Cyclone Nisarga | 02 Jun 2020

Why in News

A fast-moving depression in the Arabian Sea is predicted to be intensified into a severe cyclone named ‘Nisarga’.

Key Points

  • As per the India Meteorological Department, the impact of the cyclone is likely to be felt in Maharashtra and Gujarat.
  • There is a concern about the impact of the cyclonic storm on the battle against Covid-19, as the rain and flooding may set back social distancing and other necessary measures at evacuation centres, and even at some Covid-19 facilities located in low-lying areas.
  • Few days back, super cyclone Amphan - one of the strongest cyclones the country has seen in the last few decades - hit West Bengal, Odisha and Bangladesh.
    • Cyclone Nisarga is expected to be weaker than Cyclone Amphan in strength and intensity.
    • However in case of both the cyclones, the exceptional warm ocean temperatures seem to be behind the intense storms.
  • Cyclones in Arabian Sea:
    • While cyclones have always been more frequent in Bay of Bengal, they have been less frequent off of India’s western coast — a trend that has been gradually changing, according to scientists.
    • Further, cyclones formed in the Bay of Bengal are stronger than those on the Arabian Sea side. The relatively cold waters of the Arabian Sea discourage the kind of very strong cyclones that are formed on the Bay of Bengal side.
    • The year 2019 was slightly unusual as the Arabian Sea saw the most frequent and intense cyclonic activity in more than 100 years. Five cyclones originated in the area in 2019 — Vayu, Hikka, Kyarr, Maha and Pavan – when normally only one or two are formed.
      • The Arabian Sea saw more cyclonic storms than the Bay of Bengal during 2019. The Bay of Bengal reported less than normal number of cyclones. The three cyclones formed were — Cyclones Pabuk, Fani, Bulbul.
    • Post-monsoon cyclones have been seen in Arabian Sea. However, pre-monsoon cyclones, such as Nisarga, have so far been rare.

Tropical Cyclone

  • A Tropical cyclone is an intense circular storm that originates over warm tropical oceans and is characterized by low atmospheric pressure, high winds, and heavy rain.
  • A characteristic feature of tropical cyclones is the eye, a central region of clear skies, warm temperatures, and low atmospheric pressure.
  • Storms of this type are called hurricanes in the North Atlantic and eastern Pacific and typhoons in SouthEast Asia and China. They are called tropical cyclones in the southwest Pacific and Indian Ocean region.
  • In the southern hemisphere storms rotate clockwise and anticlockwise in the northern hemisphere.

India Meteorological Department

  • IMD was established in 1875.
  • It is an agency of the Ministry of Earth Sciences of the Government of India.
  • It is the principal agency responsible for meteorological observations, weather forecasting and seismology.

Source: IE