1. Drier tropical and subtropical Southern Hemisphere in the mid-Pliocene Warm Period.
- Author
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Pontes, Gabriel M., Wainer, Ilana, Taschetto, Andréa S., Sen Gupta, Alex, Abe-Ouchi, Ayako, Brady, Esther C., Chan, Wing-Le, Chandan, Deepak, Contoux, Camille, Feng, Ran, Hunter, Stephen J., Kame, Yoichi, Lohmann, Gerrit, Otto-Bliesner, Bette L., Peltier, W. Richard, Stepanek, Christian, Tindall, Julia, Tan, Ning, Zhang, Qiong, and Zhang, Zhongshi
- Subjects
RAINFALL ,PLIOCENE Epoch ,ATMOSPHERE ,METEOROLOGICAL precipitation - Abstract
Thermodynamic arguments imply that global mean rainfall increases in a warmer atmosphere; however, dynamical effects may result in more significant diversity of regional precipitation change. Here we investigate rainfall changes in the mid-Pliocene Warm Period (~ 3 Ma), a time when temperatures were 2–3ºC warmer than the pre-industrial era, using output from the Pliocene Model Intercomparison Projects phases 1 and 2 and sensitivity climate model experiments. In the Mid-Pliocene simulations, the higher rates of warming in the northern hemisphere create an interhemispheric temperature gradient that enhances the southward cross-equatorial energy flux by up to 48%. This intensified energy flux reorganizes the atmospheric circulation leading to a northward shift of the Inter-Tropical Convergence Zone and a weakened and poleward displaced Southern Hemisphere Subtropical Convergences Zones. These changes result in drier-than-normal Southern Hemisphere tropics and subtropics. The evaluation of the mid-Pliocene adds a constraint to possible future warmer scenarios associated with differing rates of warming between hemispheres. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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