Context

• On July 28, at least seven people were killed, 17 injured and over 35 missing after a cloudburst hit a remote village of Jammu and Kashmir.

What is a cloudburst?

• Cloudbursts are short-duration, intense rainfall events over a small area.
• According to the India Meteorological Department (IMD), it is a weather phenomenon with unexpected precipitation exceeding 100mm/h over a geographical region of approximately 20-30 square km.

Occurrence

• Cloudburst is basically a rainstorm and occurs mostly in the desert and mountainous regions, and in interior regions of continental landmasses due to the warm air current from the ground or below the clouds rushes up and carries the falling raindrops up with it.
• The rain fails to fall down in a steady shower, which causes excessive condensation in the clouds as new drops form and old drops are pushed back into it by the updraft.

Meteorological Factors behind the Cloudburst

• Atmospheric pressure, atmospheric temperature, rainfall, cloud water content, cloud fraction, cloud particle radius, cloud mixing ratio, total cloud cover, wind speed, wind direction, and relative humidity during the cloudburst, before as well as after the cloudburst.
• Relative humidity and cloud cover is at the maximum level with low temperature and slow winds.

Findings

• Several studies have shown that climate change will increase the frequency and intensity of cloudbursts in many cities across the globe.
• World Meteorological Organization noted that there is about a 40% chance of the annual average global temperature temporarily reaching 1.5°C above the pre-industrial level in at least one of the next five years.
• It added that there is a 90% likelihood of at least one year between 2021 and 2025 becoming the warmest on record and dislodge 2016 from the top rank.
• As temperatures increase the atmosphere can hold more and more moisture and this moisture comes down as a short very intense rainfall for a short duration probably half an hour or one hour resulting in flash floods in the mountainous areas and urban floods in the cities.
• Also, there is evidence suggesting that globally short duration rainfall extremes are going to become more intense and frequent.
• With warming climate or climate change, we will witness these cloudburst events in increased frequency in the future.

https://indianexpress.com/article/explained/explained-cloudbursts-frequent-jk-uttarakhand-himachal-pradesh-imd-7428954/

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