What is a cloudburst? Why does it cause so much damage?
Though cloudbursts last only for a few minutes in a small area – usually not more than 80 sq km kilometres – it can cause flashfloods and landslides.india Updated: Aug 14, 2017 11:45 IST
Three people died as landslides, caused by a cloudburst, hit Uttarakhand’s district of Pithoragarh on Monday. A day before on Sunday, 46 people were killed after a landslide triggered by a cloudburst swept away several vehicles on a busy highway stretch in Himachal Pradesh.
What is a cloudburst?
The India Meteorological Department (IMD) labels sudden heavy downpour measuring over 100 mm per hour as cloudburst. Uttarakhand received 220 mm of rain during the 2013 cloudburst that killed more than 5,000 people.
Though they last for a few minutes in a small area – usually not more than 80 sq km kilometres – a cloudburst can cause flashfloods and landslides.
On an average, most places in India get around 20 mm of rain in 24 hours during the monsoons.
How does it happen?
Cloudbursts generally descend from very high vertically-formed clouds, sometimes extending 15 km up. The windward sides of mountains are conducive for generating thunderclouds with huge updrafts, which explains frequent cloudbursts in Ladakh, Uttarakhand and Himachal Pradesh.
Why does it cause so much damage?
Mountainous terrain adds momentum to large amounts of water gushing down, leading to landslides, mudslides and flooding.
Source: India Meteorological Department, Centre for Science and Environment
First Published: Aug 14, 2017 11:40 IST