What makes South Asia so vulnerable to climate change?

Heavy monsoon rains in Pakistan over the past week killed at least 50 people across the country, nearly a year after massive flooding killed more than 1,700 people and affected 33 million others.

In neighbouring India, about a dozen districts in the northeastern state of Assam were hit by deadly flash floods in June, forcing thousands to flee their homes and seek refuge at makeshift relief camps.

The ravaging floods – which killed at least 11 people – meant many faced the daunting task of rebuilding their lives as they returned to destroyed homes and drowned livestock.

Climate-change-induced downpours, drought, and soaring temperatures have become increasingly common across the eight countries of South Asia, making it one of the world’s most vulnerable regions to the impacts of global warming.

Saleemul Haq, director at the International Centre for Climate Change and Development, said the region is particularly at risk because of a combination of geography, population and poverty.

“Over a billion and a half people are living in an area that is not such a big part of the world. It has major river systems from the Hindu Kush and the Himalayan mountain regions flowing through,” he told Al Jazeera.

Some 750 million people in South Asia have been affected by at least one natural disaster, according to data compiled by the Washington-based World Bank.

The lack of land to grow food, water shortages, and displacement of populations are some of the challenges the region is facing as climate experts predict irreversible consequences to the livelihoods of hundreds of millions.

Food insecurity

For thousands of years, South Asia was seen as the world’s “granary” for agriculture – a region with weather patterns well-suited for growing crops, Pakistan-based climate scientist Fahad Saeed told Al Jazeera.

“However, with the onset of climate change, the delicate balance which was important for crops to grow has been disturbed,” Saeed said.

Results from a study published in 2021 on wheat production up to 2050, using crop simulation models, found the most negative effects will be seen in South Asian nations with a yield decline of 16 percent.

Environmentalist Anjal Prakash said climate change will have “significant implications” for food security in South Asia.

“Rising temperatures, changing precipitation patterns, and increased frequency of extreme weather events such as droughts, floods, and storms … pose substantial challenges to agricultural systems in the region,” said Prakash, adding livestock productivity and fisheries will be adversely affected.

Furthermore, Prakash said climate change could also make water availability of a significant issue in the region, which has one of the highest number of glaciers in the world, situated in the Himalayas.

“Melting glaciers and changes in rainfall patterns can disrupt irrigation systems, affecting crop growth and exacerbating water scarcity,” Prakash, who has previously worked with the UN’s Intergovernmental Panel on Climate Change, asserted.

A University of Leeds study published in 2021 found the ice from glaciers in the Himalayas is melting “at least 10 times higher than the average rate over past centuries”, a result of human-induced climate change.

Researchers said the Himalayas, which cover countries such as Pakistan, Nepal and India, had lost 40 percent of their ice over several hundred years.

Water scarcity and low crop yields will result in adding to the continuing hunger crisis in the region, climate experts said.

In 2021, the UN’s Food and Agriculture Organization (FOA) said some 21 percent of people in South Asia faced severe food insecurity, a 2 percent rise from 2020. In the same year, the region had the highest number of undernourished people in the world – 330 million – the FOA said.

‘Push factor’

Fears of declines in food production, together with other climate-related calamities such as rising sea levels, have also raised the alarm as millions in South Asia are being internally displaced.

A report published by activist group ActionAid in 2020 estimated the region could see up to 63 million people become migrants by 2050 as a result of extreme weather events.

Huq said displacement from human-induced climate change was further adding to economic migration from rural to urban areas – a continuing phenomenon worldwide – with South Asia being a major “hotspot”, with the greatest displacement taking place in low-lying coastal areas.

“Climate change … is exacerbating the ‘push factor’ – the motivation to migrate away from place of residence – for people who are living in places where they can no longer continue to have livelihoods that they used to have, whether it’s farming or fishing,” he said.

“From the damage that occurs to infrastructure, agricultural land and homes, many people that evacuate aren’t able to go home again. They become effectively refugees.”

In Bangladesh, Huq said an estimated 2,000 people were moving to the capital Dhaka, many displaced by the effects of extreme weather from lowland coastal districts such as Barisal and Satkhira.

“Dhaka is one of the fastest-growing megacities in the world. Absorbing many millions – possibly in the region of 10 million new climate migrants over the next decade – is just going to be impossible. Facilities are inadequate for the existing population. They’re going to be even more inadequate for the additional population,” said Huq.

Concerns for human health

Climate scientists also warned that extreme weather patterns are aggravating the dire health conditions in some of the world’s poorest regions, with South Asia being no exception.

Physician and climate analyst K Srinath Reddy of the Public Health Foundation of India said heavy rainfall and floods are a precursor for a myriad of vector-borne diseases.

“Malaria, chikungunya, dengue fever are already present as health challenges in South Asia, but they’re going to markedly increase because of several factors such as rising temperatures,” he told Al Jazeera.

“Mosquitoes can breed in warmer areas which have now opened up. In fact, as humans are wilting in the heat, mosquitoes become athletic and can rise to higher heights and so can spread farther and faster. You will find even hilly areas which were previously not malaria prone now much more malaria prone at higher altitudes.”

Meanwhile, the increased intensity of heatwaves in South Asia has been linked to illnesses, including cardiovascular and respiratory disease, Reddy said.

According to a study by the World Weather Attribution, deadly heatwaves in India and Bangladesh in mid-April were made 30 times more likely because of climate change.

A study published by Lancet in October showed India had seen a 55 percent rise in fatalities from extreme heat in the periods between 2000-2004 and 2017-2021.

Rais Akhtar, a climate expert and former professor at Jawaharlal Nehru University, said the dire state of health facilities in South Asia would make it easier for extreme weather to affect human health, especially in rural areas where most people live.

“In countries like Bangladesh and India, there is a dualism of sorts where in certain cities, there are well-established healthcare facilities. But in the rural, underdeveloped areas, these facilities are severely lacking … including shortage of doctors,” he told Al Jazeera.

People must travel to major cities to receive treatment, a costly ordeal for many.

Saeed, associated with German think tank Climate Analytics, noted in addition to weak health infrastructure in South Asia, governments do not possess the response and rescue capacity to provide adequate relief when climate-related calamities strike.

“The devastation from last year’s floods were so huge … affecting around 33 million people … that government authorities such the National Disaster Management Authority and hospitals were caught on their heels,” he said.

Moreover, the catastrophic floods also directly affected numerous health facilities across Pakistan, with the World Health Organization reporting more than 1,400 hospitals were destroyed or damaged, leaving thousands without access to medical care.