Rapid industrialisation over North India has taken its toll on climate. A study conducted at the Indian Institute of Technology,Delhi,says the northern part of the country has had a more rapid temperature change compared to the southern part. The study takes into account the gradual increase in temperatures over 100 years from 1901 to 2003 and concludes that while both regions have had an average maximum temperature increase of close to 0.75 degree Celsius,the rise in North India has taken place over 20 years and that in South India occurred over a period of 30 years.
In both the regions,the rise in temperature has been more prominent between October and February. However,the fluctuations in temperatures are more prominent in North India. Between 1955 and 1970 there has been a sharper decrease in minimum temperatures in North India compared to that of South India. From 1975 onwards,North India beat South India in terms of the magnitude of rise.
The research,Variability of Climate Change in India,by Sushil Kumar Dash and J C R Hunt does not talk about the reasons that may have led to a faster temperature change in North India. However,talking to The Indian Express,Dash says the probable reason can be the increased amount of suspended particles over North India where industrialisation and construction have taken place at a greater speed. It is difficult to pinpoint the exact reason for the difference between the two regions. But aerosols in the air due to rapid industrialisation could be one of the factors. Aerosols suspended in air prevents the earth from cooling down in the night and thus increases the minimum temperature, he says.
Dash teaches at the IIT,Delhi,while Hunt is a member of House of Lords. In their study,they have divided India in terms of geographical area and studied climate change during different periods: pre-monsoon,monsoon,post-monsoon and winter. According to the study,one of the factors leading to temperature change in India is the increase in water vapour in the atmosphere due to evaporation caused by temperature rise. If the water vapour condenses,it forms clouds. With temperature rising,it remains suspended in the atmosphere in the gaseous state,adding to the greenhouse effect. The researchers predict that this will lead to a temperature rise of 4 degree Celsius by 2100.