North-East Monsoon Ends with 30% Surplus Rain | 03 Jan 2020
Why in News
India witnessed a 30% surplus in total rainfall during the Northeast monsoon in 2019.
- October to December is recognised as the period for Northeast monsoon by the India Meteorological Department (IMD).
Key Points
- In 2019, the Southwest monsoon withdrew late so there was a delay for the onset of the northeast monsoon. Despite this, southern peninsula received normal or above-normal rainfall during the three months.
- Rainfall during these three months was evenly distributed, both spatially and temporally, with every week recording normal rainfall throughout the season.
- 2019 witnessed the rare meteorological coincidence of the northeast monsoon making its onset on the same day as the southwest monsoon withdrew officially.
Two Monsoons of India
- The south-west monsoon (summer monsoon) blows from sea to land after crossing the Indian Ocean, Arabian Sea, and the Bay of Bengal.
- It brings most of the rainfall in the country, approximately 75% of India’s annual rainfall.
- It gets its name from the direction in which it travels, from the southwest to the northeast.
- The northeast monsoon (winter monsoon) blows from land to sea.
- During this period, rainfall is experienced over southern states, mainly Tamil Nadu, Kerala, Andhra Pradesh along with some parts of Telangana and Karnataka.
- In areas around Jammu and Kashmir, Himachal Pradesh, Uttarakhand and along the northeast, precipitation during this period reported is either in the form of rainfall or snowfall.
- It can be noted that many other parts of the country, like the Gangetic plains and northern states, also receive rain in November and December but this is not due to the northeast monsoon.
- It is caused mainly by the Western Disturbances, an eastward-moving rain-bearing wind system that originates beyond Afghanistan and Iran, picking up moisture from as far as the Mediterranean Sea, even the Atlantic Ocean. In the higher reaches of Jammu and Kashmir, Himachal Pradesh, and Uttarakhand, the precipitation is often in the form of snow.
- The northeast monsoon does not have anything to do with northeast India. It derives its name from the direction in which it travels, from the northeast to the southwest.
India Meteorological Department
- It 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.