Abstract
The Hadley circulation (HC) extent and strength are analyzed in a wide range of simulated climates from the Last Glacial Maximum to global warming scenarios. Motivated by HC theories, we analyze how the HC is influenced by the subtropical stability, the near-surface meridional potential temperature gradient, and the tropical tropopause level. The subtropical static stability accounts for the bulk of the HC changes across the simulations. However, since it correlates strongly with global mean surface temperature, most HC changes can be attributed to global mean surface temperature changes. The HC widens as the climate warms, and it also weakens, but only robustly so in the Northern Hemisphere. On the other hand, the Southern Hemisphere strength response is uncertain, in part because subtropical static stability changes counteract meridional potential temperature gradient changes to various degrees in different models, with no consensus on the response of the latter to global warming.
Original language | American English |
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Pages (from-to) | 8585-8591 |
Number of pages | 7 |
Journal | Geophysical Research Letters |
Volume | 44 |
Issue number | 16 |
DOIs | |
State | Published - 28 Aug 2017 |
Bibliographical note
Funding Information:This study has been funded by University of Salento, joined by CMCC within the PhD school in Ecology and Climate Change and by the JPI Climate-Belmont Forum project “PaCMEDy” (http://www.jpi-climate.eu/ 2015projects/pacmedy). The CMIP5 and PMIP3 data have been analyzed using GOAT (Geophysical Observations Analysis Tool, www.goat-geo.org).
Publisher Copyright:
©2017. American Geophysical Union. All Rights Reserved.
Keywords
- Hadley circulation
- PMIP3-CMIP5 climate models
- climate change