Hemispheric climate shifts driven by anthropogenic aerosol-cloud interactions

Eui Seok Chung, Brian J Soden

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

The contrasting rainfall between the wet tropics and the dry subtropics largely determines the climate of the tropical zones. A southward shift of these rain belts has been observed throughout the latter half of the twentieth century, with profound societal consequences. Although such large-scale shifts in rainfall have been linked to interhemispheric temperature gradients from anthropogenic aerosols, a complete understanding of this mechanism has been hindered by the lack of explicit information on aerosol radiative effects. Here we quantify the relative contributions of radiative forcing from anthropogenic aerosols to the interhemispheric asymmetry in temperature and precipitation change for climate change simulations.We show that in model simulations the vast majority of the precipitation shift does not result from aerosols directly through their absorption and scattering of radiation, but rather indirectly through their modification of cloud radiative properties. Models with larger cloud responses to aerosol forcing are found to better reproduce the observed interhemispheric temperature changes and tropical rain belt shifts over the twentieth century, suggesting that aerosol-cloud interactions will play a key role in determining future interhemispheric shifts in climate.

Original languageEnglish (US)
Pages (from-to)566-571
Number of pages6
JournalNature Geoscience
Volume10
Issue number8
DOIs
StatePublished - Aug 1 2017

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volcanic cloud
aerosol
climate
twentieth century
rainfall
radiative forcing
temperature gradient
simulation
asymmetry
temperature
scattering
climate change

ASJC Scopus subject areas

  • Earth and Planetary Sciences(all)

Cite this

Hemispheric climate shifts driven by anthropogenic aerosol-cloud interactions. / Chung, Eui Seok; Soden, Brian J.

In: Nature Geoscience, Vol. 10, No. 8, 01.08.2017, p. 566-571.

Research output: Contribution to journalArticle

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