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Un registro de anillo de árbol de 2000 años de temperaturas anuales en las montañas de la Sierra Nevada
Science (New York, N.Y.)
|March 5, 1993
Resumen
Los datos de anillos de árboles revelan un ciclo de temperatura de 125 años en la Sierra Nevada, vinculado a la actividad solar. Este ciclo influyó en la Época Cálido Medieval y la Pequeña Edad de Hielo, con cambios de fase que posiblemente indican un comportamiento solar caótico.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Física solar Física solar es la física de la energía solar.
Sus antecedentes:
- La reconstrucción del clima pasado es crucial para comprender la dinámica climática a largo plazo.
- Los datos de anillos de árboles proporcionan un proxy valioso para las variaciones históricas de temperatura.
- La identificación de patrones cíclicos en el clima puede ayudar a vincularlos con factores de forzamiento externos como la actividad solar.
Objetivo del estudio:
- Para reconstruir un récord de temperatura de finales de temporada de 2000 años para la línea de la Sierra Nevada.
- Para identificar tendencias y periodicidades a largo plazo dentro de esta reconstrucción de la temperatura.
- Investigar posibles vínculos entre los ciclos climáticos identificados y la actividad solar.
Principales métodos:
- Análisis de los datos de anillos de árboles de un sitio de la línea de madera de Sierra Nevada.
- Reconstrucción de las temperaturas medias de finales de temporada (junio-enero) en los últimos 2000 años.
- Análisis espectral para identificar periodicidades y correlación con proxies de actividad solar (radiocarbono, registros aurorales).
Principales resultados:
- Se identificó una periodicidad significativa de 125 años en la reconstrucción de la temperatura.
- Este ciclo de 125 años se correlaciona con los períodos de actividad solar conocida.
- Tanto la Época Cálido Medieval como la Pequeña Edad de Hielo muestran una estrecha asociación con esta variación de temperatura de 125 años.
- Los cambios de fase en el ciclo de 125 años se alinean con los datos recientes de radiocarbono, lo que sugiere un comportamiento solar potencialmente caótico.
Conclusiones:
- La periodicidad de temperatura de 125 años en la Sierra Nevada está fuertemente vinculada a la actividad solar.
- Este ciclo impulsado por el sol jugó un papel en la configuración de los principales eventos climáticos como la época cálida medieval y la Pequeña Edad de Hielo.
- Los cambios de fase observados pueden indicar un comportamiento complejo y potencialmente caótico en la actividad del sol en escalas de tiempo milenarias.
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