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| Titel |
Impacts of polar ice sheets on the East Asian monsoon during the MIS-13 interglacial |
| VerfasserIn |
Feng Shi, Qiuzhen Yin, Irina Nikolova, Zhengtang Guo, Andre Berger |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250142685
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| Publikation (Nr.) |
 EGU/EGU2017-6332.pdf |
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| Zusammenfassung |
| Among all the interglacials of the last one million years, Marine Isotope Stage (MIS) 13 has
the highest δ18O value over the past 800 ka in the deep-sea sediments. This would indicate
that MIS-13 is the coolest interglacial if assuming δ18O mainly represents global ice volume.
The Antarctic ice core records show also that MIS-13 is the coolest interglacial over
Antarctica with almost the lowest greenhouse gases concentrations (GHG). However, many
proxy records from the northern hemisphere (NH) indicate that MIS-13 is at least as warm
as or even warmer than the recent interglacials, with extremely strong summer
monsoon and a possible melting of Greenland ice sheet. In this study, based on
proxy reconstructions, different scenarios regarding the size of the Greenland and
Antarctic ice sheets are made, and the response of the East Asian summer monsoon to
these scenarios are tested by using the models HadCM3 and LOVECLIM as well as
factor separation analysis and under the astronomical and GHG configurations of
MIS-13. The results show that the influence of the disappearance of Greenland
ice sheet on the surface temperature is quite localized, mainly over the northern
high latitudinal regions, however, the influence of the bigger southern Hemisphere
(SH) ice sheet on the surface temperature is very global, especially in the southern
hemisphere. This ice sheet condition has an impact on the precipitation pattern over
tropical-subtropical regions. It causes much more summer precipitation over all the East
Asian monsoon region, in consistent with the paleosol record from southern China. The
scenario of melted Greenland ice sheet and of larger SH ice sheets provides one of
the explanations of the strong monsoon rainfall documented by the proxy data. |
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