Climate models indicate that global warming is expected to increase monsoon rainfall by 14% by the end of the century if greenhouse gas (GHG) emissions remain high (see graphic). In the medium emissions scenario, monsoon rainfall may increase by 10%.

How the torrential rain is happening due to climate change

• There have been two rain-bearing ‘low pressure systems’ that are active in the Arabian Sea as well as the Bay of Bengal since the past week.
• The low pressure system in the Arabian Sea contributed to the heavy rain in Kerala, whereas western disturbances, which are periodic influxes of moisture-laden clouds from the Mediterranean, and common during winter, are what caused the rain in northern India. The Bay of Bengal is still warm and strong winds from there are reaching as far as Uttarakhand and will contribute to rainfall in several parts of north-eastern India.
• Both low pressures as well as western disturbances are tangentially connected to the larger pattern of global warming. The Bay of Bengal is historically the warmer ocean that seeds low pressures and cyclones that bring rain to India. In recent years however, the Arabian Sea, too, has been warmer than normal, and leading to significant cyclonic activity. Overall elevated temperatures are also contributing to warmer waters in the Arctic Ocean and drawing colder air from the poles with greater intensity. This added to the increased moisture, thereby seeding more intense western disturbance activity over north India.

Analysis of monsoon

2021

• According to the India Meteorological Department (IMD), the Kerala and Mahe region received 124% excess rainfall from October 14 to October 20. Against the normal 72.1 mm rainfall for the period, the region had received 161.2 mm. Lakshadweep received 15% excess rainfall.
• Uttarakhand recorded 192.6 mm against the usual 35.3 mm from October 1 to October 20, with several districts reporting 24-hour highs that exceeded the figures from over a century.

Overall

• By 2100, monsoon rainfall could have changed by an average of 14% and as much as 22.5 percent.
• Between 1950 and 2015, overall rainfall during the monsoon season has dropped by 6%.
• There has been an increase in the frequency of dry periods during the monsoon season in recent decades, with a 27 percent increase between 1951 and 2011 compared to 1951-1980.
• Wet spells have also become more intense across the country, with central India experiencing 75 percent more extreme rainfall events between 1950 and 2015.

Negative Impact of climate change on monsoon

• The summer, or south west, monsoon, accounts for 70% of India’s annual rainfall and is crucial for its agricultural economy, which accounts for 11% of gross domestic product.
• The abnormally high rain in September could also adversely impact yield for some short duration monsoon crops
• Depletion of Water Table
• Fiscal Burden
• Impacting Electricity Generation
• Impacting Inflation
• Floods and droughts, both of which are dangerous to one’s health, are common in areas with a monsoon climate, particularly in dry weather.
• Heavy rains during the summer monsoon might create flooding. Floods cause widespread harm to persons and property, and they are exceedingly destructive. During the monsoon in Pakistan and India in the summer of 2014, over 300 people perished as a result of landslides and house collapses. The monsoon floods in Australia in 2011 cost the country $ 4.5 billion.
• Nonetheless, diseases like as cholera, dengue, chikungunya, and malaria, as well as stomach and eye infections, are the greatest health risks during the summer monsoon season.
• Soil erosion and degradation: Summer rainfall is intense due to the south west monsoon, resulting in significant runoff and soil erosion. In addition, soil erosion is an issue in huge parts of India due to the sudden monsoon burst.
• Rainfall with a high concentration

Way forward

• India’s population is growing, and in order to ensure food security, a considerable portion of the monsoon water that is currently unused should be stored in suitable sites for agriculture and power generation.
• In order to achieve reliability and sustainability, India needs to devote more resources to improving Monsoon forecasting.
• As the climate warms, more moisture will be trapped in the atmosphere, resulting in heavier rainfall. As a result, the monsoon’s inter-annual variability will grow in the future. This transformation necessitates preparation on the part of the country.
• As we live in a shared world with a shared future, we must take effective and timely steps not only on the domestic front (National Action Plan on Climate Change), but also on the international front (UN Framework Convention on Climate Change) to secure and bring sustainability to India’s climate pattern.

Climate change on a global scale is not a new phenomena. Climate change has a number of negative implications, one of which is causing changes in the southwest monsoon and its influence. India has set a goal to reduce greenhouse gas emissions by half by 2050. Coordinated efforts are urgently needed to improve studies on the effects of climate change on agriculture, forests, animal husbandry, aquatic life, and other living things.

How to structure:

• Give an intro about the monsoon
• Explain how the climate change is affecting the monsoon patterns in India, with diagrams/maps
• Illustrate with examples
• Also mention how it affects India- add different dimensions- agriculture, economy, water shortage, disaster management etc.
• Suggest way forward and conclude

Reference:

1. https://www.thehindu.com/sci-tech/energy-and-environment/explained-why-is-india-facing-bouts-of-extreme-weather/article37144380.ece