Context:
In recent years, many tornadoes have formed across India due to warming Bay of Bengal
Tornadoes:
- Tornadoes – Land-based vertical column of violently rotating air that extends from thunderstorm to ground.
- Origin –
- Tornado formation typically needs 4 ingredients: Shear, Lift, Instability, and Moisture.
- When there is wind shear, sometimes the winds begin to roll into a horizontal column of air.
- Once there is a strong updraft of air being transported from the ground to the atmosphere, that column of air becomes vertical. That is when a storm usually develops in this scenario.
- As the storm develops, it turns into a supercell thunderstorm. Supercells are storms that rotate and spin.
- With both the vertical, rotating column of air and the supercell thunderstorm together, that may bring down a tornado from the storm cloud.
- Seasonal variations – Most common in spring and least common in winter.
- Mostly occurred in – United States, Argentina and Bangladesh.
- Tornadoes in India – Reported in Eastern states of West Bengal, Odisha, and Jharkhand during pre-monsoon period.
- However, Tornadoes, unlike cyclones, have a relatively low frequency of occurrence in India.
Tropical Cyclones and Tornadoes:
Source: The Indian Express
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 10°C less than that of the surroundings.
Which of the statements given above is/are correct?
[UPSC Civil Service Exam – 2020 Prelims]
(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1 and 3 only
Answer: (c)
Explanation:
Statement 1 is incorrect. Jet streams occur both in the Northern Hemisphere as well as in the Southern Hemisphere.
Statement 3 is incorrect. The eye is the region of lowest surface pressure and warmest temperatures.