Similar patterns of tropical precipitation and circulation changes under solar and greenhouse gas forcing
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Theory and model evidence indicate a higher global hydrological sensitivity for the same amount of surface warming to solar as to greenhouse gas (GHG) forcing, but regional patterns are highly uncertain due to their dependence on circulation and dynamics. We analyse a multi-model ensemble of idealized experiments and a set of simulations of the last millennium and we demonstrate similar global signatures and patterns of forced response in the tropical Pacific, of higher sensitivity for the solar forcing. In the idealized simulations, both solar and GHG forcing warm the equatorial Pacific, enhance precipitation in the central Pacific, and weaken and shift the Walker circulation eastward. Centennial variations in the solar forcing over the last millennium cause similar patterns of enhanced equatorial precipitation and slowdown of the Walker circulation in response to periods with stronger solar forcing. Similar forced patterns albeit of considerably weaker magnitude are identified for variations in GHG concentrations over the 20th century, with the lower sensitivity explained by fast atmospheric adjustments. These findings differ from previous studies that have typically suggested divergent responses in tropical precipitation and circulation between the solar and GHG forcings. We conclude that tropical Walker circulation and precipitation might be more susceptible to solar variability rather than GHG variations during the last-millennium, assuming comparable global mean surface temperature changes.
Date Issued
2021-10-01
Date Acceptance
2021-09-21
Citation
Environmental Research Letters, 2021, 16 (10), pp.1-10
ISSN
1748-9326
Publisher
Institute of Physics (IoP)
Start Page
1
End Page
10
Journal / Book Title
Environmental Research Letters
Volume
16
Issue
10
Copyright Statement
© 2021 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000706847600001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Life Sciences & Biomedicine
Physical Sciences
Environmental Sciences
Meteorology & Atmospheric Sciences
Environmental Sciences & Ecology
solar forcing
GHG forcing
PDRMIP
CESM last millennium
STRATOSPHERIC OZONE
CLIMATE
PACIFIC
RESPONSES
OCEAN
SIMULATIONS
REDUCTION
CYCLE
SLOW
Publication Status
Published
Article Number
ARTN 104045
Date Publish Online
2021-10-12