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Title: Remote and local drivers of Pleistocene South Asian summer monsoon precipitation: A test for future predictions
South Asian precipitation amount and extreme variability are predicted to increase due to thermodynamic effects of increased 21st-century greenhouse gases, accompanied by an increased supply of moisture from the southern hemisphere Indian Ocean. We reconstructed South Asian summer monsoon precipitation and runoff into the Bay of Bengal to assess the extent to which these factors also operated in the Pleistocene, a time of large-scale natural changes in carbon dioxide and ice volume. South Asian precipitation and runoff are strongly coherent with, and lag, atmospheric carbon dioxide changes at Earth’s orbital eccentricity, obliquity, and precession bands and are closely tied to cross-equatorial wind strength at the precession band. We find that the projected monsoon response to ongoing, rapid high-latitude ice melt and rising carbon dioxide levels is fully consistent with dynamics of the past 0.9 million years.  more » « less
Award ID(s):
1634774 9986757 1755125
PAR ID:
10237349
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
7
Issue:
23
ISSN:
2375-2548
Page Range / eLocation ID:
eabg3848
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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