Indo-Pacific Warm Pool Will Envelope Eighty Percent of the Tropical Indian Ocean by 2070
Abstract
The observed warming trends in the Indian Ocean (IO) Sea Surface Temperature (SST) have impacted the lives and livelihoods of about one-third of the world's population neighboring the IO and the rest of the world. The observed IO Warm Pool (IOWP) the region where SST exceeds 28 oC - and its counterpart in the western Pacific Ocean have also been expanding non-linearly. The SST warming signal in IO, having the highest rates among the tropical ocean basins, is a conglomeration of anthropogenic and natural climate variations; their separation via statistical analyses is challenging. The Spatio-temporal characteristics of the observed warming of IO SST and its statistical link to the IOWP are still unclear. This study discriminates the basin-wide monotonic warming mode of the IO surface from the internally and remotely forced variability. Instead of the structure-less trend patterns reported earlier, the radically different warming signal shows that the monotonic warming in observed IO SST has the spatial pattern of summer-mean SST and the Warm Pool as its most conspicuous feature. The highest warming is (0.17 oC per decade) in the IOWP and not in the other IO regions identified in previous studies. By 2070, the IOWP will cover about 80 percent of tropical IO at the present latitudinal expansion rates. The mean states of SST, wind, and surface pressure are shifting the IO climate towards an endless summer. Irrespective of the season, the SST near Indonesia will likely remain above 31 oC by 2080 and beyond; this would substantially increase local rainfall intensity and frequency.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.A25U..03K