Related Topics

Fujiwhara Effect
2023 AUG   25
Semeru Volcano
2022 DEC   7
Sixth mass extinction
2022 JAN   27
Solar flares
2022 JAN   24
Ring of fire region
2020 DEC   1

Cloudbursts

2021 AUG 6

Preliminary   > Geography   >   Geophysical phenomenon   >   Geophysical phenomenon

Why in news?

  • Increasing incidents of cloudbursts in Jammu and Kashmir, Himachal Pradesh and Uttarakhand are a clear evidence of climate change, experts have pointed out.

What is cloudbursts?

  • A cloudburst is an intense torrential rainfall that lasts for a relatively short duration (few minutes to few hours).
  • It is accompanied by hail and thunder, which is capable of creating flash floods.
  • Every intense rainfall is not a cloudburst. It is a cloudburst when the amount of rainfall in a particular region exceeds 100 millimetres per hour, according to IMD
  • At least 26 cloudbursts occurred in the Himalayan region from January through July 29, 2021

Why does cloudburst occur?

  • Cloudburst occurs when moisture-rich air travels up a mountainous region, forming a vertical column of clouds known as Cumulonimbus clouds.
  • These clouds usually cause rain, thunder and lightning. This upward movement of clouds is also known as ‘orographic lift’. Due to these unstable clouds, heavy rainfall may occur over a small area.
  • The upward movement of clouds provides the required energy for a cloudburst.
  • It usually happens at 1,000-2,500 metres above the sea level. The moisture is usually provided by low-level eastern winds associated with a low-pressure system over the Gangetic plains.

Cloud bursts in Himalayas:

  • Oceans are warming up fast, as a result of which moisture-rich air reaches the Himalayan region. This leads to cloudburst.
  • It is likely to occur more with an increase in moisture from the Indian Ocean

PRELIMS QUESTION

Consider the following statements regarding ‘cloudbursts’:

1. According to India Meteorological Department, a rainfall can be considered a cloudburst only if the amount of rainfall in a particular region exceeds 100 millimetres per hour

2. Cloudbursts in the Himalayan region usually happen in July and August.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Answer