The devastating impacts of the changing climate are not a distant reality. Regions across the world are already feeling the impacts in the forms of extreme weather events and disasters. This year alone witnessed heavy snowfall in Spain, wildfires in North America, severe flooding in Europe, sandstorms in China, and ongoing heatwaves in USA and Canada. India also witnessed two destructive cyclones affecting the east and west coasts, causing heavy damage to life and property.
With so much going on, sometimes reality seems to mirror apocalyptic movies. Intergovernmental Panel on Climate Change (IPCC) reports provide proof of the role of humans in accelerating climate change. Anthropogenic activities are estimated to have caused a 1-degree Celsius increase in global warming above pre-industrial level, and with the current rate of increase, it is likely to reach 1.5 degree Celsius between 2030 and 2052. A national report by the Union Ministry of Earth Sciences says the temperature over the Indian subcontinent rose by 0.7 degree Celsius between 1901 and 2018 and is estimated to increase up to 4.4 degree Celsius under the worst-case scenario.
Such rapid increases in temperatures throw the delicate global climate system off balance which is seen in the form of deadly heatwaves, intense droughts in some regions, and floods, severe cyclones, and thunderstorms in others. During 50 years (1979-2019), Extreme Weather Events (EWEs) have killed 1.4 lakh people in India, with the greatest number of deaths due to floods followed by lightning, heat wave, and cold wave, according to a recent study published in Weather and Climate extremes.
The states most affected by EWE mortality were Odisha, Andhra Pradesh, Assam, Bihar, Kerala and Maharashtra. Heatwaves are marked by abnormally high temperatures in a region. The number of deaths due to heatwaves saw a staggering 161 per cent increase during 2010-19 compared to 1970-79, based on EnviStats India 2021, released by the National Statistical Office (NSO). In 2019, one of the three warmest years on record, India faced a deadly heatwave with 65 per cent of the population exposed to the extremity and 210 people killed.
The frequency, intensity, duration and coverage of heatwaves is going to increase substantially over the sub-continent in the coming years according to the Assessment of Climate Change over the Indian Region report, Ministry of Earth Sciences. The southern part of the country, currently not influenced by heatwaves, is projected to be severely affected by the end of the 21st century. The overall trend of cyclones over the North Indian Ocean (NIO) is decreasing, but a sudden spike in cyclones in 2019 increased the number of cyclones in this decade compared to the last.
A total of 8 cyclonic storms formed over NIO in 2019, out of which five were in the Arabian sea against the normal of 1 per year, according to the IMD official statement. Cyclonic storms were also said to have more intense development. Correlation has been found between formation of such intensified cyclones and warming sea temperatures, leading to cyclonic storms even over cooler waters like the Arabian sea, a rare occurrence as lower sea surface temperatures dissipate cyclone formation. Warming Arabian Sea is also a cause of concern for Western Ghats and central India as warmer moisture-laden air will bring intense rain episodes.
The warming also fuels rapid intensification, as seen in recent cyclones Amphan and Tauktae, and makes their behaviour unpredictable. Cyclone Amphan, which hit the eastern states of the country in 2020, claimed 90 lives and is reported to have been the costliest tropical cyclone in NIO, resulting in $14 billion worth of economic loss. Though the overall trend of cyclones is said to be decreasing, the frequency of very severe cyclonic storms is likely to rise in the coming century. With the rise in surface temperature and increased moisture in the air due to heating, the sea level rises and the storm winds become stronger, causing more damage to life and property.
Rainfall over the Indian subcontinent is decreasing overall but becoming increasingly erratic at the same time. The summer monsoon saw around 6 per cent decline from 1951 to 2015, notable over the IndoGangetic Plains and the Western Ghats. On the other hand, more intense wet spells were observed during the summer monsoon season. The frequency of daily precipitation extremes has increased by about 75 per cent during 1950–2015 over Central India. Consistent with the decreasing trend of annual rainfall, the frequency and spatial extent of droughts over the Indian region have increased between 1950 and 2015, MoES report states.
The area affected by drought has grown by 1.3 per cent per decade and the frequency of multi-year droughts has also increased mainly over central India. Another natural disaster heavily affected by rainfall patterns are floods. They are one of the deadliest disasters and also an annual occurrence in many parts of the country. According to a recent paper, during 1970-2019, floods had a major share in disasters and were responsible for maximum mortality (46 per cent).
Uttar Pradesh, Maharashtra, Uttarakhand, Andhra Pradesh, Bihar and Assam were the most affected states. The paper also reported that floods caused by EWEs resulted in $3 billion economic losses per year in India. The MoES report states that flooding events have been increasing since the 1950s, mainly due to localised, short-duration, intense rainfall. The Indus, Ganga and Brahmaputra basins are at high risk of flooding in absence of proper mitigation measures.
With expanding sea level, poor infrastructure, rapid urbanization, and extreme rainfall events, the frequency of floods, especially coastal and urban floods, as well as the population vulnerable to this calamity, will rise significantly in the future. Lightning is one of the most dangerous and lesser-known events in the country. Recently 38 people died due to lightning strikes in a span of 24 hours, with a dozen of them killed in a single lightning event in Jaipur city.
According to National Crime Record Bureau records, lightning has claimed 46,900 lives between 2000 and 2019. Shockingly lightning is not yet notified as a natural disaster by the Government of India and most states despite being such a deadly phenomenon. A Lightning Resilient India Campaign was launched in 2019, a joint initiative of Climate Resilient Observing Systems Promotion Council (CROPC), National Disaster Management Authority (NDMA), IMD, Union Ministry of Earth Sciences and NGOS, to minimise deaths due to lightning.
According to Campaign Report, rural areas are more affected by lighting than urban areas, which is attributed to rural pattern of working in open vulnerable spaces and lack of awareness among people. The report also mentions that the lightning strike frequency has increased due to global warming, environmental degradation and sudden weather changes resulting in cloudbursts, cyclonic storms, and thunderstorms. The percentage of glacial lakes with increasing water spread is showing a growing trend over the past years, based on the EnviStats 2021 records.
This may be indicative of the rising temperatures causing melting of ice and feeding the glacial lakes with meltwater. The surface temperatures over Himalayan region are warming faster compared to global averages. This could lead to faster melt of glaciers which could cause overflow in glacial lakes in unstable conditions. Glacial lakes are potential sources of devastating floods called Glacial Lake outburst flood (GLOF). GLOFs are considered to be one of the most extensive glacial hazards in terms of damage potential. Himalayan states are likely to be at high risk in future with increasing pressure on the Himalayan system and destabilisation of natural structures.
There is overwhelming evidence pointing towards worsening disasters all over the world. The impact of such extreme events, aggravated by climate change, is not uniform. It is projected to affect developing countries more, especially the tropical poor. India is also likely to suffer badly in future. The country ranked 7th worst hit in the Global Climate Risk Index 2019, in a report prepared by Germanwatch, a global think tank. It is worth noting here that while it is imperative to curb warming temperatures, it is also pointed out by scientists that even if all the 2015 Paris commitments are met, global warming is still likely to exceed 3 degrees Celsius by the end of this century and therefore needs immediate action.
The high geographic and socioeconomic diversity in a country like India makes the task highly complex and challenging. India has seen a lot of improvements in early warning systems for various disasters and better disaster preparedness which has proven successful in reducing total fatalities. But the looming dangers of climate-associated extreme events cannot be denied and planning is the need of the hour. Technological advancements, along with better mitigation and adaptation measures, streamlining of disaster management in development policies and improving last mile delivery systems are some of the important ways to prepare for the inevitable incoming threats of extreme weather events and disasters in the coming years.
(The writers are, respectively, a postgraduate in Environmental Sciences from Savitribai Phule Pune University and a senior research fellow at IIPS Mumbai)