Why recent extreme rain events in Hyderabad?

New study throws fresh light, linking moisture transport from Arabian Sea in summer to heavy rain.

By Author  |  Published: 12th Oct 2017  12:05 amUpdated: 11th Oct 2017  11:33 pm
Hyderabad Rains

Hyderabad: Ever wondered why Hyderabad in the last few years has been at the receiving end of extreme rain events. Instances like parts of the city receiving heavy rainfall within a few hours, inundating the entire region and making it difficult for everybody, including the municipal officials, to recover have become all too common.

While there could be a host of climatic conditions, including cyclones and local weather conditions, that often cause such extreme rain events, a new study by Indian researchers has thrown fresh light on the issue.

According to researchers, Hyderabad and other parts of Telangana fall in the region of the country that has witnessed a three-fold increase in extreme rain events between 1950 and 2015.

The multi-centric study conducted by researchers reveals that moisture transport from the Arabian Sea during the summer monsoon months between April and September is a major contributor for the build-up of such extreme rain events over central parts of India.

Trigger for rain

“There are occasions when winds are carrying huge amounts of moisture from the Arabian Sea and dumping all across Central India, including Maharashtra, Telangana, parts of Odisha and up to Assam, triggering such events,” says researcher, Centre for Climate Change Research, Indian Institute of Tropical Meteorology (IITM), Pune, Dr. Roxy Mathew Koll.

Interacting with Telangana Today, the researcher who was the lead in the study, said that instances of extreme rainfalls events in urban areas in October, when the winter monsoons are active, could be attributed to global warming and land use pattern in urban cities.

“Temperatures are rising everywhere and in warm conditions, the air can hold more moisture for a longer period of time. Then there is the issue of land use patterns, which is dominated by concrete these days. When air holds a lot of moisture, then the rains are heavy,” analyses Dr. Roxy.

The study, in which researchers from IIT, Bombay and Ministry of Earth Sciences participated, also says that the over the last decade the mean monsoon level in the central region has decreased. And yet, due to the moisture being carried from Arabian Sea, extreme rain events are on the rise at a rate of 13 such events for a decade.