'Human-Induced': Govt Report Warns of Rise in Heat, Cyclone, Flood

The report shows that by the end of this century the average temperature in India is likely to rise by 4.4°C.

Ministry of Earth Sciences (MoES) in their first-ever climate report titled 'Assessment of Climate Change over the Indian Region', has alerted us about the 'human-induced' harm done to India's climate and its disastrous ramifications during this century if correct measures are not adopted.

Some of the predictions and revelations in the report are worrisome for the country's climate future. The report shows that India's average temperature has risen by around 0.7°C from 1901-2018 and worryingly, by the end of this century the average temperature is likely to rise by 4.4°C.

In addition, the frequency of summer (April–June) heat waves over India might be 3 to 4 times higher.

The frequency and intensity of warm days and warm nights are also projected to increase over India in the next decades, while that of cold days and cold nights will decrease.

After analysing the data from 1901-2018, the ministry warns that the rapid changes in India’s climate will place increasing stress on the country’s natural ecosystems, agricultural output, and freshwater resources, while also causing escalating damage to infrastructure.

"The local climate change is influenced not only by the increase in the greenhouse gases but also by the increase in air pollution and the local changes in land-use pattern."

Dr Jayaraman Srinivasan, Distinguished Scientist, Divecha Centre for Climate Change, Indian Institute of Science

Sea Level Rise, Cyclones & Changes in Rainfall

Tropical Cyclone

Apart from rising temperatures, the intensity of tropical cyclones in the North Indian Ocean (NIO) basin will increase during the twenty-first century as per the report. It says that the frequency of very severe cyclonic storms (VSCSs) during the post-monsoon season has increased significantly during the last two decades (2000–2018).

Sea Level Rise

Since sea levels have risen globally because of the continental ice melt and thermal expansion of ocean water in response to global warming, it is predicted in the report that at the end of the twenty-first century, the steric sea level in the North Indian Ocean (NIO) will rise by approximately 300 mm relative to the average over 1986–2005, with the corresponding projection for the global mean rise being approximately 180 mm. In the last two and a half decades (1993–2017) sea-level rise occurred at a rate of 3.3 mm per year.

Changes in Rainfall

With continued global warming and anticipated reductions in anthropogenic aerosol emissions in the future, the report projects an increase in the mean and variability of monsoon precipitation by the end of the twenty-first century, together with substantial increases in daily precipitation extremes. The summer monsoon precipitation (June to September) over India has declined by around 6% from 1951 to 2015, with notable decreases over the Indo-Gangetic Plains and the Western Ghats.

Droughts & Floods

The report analyses that the frequency and spatial extent of droughts over India have increased significantly during 1951–2015. An increase in drought severity is observed mainly over the central parts of India, including parts of Indo-Gangetic Plains. These changes are consistent with the observed decline in the mean summer monsoon rainfall.

In addition, increased frequency of localised heavy rainfall on sub-daily and daily timescales has enhanced flood risk over India, concludes scientists. They said increased frequency and impacts of floods are also on the rise in urban areas.

Climate model projections done by the ministry indicate an increase in frequency, spatial extent and severity of droughts over India during the twenty-first century, while flood propensity is projected to increase over the major Himalayan river basins (e.g. Indus, Ganga and Brahmaputra).

Possible Climate Change Impacts

Another key message from the report by the experts is that the impacts of climate change are likely to pose profound challenges to sustaining the country’s rapid economic growth and achieving the sustainable development goals (SDGs) adopted by UN Member States in 2015.

The goals set are to end poverty, protect the planet and ensure that all people enjoy peace and prosperity by 2030.

The impact of climate change on the availability of freshwater is also a critical area of concern for India.

More impacts predicted by the experts:

• Country’s food security may be placed under progressively greater pressure due to rising temperatures, heat extremes, floods, droughts and increasing year-to-year rainfall variability that can disrupt rain-fed agricultural food production and adversely impact crop yield.

• Studies indicate that climate change may seriously compromise human health in the absence of risk mitigation, adaptation, or acclimatisation, particularly among children and the elderly.

• Rising temperatures are also likely to increase energy demand for space cooling, which if met by thermal power would constitute a positive feedback to global warming by increasing Greenhouse Gas (GHG ) emissions.

Dr Roxy Mathew Koll, Scientist, Indian Institute of Tropical Meteorology, Lead Author, IPCC Oceans and Cryosphere, says, "With the temperatures projected to rise by 2.7°C by 2040 and 4.4°C by the end of the century, we should be ready to face a further increase in the intensity, frequency and extent of these extreme weather events. Importantly, the chances of these extremes overlapping are large, multiplying the threat. We call them compound events. For example, an intense cyclone may be accompanied by heavy rains, storm surges as in the case of the recent cyclones. Or droughts may happen along with heatwaves."