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Un registro de temperatura de 3620 años de Fitzroya cupressoides anillos de árboles en el sur de América del Sur Sur
Science (New York, N.Y.)
|May 21, 1993
Resumen
Un registro de 3.622 años de árbol alerce de Chile revela fluctuaciones de temperatura a largo plazo. El estudio no encontró evidencia de un reciente calentamiento antropogénico en el sur de América del Sur, lo que pone de relieve la variabilidad natural del clima.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Dendrocronología Dendrocronología
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Comprender la variabilidad climática pasada es crucial para contextualizar el cambio climático actual.
- Las cronologías de anillos de árboles proporcionan datos proxy de alta resolución para reconstruir temperaturas pasadas.
- Los árboles Alerce (Fitzroya cupressoides) en el sur de Chile ofrecen un archivo único para estudios climáticos a largo plazo.
Objetivo del estudio:
- Para reconstruir un récord de temperatura de verano de 3,622 años para el sur de América del Sur utilizando anillos de árboles de alerce.
- Investigar las tendencias de temperatura a largo plazo e identificar períodos de calentamiento y enfriamiento significativos.
- Evaluar la evidencia del calentamiento antropogénico en la región basándose en datos indirectos e instrumentales.
Principales métodos:
- Construcción de una cronología de anchos de anillos de árboles resuelta anualmente de Fitzroya cupressoides.
- Calibración de los datos de los anillos de los árboles con respecto a los registros de temperatura instrumentales.
- Análisis de la reconstrucción de la temperatura de 3.622 años para identificar patrones y anomalías a largo plazo.
Principales resultados:
- El intervalo más largo de temperaturas de verano por encima de la media se produjo a partir del 80 a.C. hasta el año 160 d.C.
- Se observaron períodos prolongados de temperaturas por debajo de la media de 300 a 470 y de 1490 a 1700.
- Ni los datos de los anillos de los árboles de Alerce ni los registros instrumentales muestran evidencia de calentamiento antropogénico en las últimas décadas para el sur de América del Sur (35-44 ° S).
Conclusiones:
- Los árboles de Alerce proporcionan un valioso sustituto a largo plazo para reconstruir el clima pasado en el sur de América del Sur.
- La región ha experimentado una significativa variabilidad natural de la temperatura en los últimos tres milenios.
- Las tendencias actuales de calentamiento, si las hay, en esta región no pueden atribuirse a causas antropogénicas basadas en los hallazgos de este estudio.
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