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La temperatura de la superficie del mar a partir de las proporciones de estroncio/calcio en el esqueleto de coral
Science (New York, N.Y.)
|July 31, 1992
Resumen
Las proporciones de estroncio/calcio de los corales revelan temperaturas pasadas de la superficie del mar tropical (SST). Este método reconstruye con precisión la SST histórica, mostrando climas tropicales más fríos y más variables durante la deglaciación.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- La geoquímica es la geoquímica.
- Oceanografía La oceanografía es la oceanografía.
Sus antecedentes:
- Comprender la variabilidad del clima tropical en el pasado es crucial para predecir el cambio climático futuro.
- Los esqueletos de coral preservan los proxies geoquímicos que registran las condiciones ambientales.
Objetivo del estudio:
- Para reconstruir temperaturas pasadas de la superficie del mar tropical (SST) utilizando la geoquímica de los corales.
- Investigar los cambios en la SST y la estacionalidad durante la última deglaciación.
Principales métodos:
- Mediciones de alta precisión de las relaciones estroncio/calcio de los corales utilizando espectrometría de masas de ionización térmica.
- Calibración de la relación SST-proxy utilizando corales modernos y termometría de isótopos de oxígeno.
- Análisis de un coral fósil para determinar el pasado SST y las variaciones estacionales.
Principales resultados:
- Reconstruido SST con una precisión aparente mejor que 0,5 grados C.
- Los datos de los corales fósiles indican que las SST anuales promedio eran aproximadamente 5 grados C más frías hace 10.200 años cerca de Vanuatu.
- Las variaciones estacionales de SST fueron mayores en el pasado en comparación con las condiciones actuales.
Conclusiones:
- Las relaciones Sr/Ca de los corales proporcionan un indicador fiable para la reconstrucción de las SST tropicales en escalas de tiempo milenarias.
- Las zonas de clima tropical fueron comprimidas hacia el ecuador durante el período de deglaciación.
- Las reconstrucciones climáticas pasadas ofrecen información sobre la sensibilidad de las regiones tropicales a los cambios climáticos globales.
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