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La variabilidad climática del Holoceno a escala centenaria revelada por un registro de alta resolución del
F McDermott1, D P Mattey, C Hawkesworth
1Department of Geology, University College Dublin, Dublin 4, Ireland.
Science (New York, N.Y.)
|November 10, 2001
Resumen
La variabilidad climática del Holoceno en los núcleos de hielo de Groenlandia es clave para comprender el calentamiento futuro. Un registro de espeleotemas de Irlanda muestra coherencia climática regional, revelando eventos de enfriamiento del Holoceno temprano.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- La geoquímica de los isótopos es la geoquímica de los isótopos.
- Ciencia Cuaternaria La ciencia cuaternaria es la ciencia cuaternaria.
Sus antecedentes:
- Comprender la variabilidad climática del Holoceno es esencial para predecir los impactos futuros del calentamiento antropogénico.
- Los núcleos de hielo de Groenlandia proporcionan archivos paleoclimáticos críticos y de alta resolución.
- Las fluctuaciones del isótopo de oxígeno (delta18O) en núcleos de hielo a escala submilenial reflejan las dinámicas climáticas pasadas.
Objetivo del estudio:
- Para evaluar la importancia de la variabilidad del delta18O submillennial del Holoceno en los núcleos de hielo de Groenlandia.
- Investigar la coherencia climática regional comparando los registros de espeleotemas irlandeses con los datos de núcleos de hielo de Groenlandia.
- Identificar posibles eventos de enfriamiento del Holoceno temprano y evaluar los impactos del rafting sobre el hielo del Atlántico Norte.
Principales métodos:
- Análisis de isótopos de oxígeno (delta18O) de alta resolución de un espeleotema del suroeste de Irlanda.
- Correlación de los registros de espeleotemas delta18O con los datos existentes del núcleo de hielo de Groenlandia delta18O.
- Análisis de las variaciones climáticas a escala centenaria y evidencia de rafting en hielo.
Principales resultados:
- Las variaciones del delta18O de Speleothem se correlacionan con los cambios del delta18O del núcleo de hielo de Groenlandia, lo que indica una coherencia climática regional del Holoceno temprano.
- Se identificaron pruebas de eventos de enfriamiento del Holoceno temprano no detectados anteriormente.
- El rafting de hielo en el Atlántico Norte de mediados a finales del Holoceno tuvo un impacto mínimo en el registro delta18O del espeleotema irlandés.
Conclusiones:
- Los registros de Speleothem ofrecen información valiosa sobre las dinámicas climáticas regionales que complementan los datos de núcleos de hielo.
- El clima del Holoceno temprano exhibió una significativa variabilidad a escala centenaria y una coherencia regional.
- Los sitios de margen oceánico pueden mostrar respuestas amortiguadas a los eventos de rafting de hielo en el Atlántico Norte en comparación con los registros de núcleos de hielo.
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