Climate change to almost triple risk of extreme Indian Ocean weather events
Shifting climate patterns in the Indian Ocean, driven by global warming, are likely to increase the frequency of “devastating” weather events for much of Australia, Indonesia and eastern Africa, a study led by Australian researchers has found.
Countries around the Indonesian archipelago have been advised to brace for more devastating events that could bring more and severe drought, bushfires and floods to affected countries.
While most of the attention has so far been focused on the prospect of an El Nino forming over the Pacific Ocean, a similar phenomenon may be under way in the Indian Ocean that could exacerbate dry and hot conditions for large areas of Australia. Tropical sea-surface temperatures in the eastern Indian Ocean are becoming cool relative to those in the west. This happened in 1997 when surface waters off the coast of Indonesia cooled and the ocean’s predominant westerly winds reversed, leading to catastrophic weather. Fires raged across a drought-stricken Indonesia, and floods across east African nations killed thousands.
Known as a positive-Indian Ocean Dipole (IOD), such conditions typically mean less convection off north-western Australia and reduced rainfall in winter and spring for south-eastern and central Australia. Indonesia also tends to endure drought and bushfires while east Africa gets hit by floods.
While climate models will need another month or two to be certain about an El Nino and a positive-IOD, the long-term outlook projects increased frequency of extremes of both phenomena.
The study, published in journal Nature on Thursday, also suggests that climate change could make years like 1997 happen more often and positive-IODs will almost triple from one every 17.3 years over the 20th century to one every 6.3 years this century.
While India, Indonesia and Australia continue to face extreme weather events, Africa has increasingly been gaining attention as a prospective victim of climate change. Earlier this month, a group of scientists in Germany claimed to have identified for the first time the "hot spots of climate change” in Africa.
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