Context:
Cyclone Michaung made landfall in Andhra Pradesh.
About Cyclones:
- Cyclones are rapid inward air circulation around a low-pressure area.
- Classification –
- Tropical Cyclones: Originate between the Tropics of Capricorn and Cancer
- Extra Tropical/ Temperate Cyclones: Originate in the Polar Regions
Cyclone vs Anticyclone –
| Pressure System | Pressure Condition at the Centre | Pattern of Wind Direction | |
| Northern Hemisphere | Southern Hemisphere | ||
| Cyclone | Low | Anti-clockwise | Clockwise |
| Anti-cyclone | High | Clockwise | Anti-clockwise |
About Tropical Cyclones:
- An intense circular storm that originates over warm tropical oceans.
- Characteristic features –
- Eye, a central region of clear skies, warm temperatures, and low atmospheric pressure.
- Low atmospheric pressure, high winds, and heavy rain.
- Conditions for Formation –
- Large sea surface with temperature >27° C.
- Presence of the Coriolis force
- Small variations in the vertical wind speed
- A pre-existing weak low- pressure area
- Upper divergence above the sea level system
- Nomenclature –
- Nodal Authority – World Meteorological Organization (WMO)
- Indian Ocean Region – 13 member countries of WMO/ESCAP Panel on Tropical Cyclones (Bangladesh, India, Iran, Maldives, Myanmar, Oman, Pakistan, Qatar, Saudi Arabia, Sri Lanka, Thailand, United Arab Emirates and Yemen)
- Cyclones in India
- Bi-annual Cyclone Season – March to May and October to December
- Recent Cyclones –
- Arabian Sea: Biparjoy, Tauktae, Vayu, Nisarga and Mekanu
- Bay of Bengal: Mandous, Sitrang, Asani, Amphan, Fani, Nivar, Bulbul, Titli, Yaas
Different Names for Tropical Cyclones
- Typhoons – Southeast Asia and China
- Hurricanes – North Atlantic and eastern Pacific
- Tornados – West Africa and southern USA
- Willy-willies – Northwest Australia
- Tropical Cyclones – Southwest Pacific and Indian Ocean
Source: The Hindu
Previous Year Question
Consider the following statements:
1. Jet streams occur in the Northern Hemisphere only.
2. Only some cyclones develop an eye.
3. The temperature inside the eye of a cyclone is nearly 10ºC lesser than that of the surroundings.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2022 Prelims]
(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1 and 3 only
Answer: (c)
