Can dust storms in Middle East alleviate drought in country?

MUMBAI: Dust storms originating from the Middle East and Northern Africa may be able to alleviate drought conditions over South Asia, including parts of India, suggests a new study by researchers at IIT-Bhubaneswar, published this month in the peer-reviewed journal Climate and Atmospheric Science, brought out by the Nature Group.

The study -- Arabian Sea Aerosol-Indian Summer Monsoon Rainfall relationship and its modulation by El-Nino Southern Oscillation -- demonstrates how aerosolised dust particles, which are transported above the Arabian Sea from the Middle East and surrounding areas during dust storms, can enhance rainfall over South Asia.

Researchers have also demonstrated that this phenomenon is likely to occur during severe drought episodes over the Indian region, which are observed alongside El-Nino climate events when warmer than usual waters in the equatorial region of the Pacific Ocean pull moistureladen clouds away from the Indian subcontinent.

This is made possible due to the warming induced by aerosolised dust over the Arabian Sea. When strong winds spread the dust over the ocean, it creates a heat trap, in turn, providing a vital source of energy that speeds up monsoon circulation of winds and moisture towards the Indian landmass.

“Our research has shown that this phenomenon occurs in a rather short time scale, of one or two weeks at most,” said V Vinoj, assistant professor at the School of Earth Ocean and Climate Sciences at IIT-Bhubaneswar.

Vinoj added that this phenomenon is particularly pronounced during drought years associated with El-Nino, and that tracking this correlation is an important step in understanding changing rainfall patterns over India.

“In response to anthropogenic climate change, El-Nino-like conditions are likely to increase in the future, making the dust aerosol-induced monsoon rainfall enhancement/modulation significant,” the study notes.

“This might not completely solve the issue of drought in India during El Nino events, but it can certainly help to alleviate the meteorological aspects of drought to some degree in the future,” Vinoj explained.