Although India is affected by extreme heat waves, since 1901 its average annual temperatures have grown by half compared to the global average.
What is about to start could be for India the third summer in a row characterized by extreme temperatures and devastating heat waves. However, if you focus on average annual temperatures, you can see that those of the Indian subcontinent they went up less than 0.7 ° C since 1901: practically half of the global average. The anomaly was confirmed in a recent conference on climate change organized by the Ministry of the Environment of India and the University of Harvard.
An exception that jumps to the eye. In a slide that showed the unprecedented increase in the middle temperatures of 2024 on a planisphere, and in which many countries appeared red with rapids of 1-2 ° C compared to the historical average, India distinguished itself for its pallor, even compared to other tropical countries: it is known that in the tropics, global warming advances less rapidly than in the poles, but the case of India also remains anomalous. How do you explain it? A popular article on Science There is three possible hypotheses, however not concluding.
Refressed mirror. The first is that the effect of the Global Warming on India is apparently slowed down by the very high concentrations of atmospheric pollutants, which on the indogangetic plain (India, Pakistan, Bangladesh) reach sadly famous levels. On November 18, 2024 in Nuova Delhi the concentration of atmospheric pollutants was 18 times higher than that of Milan, such as to produce a haze that even insinuated itself into the airport terminals, with the levels of PM2.5, the ultrafine particulate matter, 67 times higher than the limit values imposed by WHO.
Pollution that masks. More and more studies show that atmospheric particulates has partially masked, in the 20th century, global warming, both because some dusts to the sender of the sender the incoming solar radiation and because the particulates encourages the formation of clouds with a reflective effect. Assorting he must, because the polluted air kills (in India, more than one million people per year), but removing particulates has the effect of make “fall the mask” on the real scope of the global warming. The fact that the skies on the subcontinent are still saturated by pollutants has pushed some to explain the slow heating of India. Other scientists, however, are more cautious about this hypothesis.
Insufficient explanation. The aerosols that pollute the skies of India are in fact for a large part made up of particles of soot or carbon particulate, a dark powder that absorbs radiation rather than rejecting them. In addition, in the worst pollution period, in the winter months, the effect of global warming on India seems even more marked.
Therefore aerosols do not explain this seasonal trend.
Monsoni crazy. Behind the Indian anomaly there could also be a change of the monspoons triggered by the rapid heating of the Middle East. On North Western Pakistan and India, this phenomenon already caused the increase in extreme rains and floods.
Thanks to the water? The third possible explanation has to do with agricultural activities. In the last century India has gone through a decisive expansion of theirrigationespecially in the northern part of its territories. Scientific studies show that a massive increase in vaporized water or breathed by the leaves helps to lower temperatures on the surface. However, this last idea is not shared by everyone, especially because in summer, when irrigation is at a minimum for water scarcity, the heating deficit seems more pronounced.
More favorable elements. The most convincing explanation probably involves a set of many factors. Pollution and irrigation could exercise an influence on the climate at regional levelbut they also count the geographical position of India in the damp band of the tropics, as well as the variability of the climatic effects.
