Australia's Bushfires, Droughts Blamed on Indian Ocean Phenomenon

Extreme weather events in Australia like droughts and bushfires are caused by changes in temperature in the Indian Ocean. In a study released on Nov. 29 and published on Nature Geoscience, the Indian Ocean Dipole (IOD) has significant consequences like the El Nino phenomenon in the Pacific Ocean. The temperature changes in the Indian Ocean will more likely to intensify due to the effects of climate change.

The Indian Ocean phenomenon is a result of the interaction between the ocean and the atmosphere. The IOD usually develops in the Southern Hemisphere during winter and becomes ready in spring. Ocean temperatures off the coast of Java and Sumatra re lower than usual while temperatures near the equator become warmer. The changes in temperature have significant effects in the atmosphere.

The Indian Ocean Dipole can cause extreme weather in various parts of the world including great floods in East African nations and severe droughts in Indonesia. The recent study links the same phenomenon with the bushfires in Australia.

The southeast part of Australia will experience a low amount of rainfall and high temperatures during a positive IOD event. Most of the rainfall in southeast Australia during the winter and spring come from the tropical eastern part of the Indian Ocean.

Scientists have shown in earlier studies that the Indian Ocean phenomenon is linked to extreme weather events in Australia. In the new study, researchers have shown that the link is not merely a statistical fluke and extreme weather can be simulated by climate models.

Upward trend to continue

The scientists linking the Indian Ocean to extreme weather in Australia have analysed 54 climate models and experiments used in the International Panel on Climate Change (IPCC) Fifth Assessment Report. According to scientific data, IOD index is on an upward trend. Climate models have indicated that the trend will continue to rise in the next hundred years.

A continuous drying trend will continue to affect south east Australia. The slow warming trend can lead to frequent Indian Ocean Dipole events and the dry conditions will intensity compared to existing climate. Scientists said that rainfall in Australia will become less frequent.

The major bushfires in NSW in the last few weeks have been associated with positive IOD events in the spring and winter. The IOD can be used to predict the possibility of bushfires during the summer and anticipate risk.