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conferenceseries
.com
Volume 8, Issue 10 (Suppl)
J Earth Sci Clim Change, an open access
ISSN: 2157-7617
Climate Change 2017
October 19-21, 2017
CLIMATE CHANGE
October 19-21, 2017 | Rome, Italy
4
th
World Conference on
The future of subtropical rainfall
Jie He
Princeton University, USA
T
he subtropics encompass many of the world’s driest regions and climate models robustly predict a large-scale decline in
subtropical precipitation from anthropogenic forcing. This projection has become popularly related to the dry-get-drier
paradigm. The expectation that climate change will generally exacerbate the rainfall deficiency of the subtropical regions has
excited great concerns. On the other hand, some studies have attributed the subtropical precipitation decline to the pole ward
expansion of the Hadley cell. In this talk, I will show that neither the dry-get-drier nor pole ward expansion mechanism is
relevant to the large-scale subtropical precipitation decline. It is found that the subtropical precipitation decline forms primarily
from the fast adjustment to CO
2
forcing in which neither of the two proposed mechanisms exists. Permitting the increase
in moisture and the Hadley cell expansion does not substantially change the characteristics of the large-scale subtropical
precipitation decline. This precipitation change should be interpreted as a response to the land-sea warming contrast, direct
radiative forcing of CO
2
and in certain regions, pattern of SST changes. In addition, a careful examination of the spatial patterns
of the projected precipitation change shows that the subtropical precipitation decline is primarily located over ocean. Over
subtropical land regions, the precipitation decline is muted or even reversed by the land-sea warming contrast.
Biography
Jie He has studied changes in hydro-climate and atmospheric circulation from anthropogenic forcing. His research focuses on understanding the physical
mechanisms of the climate system using model simulations. His presentation is about the subtropical precipitation has recently been published in
Nature Climate
Change
. He has also worked on understanding and reducing uncertainties in climate projections on both global and regional scales. One of his current research
projects involves the dynamics of tropical air-sea interactions. The goal is to quantify various coupling feedback processes in order to build a simple and practical
framework for understanding model biases and future changes in air-sea interaction. He has also started working on the connection between transient climate
sensitivity and regional ocean heat uptake.
jie.he@noaa.govJie He, J Earth Sci Clim Change 2017, 8:10(Suppl)
DOI: 10.4172/2157-7617-C1-036