Global Warming Slowdown Tracked to Indian Ocean
Global surface warming has slowed since the start of the twenty-first century, while Pacific heat uptake was enhanced. Analyses of ocean heat content suggest that the warm water was transferred to the Indian Ocean, through the Indonesian straits, reports "Natue".
Scientists reported that the Indian Ocean heat content has risen sharply, accounting for more than 70% of the global ocean heat gain in the upper 700 metres of the Indian Ocean over the past decade.
The scientists conclude the Indian Ocean has become increasingly important in altering global climate variability.
A team led by University of Miami and National Oceanic and Atmospheric Administration (NOAA) researcher Sang-Ki Lee experimented with a global climate model. A computer modeling study by them points to strong easterly trade winds that caused warm water to pile up in the western Pacific and seep into the Indian Ocean, which may now hold more than 70% of the heat absorbed by the upper ocean in the past decade.
Until now, climate scientists believed the slowdown, which has been observed since 1998, was related to declines in surface temperature of Pacific Ocean, and tied to a prevalence of La Nina climate conditions.
“We find that the enhanced heat uptake by the Pacific Ocean has been compensated by an increased heat transport from the Pacific Ocean to the Indian Ocean, carried by the Indonesian throughflow,”a paper published in the Nature Geoscience Journal on Tuesday said.
A team of scientists from both the US and the German GEOMAR Helmholtz Centre for Ocean Research Kiel have demonstrated that the heat content of the Indian Ocean has risen substantially since the late 1990s, even though the global temperature showed only minor changes in the same period.
This increase is very likely caused by a higher heat transfer from the Pacific to the Indian Ocean, as the authors report in the international scientific journal Nature Geoscience.
