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Title: The Influence of Volcanic Aerosol Meridional Structure on Monsoon Responses over the Last Millennium
Abstract

Monsoon responses to eruptions over the last millennium (LM) are examined in an ensemble of climate simulations as a function of eruption hemisphere. A composite analysis reveals a particularly strong sensitivity of monsoon rainfall in the year following Northern Hemisphere (NH) extratropical eruptions. Additional analysis focusing on the 18th century eruption of Mt. Laki and idealized simulations representing an analogue Southern Hemisphere eruption (SH‐Laki) reveal monsoon responses that are approximately symmetric across hemispheres, despite exhibiting asymmetries in other aspects of the climate response. We conclude that 1) latitudinally mirrored eruptions result in approximately symmetric monsoon responses, 2) disproportionate weakening (strengthening) of NH (SH) monsoons by NH eruptions over the LM resulted in part from their relatively high latitudes, and 3) uncertainty in eruption latitude fundamentally limits our ability to accurately simulate associated monsoon and tropical precipitation responses in nature.

 
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Award ID(s):
1805143
NSF-PAR ID:
10372440
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
46
Issue:
21
ISSN:
0094-8276
Page Range / eLocation ID:
p. 12350-12359
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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