Record early heatwave in south Asia

 From Indrastra

Maximum temperatures in India and Pakistan have been continuously over 40 degrees Celsius for almost a fortnight, exceeding the average for early April by up to 10 degrees Celsius in certain regions.

For days at a time in early April, people and animals across large swathes of India and Pakistan lay gasping in whatever shade they could find as the temperature exceeded 43 degrees Celsius and dry wind from the desert seared the plains of Indus and Ganga river basins. As Delhi recorded a maximum of 42.6C on 11 April, 7C above average for this day of the year, there was just one topic of conversation when people ventured out after dusk: nobody could remember such an early heatwave. Few could remember 40-plus days before May or June when such temperatures would be expected.

Meanwhile, across Central Asia, people used to far cooler weather suffered as the thermometer reached the 30s.

The early heatwave was particularly grueling for those fasting during the Muslim holy month of Ramadan – when the faithful do not even drink water between sunrise and sunset – and the Hindu holy period Navratra. Residents of urban slums fared the worst under tin or asbestos roofs.

Weather forecasts promised little relief, just more warnings of heatwaves across Punjab, Sindh, and Rajasthan on both sides of the India-Pakistan border, then eastwards across Haryana, Delhi, Uttar Pradesh, Madhya Pradesh, and beyond. A few rain-bearing clouds blowing from the Caspian Sea evaporated by the time they reached the Himalayan foothills.

The early heatwave scorched the plains of Pakistan, including megapolis Karachi, reminding residents of 2015 when at least 1,200 people died due to severe heat in Sindh province, of which Karachi is the capital. Hot winds from the desert pushed the sea breeze away from the coast.

In what many called a spring-less year, 2022’s winter suddenly transformed into scorching summer when Pakistan experienced an unprecedented heatwave in March. An advisory issued by the Pakistan Meteorological Department (PMD) on 15 March warned that day temperatures would remain unusually high in most parts of the country during this period. As forecast, record-breaking temperatures were recorded in some cities. Shaheed Benazirabad in Sindh recorded temperatures of 45.5C on 27 and 28 March.  

According to a second PMD warning issued for the first week of April, daytime temperatures were expected to remain 9-11C above normal in Sindh, South Punjab, and parts of Baluchistan, and 8-10C above normal in northern Punjab, Islamabad, and even in the mountains.

Local media reported that the early heatwave has led to more fires on farms in Pakistan as well as India, just as the winter wheat crop is ready to be harvested. Authorities in Pakistan are also worried about increased evaporation from water reservoirs in a country already facing severe water stress.

If heatwaves were to be mapped, Jacobabad, Bahawalnagar, Bahawalpur, Hyderabad, and Karachi would emerge as red dots. Earlier this year, the Intergovernmental Panel on Climate Change (IPCC) warned that Pakistan will likely face longer and more intense heatwaves as a consequence of climate change, even if global temperatures rise by only 1.5 or 2C.

In this situation, what seems to be sorely missing is any clear plan of action by government departments. Other than sporadic public service messages, there is little forethought or groundwork to save local communities from the impacts of heatwaves.

It is supposed to be spring in Central Asia, but temperatures have reached midsummer levels of 30-33C in Uzbekistan, 8-10C above average for early April. Temperatures in northern Kyrgyzstan including the capital Bishkek hit 26-28C in the first week of April, again well above average.

All records were broken in Ashgabat, the capital of Turkmenistan, when the thermometer reached 36.6C, 6C higher than the previous record for this date in 1991.

Heatwaves have more severe impacts in areas unused to them. A 2021 heatwave in Kazakhstan’s Mangystau region killed more than 1,000 livestock, with farmers scrambling for insufficient supplies of livestock feed. Sustained periods of unusually high heat can also impact regional water supply. Facing prolonged drought in 2021, Uzbekistan and Kazakhstan, downstream countries of the rivers flowing from the Hindu Kush Himalayas, reportedly sought ‘guarantees’ of uninterrupted water supply from upstream countries Kyrgyzstan and Tajikistan.

Scientists classify heatwaves as one of the earliest and most obvious impacts of climate change. This year’s early heatwave has come as the average global temperature stands at 1.17C higher than in 1850, at the start of the Industrial Age. Governments have pledged under the 2015 Paris Climate Agreement to keep this temperature rise to within 2C, and strive towards a ceiling of 1.5C, though their current actions are putting the world on course for a rise of at least 2.7C by 2100.

According to a 2021 study, deadly heat stress conditions might become common across South Asia even at 1.5C warming. The authors point out that ‘wet bulb temperatures’ above 32C affect human productivity, while 35C is considered the limit of human survivability, and that parts of South Asia are already experiencing these conditions.