coincidieron con los períodos cálidos del hemisferio norte.
Conclusiones:
- La dinámica de los glaciares del Holoceno en Nueva Zelanda contrasta con los patrones del hemisferio norte.
- Es probable que los mecanismos regionales hayan influido en el clima de Nueva Zelanda.
- Los cambios en la circulación atmosférica del suroeste del Pacífico pueden haber impulsado estas fluctuaciones.
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