North India’s monsoon mayhem

Source– The post is based on the article “North India’s monsoon mayhem” published in “The Hindu” on 12th July 2023.

Syllabus: GS 1 – Geography

Relevance: Climatology of India

News-. The article explains the pattern of monsoon this year and factors influencing monsoon.

What has been the pattern of monsoon this year?

Monsoon onset was delayed by Interactions between typhoons and cyclones. Cyclone Biparjoy delayed the arrival of monsoon over Mumbai by nearly two weeks.

The monsoon in Mumbai arrived together with Delhi for the first time in over half a century.

The distribution of rainfall remains patchy. Excess rainfall is witnessed over the northern Western Ghats and northwest India. There is deficit in Uttar Pradesh, Odisha, Chhattisgarh, Madhya Pradesh, and Maharashtra.

Extreme heat has also been reported even with heavy rainfall in some areas of Himachal Pradesh.

What are the factors influencing monsoon in India?

Global warming creates a warm, humid atmosphere, which acts like a drug for the weather. All weathers are affected by global warming.

Weather patterns are also caused by other factors. One such factor is the El Niño.

Wildfires have led to burning over three times the normal area and emitted about three times the normal amount of carbon dioxide. This has caused warming.

The strongest winds break into clockwise or anticlockwise patterns in the upper atmosphere, especially in mountainous terrain, like the Himalayas.

The strong clockwise winds of the upper atmosphere require an anticyclonic circulation near the surface to feed the upper-level outflow. This convergence near the surface causes excess rainfall.

The warming over the Himalayas has not been uniform. Some parts in the mountain chain are impacted by local warming. During the monsoon, the local features impact the weather pattern. This can lead to cloudbursts, heavy rains, or even heat waves.

What are the factors that are having an influence on monsoon rainfall this year?

Rainfall over northwest India is in line with the fact that the Arabian Sea has warmed by around 1.5 degrees Celsius since January.

This year, pre-monsoon rainfall has been higher than normal due to the warm Arabian Sea, combined with an unusually high frequency of western disturbances. Soil has been left moister than normal, which has impacted the monsoon development.

The monsoon is also influenced by the Atlantic Ocean. The entire Atlantic has been warmer than average since March. An Atlantic Niño, with a warmer tropical Atlantic, usually tends to dampen monsoon rainfall. The effects of this on monsoon this year are unclear.