The ‘flying rivers’ causing devastating floods in India

Meteorologists in other regions have been able to link a few recent major floods to atmospheric rivers.

In April 2023, Iraq, Iran, Kuwait and Jordan were all hit by catastrophic flooding after intense thunder, hailstorms and exceptional rainfall. Meteorologists later found that the skies across the region were carrying a record amount of moisture, surpassing a similar event in 2005.

Two months later, Chile was hit by 500mm of rain in just three days – the sky dumped so much water that it also melted snow on some parts of the Andes mountain, unleashing massive floods that destroyed roads, bridges, and water supplies.

A year earlier parts of Australia had been hit by what politicians called a “rain-bomb”, with more than 20 people killed and thousands evacuated.

Given the risks of catastrophic floods and landslides they can trigger, atmospheric rivers have been categorised into five types based on their size and strength – just like hurricanes.

Not all of them are damaging though, especially if they are of low intensity.

Some can be beneficial if they land in places that have suffered from prolonged droughts.

But the phenomenon is an important reminder of a rapidly warming atmosphere that holds much more moisture than in the past.

At the moment, the storm is relatively under-studied in South Asia, compared to other weather events like western disturbances or Indian cyclones that are the other major causes of floods and landslides.

“Effective collaborative efforts among meteorologists, hydrologists and climate scientists is currently challenging as the concept is new in this region and difficult to introduce,” said Rosa V Lyngwa, a research scholar at IIT Indore.

But as heavy rains continue to pummel parts of India, it’s become more important to study this storm and its potential devastating impact, she adds.