Climate change triggered monsoon fury in Uttarakhand, Himachal

Climate change has a big role to play in the devastating monsoon fury - flash flooding and landslides - in the northern Indian Himalayan states of Uttarakhand and Himachal Pradesh. 

According to experts, weather conditions might have been favourable for heavy rains, but climate change has a definite role in the increasing intensity.

The flash flooding and landslides have caused millions of rupees worth of damage and killed several people across the two states. 

The rise in extreme weather events is unprecedented, and they have been multiplying rapidly - and the monsoon 2023 is an apt reflection of what climate change impacts would do to the Himalayas if global warming goes unchecked, according to a paper collated by Climate Trends.

The atmosphere, land and oceans are all warming at a faster rate. The warmer it becomes, the more moisture the atmosphere can hold. This has led to more water being evaporated from the Earth’s surface. This increases the holding capacity of the air, which results in more droplets and heavier rainfall, sometimes in a shorter space of time and over a smaller area, the paper points out. 

“The Shivalik range is the youngest and most fragile part of the Himalayas as they are made up of debris. Rocks are made up of sandstone and shale rock, which is the weakest form of any rock, and they cannot withstand heavy rains as their composition is of clay minerals.

The increasing torrential rainfall, deforestation, and unchecked construction have increased the chances of erosion,” said Prof Y P Sundriyal, Head, Department of Geology, HNB Garhwal University, Srinagar, Uttarakhand.

“As humans, we have been challenging these mountains' capacity for many years now. Increasing anthropogenic stress will only lead to disaster,” he added. 

“During break-monsoon conditions, most monsoon rainfall activities get focussed over Himalayan foothills and to an extent over Himachal Pradesh and Uttarakhand. At the same time, other parts of the country, like Central India, witness dry weather conditions.

This is not new and has been happening ever since the existence of Monsoon. The science of global warming is clear that if we continue to emit more and more greenhouse gases into the atmosphere, especially CO2, it will enhance the air’s capacity to hold more and more water,” said Dr Akshay Deoras, Meteorologist and Research Scientist, National Centre for Atmospheric Science and Department of Meteorology, University of Reading, United Kingdom.

“Now, whenever favourable weather conditions appear, for example, in the case of break monsoon conditions, the air will release much more water vapour in the form of rainfall. This means the probability of an ordinary rainfall event intensifying into a heavy or extremely heavy one will increase because of global warming,” he added. 

“Monsoon rainfall patterns over India have seen a climatic shift in recent decades. The most significant change is that instead of having moderate rains spread out through the monsoon season, we have long dry periods intermittently with short spells of heavy rains. Hence this causes floods and droughts in the same season and occasionally in the same region or different parts of India. We saw this pattern manifesting during the current year,” points out Dr Roxy Mathew Koll, Senior Scientist at the Indian Institute of Tropical Meteorology, Pune.