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La variación cíclica y el forzamiento solar del clima del Holoceno en el subartico de Alaska
Feng Sheng Hu1, Darrell Kaufman, Sumiko Yoneji
1Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA. fshu@life.uiuc.edu
Science (New York, N.Y.)
|September 27, 2003
Resumen
El clima del Holoceno en Alaska mostró variaciones cíclicas relacionadas con la actividad solar. Estos cambios impulsados por el sol impactaron los ecosistemas del norte y sugieren cambios climáticos similares en todo el Atlántico Norte y el Pacífico Norte.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Geología Cuaternaria Geología Cuaternaria
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- La variabilidad del clima del Holoceno es crucial para comprender el sistema climático de la Tierra.
- Las regiones de altas latitudes son indicadores sensibles del cambio climático global.
- La influencia de la actividad solar en el clima regional sigue siendo un área activa de investigación.
Objetivo del estudio:
- Para investigar el clima del Holoceno y la dinámica del ecosistema en el suroeste de Alaska.
- Para identificar periodicidades en las variaciones climáticas y su correlación con la actividad solar.
- Para comparar los cambios climáticos del Holoceno entre las regiones del Atlántico Norte y el Pacífico Norte.
Principales métodos:
- Análisis de alta resolución de núcleos de sedimentos de lagos del suroeste de Alaska.
- Análisis espectral para identificar variaciones y periodicidades cíclicas.
- Análisis de correlación con series temporales de núcleos cosmogénicos (carbono-14 y berilio-10) y hielo a la deriva del Atlántico Norte.
Principales resultados:
- Los registros de sedimentos del lago revelan distintas variaciones cíclicas del clima y los ecosistemas durante el Holoceno.
- Estas variaciones exhiben periodicidades consistentes con los ciclos de actividad solar.
- Se observó coherencia entre los datos climáticos de Alaska, los registros de nucleidos cosmogénicos y los datos de hielo a la deriva del Atlántico Norte.
Conclusiones:
- Las variaciones de la irradiación solar influyeron significativamente en el clima y los ecosistemas del Holoceno en entornos de latitudes altas del norte.
- Los cambios climáticos a escala centenaria en el Atlántico Norte subpolar y el Pacífico Norte fueron sincrónicos.
- Los vínculos entre el sol, el océano y el clima probablemente jugaron un papel clave en la sincronización de estos cambios climáticos hemisféricos.
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