As a direct result of climate change due to rising global temperatures, Indian winters this year are expected to be drier and colder.
The forecast is based on a weather report compiled by Climate trends – a Delhi-based strategic communications company that works to raise awareness of the adverse effects of climate change on the environment.
The briefing mentioned that this year a weather phenomenon called La NiÃ±a is expected to return for the second year in a row. La NiÃ±a has the ability to change the direction as well as the speed of the trade winds, which trigger the winter season in India.
Also read: IMD issues severe cold snap warning for Punjab, Haryana, parts of Gujarat and northern Rajasthan
âNorthwest India is now gearing up for an extended winter season ahead, as well as record high temperatures in the Indo-Gangetic plains,â he said.
âAs we enter the height of the winter season, we would see a series of cold spells engulf both the hills and plains of northwest India. Similar to the characteristics of the La Nina season, minimum temperatures have already started to dip into the lower single digit, well below their average normal temperature, âthe briefing said.
Read also: “Despite a drop of 30%, winter air pollution in Delhi is expected to remain dangerous until 2030″
How climate change is affecting La NiÃ±a
According to scientists, global warming is expected to trigger more extreme events like La NiÃ±a and El NiÃ±o that affect India’s climate regime.
According to Michael McPhaden, senior scientist at the National Oceanic and Atmospheric Administration (NOAA), âIn a warming climate, extreme El NiÃ±o and La NiÃ±a events can increase in frequency from about one every 20 years to every 20 years. 10 years by the end of the 21st century in aggressive scenarios of greenhouse gas emissions â.
“The strongest events can also get even stronger than they are today,” he was quoted in an article published on the NOAA website on November 9, 2020.
Read also: Rising heat causing loss of labor; 162 hours lost per person per year in India, according to study
Also, according to a report by Nature published on January 25, 2015, global warming has increased the frequency of the extreme El NiÃ±o which provides favorable conditions for the extreme La NiÃ±a.
âThis is happening amid faster warming over the Maritime Continent region (the region between the Indian and Pacific Oceans) than the Central Equatorial Pacific and increasing vertical temperature gradients that are conducive to extreme La NiÃ±a events. The overall increase in the frequency of extreme La NiÃ±a events, most of which occur after an extreme El NiÃ±o episode, has important implications, âthe report said, citing the report.
“This means more occurrences of devastating weather events and more frequent fluctuations of opposing extremes from year to year, with profound socio-economic consequences,” he added.
The effect of La NiÃ±a on Indian winters
La NiÃ±a involves cooling sea surface temperatures over the eastern and central Pacific Ocean. It affects India by attracting the blast of the wind from parts of northern Asia, especially Siberia. The north-south movement of winds from Siberia towards the equator hits India intermittently and results in cold waves.
Raghu Murtugudde, professor of atmospheric and oceanic sciences and earth system sciences at the University of Maryland, currently visiting professor at IIT Bombay, was quoted in the briefing as: âLa NiÃ±a brings cold air from Siberia and southern China on the Indian subcontinent which interacts with tropical warming to produce a north-south low pressure system â.
WATCH: Why Kerala and Uttarakhand face frequent heavy rain disasters – says senior climate expert
âThe cold air associated with this north-south trough tends to extend much further south in India. This is remarkably different from the more northwest-southeast blast of cold air associated with an El NiÃ±o. In general, therefore, the cold air from La NiÃ±a occupies a much larger part of India than the cold air from El NiÃ±o, âadded the professor.
Other effects of La Nina on India
Climate trends noted that usual features of La NiÃ±a include reduced snowfall and winter rains in northwest India, which scientists believe would increase stress on the Himalayas which is already facing on the rise temperatures.
âWe know that the warming is not going to decrease and that any time there is low rainfall during the winter season, it will increase the stress on the Himalayan ecology. There would be increased climatic effects on vegetation. The situation would be quite worrying whether it is for agroforestry, the production of vegetation or fruits, etc. There is also a likelihood of glacier retreat, but at what rate is uncertain, âJagdish Krishnaswamy, dean, School of Environment and Sustainability, Indian Institute of Human Settlements was cited in the briefing.
The briefing mentioned that according to experts and scientists, the Himalayas are ecologically very fragile and with anthropogenic (man-made) factors, the region is quite vulnerable to natural disasters like flash floods, landslides and rains. torrential.
Argha Banerjee, Glaciologist, Earth and Climate Sciences, Indian Institute of Science Education and Research-Pune said, âMost of the snow on glaciers is brought in by the monsoon season. Snowfall in winter is very important because it provides snow cover for glacial ice. Snow is the only source of food for glaciers â.
âIt has been established that due to higher temperatures due to climate change and global warming, we are seeing more rain than snow. If there is less snowfall, there will be less snow accumulation on the glaciers. In addition, in the absence of precipitation, the spring melt season is also likely to start early. Glaciers would be exposed to solar radiation quite early in the season, which tends to melt much faster due to the already high temperatures. And this melting season would also be extended, âshe explained.