Question – Highlight India’s sensitivity to ‘cloud burst’. What measures have been adopted to manage these incidents? – 24 February 2022
Answer – A cloud burst is an event of intense rainfall of short duration over a small area. It is a seasonal phenomenon with unpredictable rainfall in excess of 100 mm/h, over a geographical area of about 20-30 square Km. In the Indian subcontinent, this phenomenon usually occurs when the monsoon moves northwards, from the Bay of Bengal or the Arabian Sea to the plains and then towards the Himalayas, sometimes producing 75 mm of rainfall per hour.
Relative humidity and cloud cover are at peak levels with low temperatures and slow winds, causing clouds to condense at high speeds, and may result in cloudbursts.
As the temperature rises, the atmosphere can hold more and more moisture and this moisture causes very intense rainfall over a short period (perhaps for half an hour or an hour) resulting in flash floods in mountainous areas and Urban floods occur in cities.
Extent of India’s vulnerability:
- The Himalayan region, especially the Western Himalayas, is considered the most vulnerable to cloudbursts, as it provides suitable conditions for cloudbursts.
- The orography of the Himalayas with its steep and unstable slopes makes it an ideal platform for the occurrence of such cloud bursts, which can lead to flash floods or landslides.
- Most of the damages to properties, communication system and human casualties are as a result of flash floods. The phenomenon occurs due to sudden upward drift of moisture-laden clouds as a tall vertical column termed “Cumulonimbus Clouds” usually associated with cloudbursts.
Measures to deal with ‘Cloudburst’:
- Formation of land use model on the basis of vulnerability profile, haphazard construction of buildings on unsafe slopes in mountains is avoided.
- Efforts have been made to free the catchment areas and wetlands which also act as sponge system from all encroachments.
- One should try to undertake afforestation programs to cover all types of fractured topography to prevent flash floods that occur after cloudbursts.
- Sensors have been installed to collect and process data related to rainfall patterns. These data are then analyzed and warnings are issued in case cloudburst events are predicted.
- The government plans to have a sensor-based prediction system in pockets likely to cloudbursts. This will provide some important opportunities for relief and rescue operations.
In short, cloudburst is difficult to predict, although India can learn from Denmark which has taken a lead in post-cloud management. Although the ‘NAPCC of the Himalayan Ecosystem Framework’ deals with sustainable habitats, much more remains to be done to prevent the loss of life and property in these vulnerable locations.
