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Relación entre las tendencias a largo plazo de la composición isotópica de oxígeno-18 de la precipitación y el clima
Science (New York, N.Y.)
|November 6, 1992
Resumen
Las proporciones estables de isótopos en las precipitaciones son indicadores clave del paleoclima. Este estudio muestra la precipitación.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- La hidrología isotópica es la hidrología de isótopos.
- Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Las proporciones estables de isótopos de oxígeno (18O/16O) e hidrógeno (D/H) en el agua son indicadores cruciales del paleoclima.
- La interpretación cuantitativa de los datos paleoclimáticos está limitada por la comprensión incompleta del comportamiento global de los isótopos.
Objetivo del estudio:
- Para investigar la relación entre la composición isotópica de las precipitaciones y la temperatura del aire superficial.
- Para analizar las tendencias a largo plazo en la composición isotópica y la temperatura en las regiones de latitudes medias y altas.
Principales métodos:
- Análisis de los datos mensuales de precipitación y temperatura del aire superficial de la red "Isótopos en las precipitaciones" del OIEA-OMM.
- Análisis de series temporales del contenido de oxígeno-18 (delta 18O) y la temperatura en las últimas tres décadas.
Principales resultados:
- Los cambios a largo plazo en la composición isotópica de las precipitaciones siguieron de cerca los cambios en la temperatura del aire superficial.
- Se determinó un coeficiente de temperatura delta 18O promedio de aproximadamente 0,6 por mil por grado Celsius.
Conclusiones:
- La fuerte correlación apoya el uso de la composición isotópica de las precipitaciones como un indicador fiable del paleoclima.
- Proporciona una relación cuantitativa para reconstruir temperaturas pasadas a partir de registros de isótopos del paleoclima.
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