Human-caused Indo-Pacific warm pool expansion
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
The Indo-Pacific warm pool (IPWP) has warmed and grown substantially during the past century. The IPWP is Earth's largest region of warm sea surface temperatures (SSTs), has the highest rainfall, and is fundamental to global atmospheric circulation and hydrological cycle. The region has also experienced the world's highest rates of sea-level rise in recent decades, indicating large increases in ocean heat content and leading to substantial impacts on small island states in the region. Previous studies have considered mechanisms for the basin-scale ocean warming, but not the causes of the observed IPWP expansion, where expansion in the Indian Ocean has far exceeded that in the Pacific Ocean. We identify human and natural contributions to the observed IPWP changes since the 1950s by comparing observations with climate model simulations using an optimal fingerprinting technique. Greenhouse gas forcing is found to be the dominant cause of the observed increases in IPWP intensity and size, whereas natural fluctuations associated with the Pacific Decadal Oscillation have played a smaller yet significant role. Further, we show that the shape and impact of human-induced IPWP growth could be asymmetric between the Indian and Pacific basins, the causes of which remain uncertain. Human-induced changes in the IPWP have important implications for understanding and projecting related changes in monsoonal rainfall, and frequency or intensity of tropical storms, which have profound socioeconomic consequences.
Date Issued
2016-07
Date Acceptance
2016-06-03
Citation
Science Advances, 2016, 2 (7)
ISSN
2375-2548
Publisher
American Association for the Advancement of Science
Journal / Book Title
Science Advances
Volume
2
Issue
7
Copyright Statement
© 2016, The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/27419228
Subjects
Climate
El Nino-Southern Oscillation
Global Warming
Greenhouse Effect
Humans
Indian Ocean
Models, Theoretical
Pacific Ocean
Seawater
Temperature
climate models
greenhouse-gas forcing
Indo-Pacific warm pool
Pacific decadal oscillation
sea surface temperature
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2016-07-01