Experts Warn Of Harsher Heatwaves In India

Workers transport large bunches of bananas across the market loading area under the scorching sunlight at Koyambedu Market, Chennai (Photo by McKay Savage/Wikimedia Commons)

A recent UN report has suggested that the next five years could be the hottest on record as global temperatures rise above the 1.5-degree Celsius limit.

The new update released by World Meteorological Organisation (WMO) discusses the upcoming El Nino, combined with heat-trapping greenhouse gases, which will result in global temperatures between the years 2023 and 2027 rise to over 1.5°C above pre-industrial levels for at least one year.

Pre-industrial levels are the level of temperature at any period before the industrial revolution. The Intergovernmental Panel on Climate Change’s (IPCC) special report uses the reference period 1850–1900 to represent pre-industrial temperature.

The average global temperature in 2022 was about 1.15°C above the 1850-1900 average. The cooling influence of La Niña conditions over much of the past three years temporarily reined in the longer-term warming trend. But La Niña ended in March 2023, and an El Niño is forecast to develop in the coming months. Typically, an El Niño increases global temperatures in the year after it grows – in this case, this would be 2024, the WMO report said.

Dr. Leon Hermanson, the lead of the report and a Met Office expert scientist, said, “Global mean temperatures are predicted to continue increasing, moving us further and further away from the climate we are used to.”

The report also talks about the changing temperatures in the Arctic. “Arctic warming is disproportionately high. Compared to the 1991-2020 average, the temperature anomaly is predicted to be more than three times as large as the global mean anomaly when averaged over the next five northern hemisphere extended winters,” it says.

Past studies have shown that warm and cold climatic conditions in the Arctic have led to erratic monsoon patterns in India. A climate reconstruction study found that warm Arctic conditions were linked to intense rainfall over the Indian subcontinent, while cold conditions in the Arctic were associated with weak spells of rain over the Indian subcontinent over the past 1,000 years.

What It Means For India

India is experiencing an increasing frequency and duration of heatwaves because of global warming. And with the El Nino Southern Oscillation (ENSO) coming in, the period of heatwaves is expected to be longer.

“The findings of the WMO update can be highly correlated with the current occurrence of heatwaves across India. 2023 is the second year in a row that India has witnessed untimely heatwaves. After recording the warmest March last year, this year India recorded its warmest February since records began in the early 1900s,” said Vishwas Chitale, Senior Programme Lead at Council on Energy, Environment and Water.

“According to a report from World Weather Attribution, the intensity of the 2022 heatwave in India was found to be 30 times more likely as a result of climate change caused by human activities,” he added.Many parts of South Asia, including India and Pakistan, experienced long spells of hot weather during the months of March and April 2022. The month of March was the hottest in India since 1901, with temperatures consistently being 3°C-8°C above average, a report from Indian Meteorological Department (IMD) suggested. States of Odisha, Madhya Pradesh, Gujarat, Chhattisgarh, Telangana, and Jharkhand were severely affected during this period.

“There has been historical warming over India, with 2022 being the fifth warmest year on record. This is consistent with expected warming due to anthropogenic climate change. In addition to this background warming, short-term ENSO oscillations modulate year-to-year climate variability, particularly over the tropics. With the developing El Niño, it is possible that 2024 will be the, if not one of the, warmest years of record for the country,” said Earth scientist T.C. Chakraborty. Chakraborty is a staff scientist in the Earth System Modeling Group under the Atmospheric Sciences and Global Change Division of the Pacific Northwest National Laboratory in the US.

India Needs Better Preparedness

The rise in global temperature will lead to negative impacts on human lives not just during the heat spells but also throughout the year.

“A warming El Niño is expected to develop in the coming months, and this will combine with human-induced climate change to push global temperatures into uncharted territory,” said WMO Secretary-General Prof. Petteri Taalas. “This will have far-reaching repercussions for health, food security, water management, and the environment. We need to be prepared,” he added.

The extreme heat conditions in India impacted the production of wheat in the country last year. The government was forced to ban wheat export because of the same reason, in order to maintain food security. India witnessed a shortfall of about 4.5 million tonnes in wheat production against its aims of 111.32 million tonnes in 2022.

To better quantify the impact of climate change on public health, Chakraborty stresses the need to look at both air temperature and humidity, which can both be high in many parts of the country, especially along the coasts.

“While historical warming in many circumstances has been accompanied by improvements in climate adaptation strategies, such as access to air conditioning and better heat advisories, there are costs associated with this. Moreover, these advantages are more relevant for white collar workers, people living in modern housing, and those with access to air-conditioned transit options (including personal vehicles). Many people in India live in slums, non-electrified villages, etc., where such modern infrastructures are not available.

For instance, around 41%, 30%, 28%, and 15% of the population of Greater Mumbai, Kolkata, Chennai, and Delhi, respectively, are estimated to live in slums as of 2017. Indian agriculture is also less mechanised, which leads to more workers being exposed to outdoor conditions. Overall, the impacts of present and future outdoor heat stress will be felt by a larger fraction of the population in India and other neighbouring nations than in many Western countries,” he said.

Many Indian states and cities have their own Heat Action Plans to tackle the frequent heatwaves and increasing temperatures. But experts have mostly raised questions on their feasibility in terms of local context and oversimplified view of the hazard.

“At the policy level, India needs to strengthen its Heat Action Plans (HAPs), which have been able to reduce heat mortality by incorporating granular heat risk assessments and critical heat stress indices, which also incorporate humidity. Moreover, the current disaster relief fund guidelines do not include heatwaves as a disaster eligible for utilisation of funds. States can declare heatwaves as a disaster in the ‘local context,’ but it limits their spending ability to only 10 percent of the total funds. The nodal disaster and meteorological agencies should address these gaps to prepare better, said Chitale.

“It is now imperative to understand the associated and compounding events of these extremes to prepare better. Analysis of climatic vulnerability across different sectors and building a resilience action plan suited to the local contexts can play a crucial role in building resilience at the community level,” he added.

(Published under Creative Commons from Mongabay-India. Read the original article here)