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Temperatura y elevación de la superficie antártica durante el último máximo glacial
Christo Buizert1, T J Fudge2, William H G Roberts3
1College of Earth Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA. christo.buizert@oregonstate.edu.
Science (New York, N.Y.)
|June 4, 2021
Resumen
Este estudio revela el enfriamiento del Último Máximo Glacial en la Antártida, con un enfriamiento de la Antártida Occidental de 10 ° C y la Antártida Oriental de 4-7 ° C. Estos hallazgos concilian los datos paleoclimáticos con los modelos climáticos.
Área de la Ciencia:
- Paleoclimatología
- Glaciología
- Investigaciones en la Antártida
Sus antecedentes:
- Los isótopos estables al agua en los núcleos de hielo polar son un indicador clave de la temperatura.
- La calibración de estos proxies es un desafío, especialmente en la Antártida Oriental.
- Comprender el clima antártico pasado es crucial para predecir el cambio climático futuro.
Objetivo del estudio:
- Para reconstruir la magnitud y el patrón espacial del enfriamiento de la superficie del último máximo glacial en la Antártida.
- Para comparar los datos del núcleo de hielo con los resultados del modelo climático global.
- Para conciliar las discrepancias entre las diferentes reconstrucciones proxy paleoclimáticas.
Principales métodos:
- Análisis de la termometría de pozos y las propiedades de firn de siete núcleos de hielo antárticos.
- Incorporación de datos sobre el contenido de aire de los núcleos de hielo para tener en cuenta los cambios topográficos.
- Comparación de las temperaturas reconstruidas con datos proxy de isótopos de agua y simulaciones de modelos climáticos.
Principales resultados:
- Los sitios de la Antártida Occidental experimentaron un enfriamiento de la superficie de aproximadamente 10 ° C en relación con el período preindustrial.
- Los sitios de la Antártida Oriental mostraron un rango de enfriamiento de aproximadamente 4 ° C a 7 ° C.
- El enfriamiento reconstruido en la Antártida Oriental se alinea con los modelos climáticos cuando se consideran los cambios topográficos, pero es menor que las estimaciones de los proxies de isótopos de agua calibrados contra los gradientes modernos.
Conclusiones:
- El estudio proporciona una estimación refinada del enfriamiento del Último Máximo Glacial en la Antártida.
- Una inversión alterada de la temperatura antártica durante el período glacial ayuda a conciliar los nuevos hallazgos con las observaciones de isótopos de agua.
- Esta investigación mejora la fiabilidad de las reconstrucciones paleoclimáticas en la Antártida.
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