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Señales de baja frecuencia en cronologías largas de anillos de árboles para reconstruir la variabilidad de
Jan Esper1, Edward R Cook, Fritz H Schweingruber
1Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland.
Science (New York, N.Y.)
|March 23, 2002
Resumen
Los registros de anillos de árboles largos son vitales para comprender la variabilidad climática pasada y el Período Cálido Medieval (PCM). Nuestro estudio muestra que los datos de anillos de árboles del hemisferio norte pueden preservar las tendencias de temperatura de varios siglos, apoyando el MWP.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Dendrocronología Dendrocronología.
Sus antecedentes:
- La reconstrucción precisa de la variabilidad climática pasada es esencial para comprender las tendencias de temperatura a largo plazo.
- El Período Cálido Medieval (PCM) y el calentamiento del siglo XX requieren registros climáticos robustos y a largo plazo para su comparación.
- Las cronologías de anillos de árboles ofrecen un valioso sustituto para reconstruir las condiciones climáticas pasadas.
Objetivo del estudio:
- Para demostrar la capacidad de las cronologías de anillos de árboles extratropical del hemisferio norte en la preservación de la variabilidad climática multicentenaria.
- Para validar el uso de datos de anillos de árboles para reconstruir las tendencias de temperatura en los últimos 1000 años.
- Para evaluar la ocurrencia a gran escala del Período Cálido Medieval utilizando evidencia de anillos de árboles.
Principales métodos:
- Selección de 14 cronologías de anillos de árboles de alta calidad de sitios extratropicos del hemisferio norte.
- Aplicación de métodos analíticos apropiados para preservar las tendencias de temperatura a gran escala y multicentenarias.
- Promedio de las cronologías seleccionadas para crear un registro compuesto.
Principales resultados:
- Las cronologías de anillos de árboles cuidadosamente seleccionadas pueden preservar tendencias de temperatura coherentes, a gran escala y multicentenarias.
- Los métodos desarrollados aseguran la preservación de la variabilidad climática crítica en los datos de anillos de árboles.
- El registro compuesto de anillos de árboles apoya la ocurrencia del Período Cálido Medieval en todo el hemisferio norte extratropical.
Conclusiones:
- Los registros de anillos de árboles son una fuente confiable para reconstruir la variabilidad de la temperatura pasada en escalas de tiempo multicentenarias.
- El estudio valida el uso de datos de anillos de árboles para comprender eventos climáticos históricos como el MWP.
- Los hallazgos apoyan la naturaleza a gran escala del Período Cálido Medieval en los extratropicos del Hemisferio Norte.
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