Climate change is no longer limited to books or scientific papers; it is a reality knocking on our doors.

Longer, sweltering summers bringing in record-breaking heat to South Asia are just one example. The harshest of conditions have yet to come, and the entire region is woefully unprepared to meet the challenges.

While they may seem isolated, increasing instances of extreme weather are harbingers of a major climate shift for South Asia. Unlike transnational challenges like security and trade, climate change cannot be deterred by conventional methods or unilateral initiatives. Instead, synchronised common action is the viable way forward for sustainable progress to mitigate the impacts of climate change.

Let’s look at some of the common environmental challenges facing Pakistan and India and propose strategic measures to address them.

Heatwaves

Over the past decade or so, the frequency of extreme weather phenomena — ranging from blistering summers to freezing cold winters — has increased. Nearly half of these events were heatwaves, surpassing the previous record highs, and resulting in a wave of mortality around the world. Researchers point out that "the trend in global warming has contributed to the severity and probability of 82pc of record-hot days globally."

In Pakistan and India, heatwaves have become somewhat of a norm, an expected part of the summer. As a matter of fact, just last year, Pakistan saw the highest official temperature recorded in the world — 50.2 degree Celsius in Nawabshah — and a week later, that record was broken when Jacobabad hit 51°C.

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In 2015, a severe heatwave struck Karachi, breaking 40-year records, and resulting in nearly 2,000 casualties. As Edhi morgues and cemeteries started turning dead bodies away, a former head of the Environmental Protection Agency attributed the event to climate change.

Over in India, over 30 people died this summer as heatwave after heatwave resulted in temperatures near 51°C. Storms and rain brought little relief, as hundreds of thousands faced the brutal heat.

Survivability and wet-bulb effect

Experts warn that various areas in South Asia, including the Indus Valley in Pakistan, and much of India, would cross the survivability threshold by 2100.

Survivability was measured against what is known as the wet-bulb temperature, a factor based on both humidity and external temperature. It turns out that while our bodies are good at keeping themselves cool in heat, when you throw humidity into the mix, things go awry.

At 35°C, it becomes impossible for the human body to cool itself through sweating, and it enters survival mode. A few hours of sustained exposure to wet- bulb conditions, and you have imminent death — even in young, healthy adults in their prime.

While heatwaves have traditionally gained a strong foothold in the Indian subcontinent between March and July, their intensity, frequency and duration has been steadily increasing.

According to Elfatih Eltahir, a professor of hydrology and climate at Massachusetts Institute of Technology, "the future of heatwaves is looking worse even with significant mitigation of climate change, and much worse without mitigation."

Flooding

By far the most dangerous natural hazard that devastates Pakistan and India on a nearly annual basis is flooding. In the past 65 years, Pakistan has suffered from 30 major floods — the super flood in 2010 alone affected 20 million people.

Over in India, hundreds are killed and millions are displaced on an annual basis, as the monsoon intensifies short, heavy spells of rain. Just this year, monsoon-fueled storms killed around 270 in India, and left over a million displaced.

The continued rise in global temperatures spells further risk of flooding, as glaciers melt at a faster than normal rate. Glacial Lake Outburst Floods occur when a large amount of water, usually in a glacial lake, is released all of a sudden. They are often a precursor to flash flooding — a massive torrent of water picking up speed as it flows downhill, destroying everything in its path.

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In recent years, urban growth in both Pakistan and India has surpassed expectations. However, as more and more people flock to the cities, dilapidated infrastructure and poorly built settlements are becoming a common sight. Add to that a crumbling drainage and sanitation system, and you end up with the perfect recipe for urban flooding, the likes of which we have seen in Lahore and Karachi this year.

The situation is similar across the border, where rains lashed major towns and cities, leaving dozens dead and large swathes of infrastructure — roads, bridges, and railway lines included — under water.

Water stress

Pakistan is home to around 47pc of the Indus Basin, and India to around 39pc. The Indus Waters Treaty (IWT) has been in effect since 1960. Recent political bickering aside, the IWT has managed to survive the test of time, yet fails to comprehensively address climate change. Then again, at the time it was enacted, many of the stark realities that we know today were not understood.

According to the Pakistan Council of Research in Water Resources (PCRWR), Pakistan officially crossed the water scarcity line in 2005. The United Nations Development Program and the PCRWR have issued warnings about the upcoming scarcity of groundwater in just six years.

According to some estimates, Pakistan is the fourth-largest user of its groundwater, and over 70pc of drinking requirements and 50pc of irrigation needs are met through groundwater extraction. Due to excessive pumping, it is estimated that water tables could fall by as much as 20pc by 2025.

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Among the main contributors of water stress in Pakistan are poor water resource management and poor water service delivery, including irrigation and drainage services. Moreover, the lack of reliable water data, subsequent analysis and consequent poor planning and allocation is leading to environmentally unviable methods of water withdrawal, causing an alarming reduction in groundwater.

In India, water stress is attributed first and foremost to the massive population growth. Another cause is lack of sufficient urban water treatment facilities, which prevent the usability of river water for drinking and irrigation.

Like Pakistan, over-extraction of groundwater has also been recognised as a major contributor to water stress in India. Twenty one Indian cities, including Delhi, Chennai and Hyderabad are estimated to run out of groundwater altogether by 2020.

Agriculture

The South Asian region has historically been one of agriculture and livestock rearing. Indeed, the image of the trusty old farmer who sacrifices his body and soul for the land has been romanticised through the ages. But increasingly unpredictable weather patterns have started to disrupt agricultural activities.

In Pakistan, agricultural productivity is one of the lowest in the world. Adverse weather conditions caused a loss of nearly 1.5 million tons of wheat during the rabi season 2018-19.

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Over in India, thousands of tons of ready wheat were lost due to an unexpectedly heavy monsoon spell. According to a report by the World Bank, the agriculture sector makes up for more than 40pc of employment in Pakistan, and nearly 50pc of all labour in India is engaged directly or indirectly in agriculture.

Understandably, adverse effects of climate change on agriculture would not only hit the national economies hard, they would also threaten food security. Increasing populations in both Pakistan and India are likely to drive up demand for food, drawing in a looming imbalance between food demand and supply.

Drought

This brings us to another climate change-related conundrum: drought. Droughts occur frequently in Pakistan, and can affect as much as a third of the country at a single time. Balochistan, in particular, is hit hard because of its arid climate.

While structural arrangements to combat the effects of drought are well in place, issues such as lack of capacity, inability to tackle basin-scale water sharing challenges and lack of effective decision making further compound the problem. Earlier this year, the Pakistan Meteorological Department declared a drought in Sindh and Balochistan — over five million are estimated to have been affected.

In India, droughts have driven nearly 300,000 farmers to suicide in the past 25 years. Earlier this year, officials called the situation “worse than the 1972 famine”. Millions of farmers are simply abandoning their fields and livestock and moving to cities in search of work; there just isn’t enough water to go around. Meanwhile entire cities — like Chennai — are at the brink of a major disaster as water reservoirs run dry.

Smog

Over the past few years, smog has become a necessary precursor to the winter season, almost becoming a norm for the subcontinent. As vast swaths of land are set alight in northeastern India to prepare for sowing the wheat crop, plumes of smoke and highly carcinogenic particulate matter are carried over across the border to Pakistan.

There is no doubt that Pakistani farmers, too, burn their fields to get rid of parali in preparation for the next crop, but that is a drop in the bucket compared to the smog that is carried over across the border.

According to the National Aeronautics and Space Administration, for a few weeks in October and November (which coincidentally include the firework fueled festival of Diwali), Indian Punjab becomes a “major source of air pollution.”

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Here, it is crucial to talk about particulate matter, or PM, which is made up of a mixture of solid and liquid droplets of dust, dirt, soot and smoke which are divided into two broad categories. PM 10 are inhalable particles, while PM 2.5 particles can get embedded into the lungs and even enter the bloodstream.

Extended exposure to PM 2.5, a major part of smog, can lead to premature death in people with preexisting conditions, heart attacks, aggravated asthma, decreased lung function and various respiratory illnesses. Aged people and children are the most vulnerable to these effects.

What is the way forward?

According to climate researchers at Germanwatch, Pakistan ranks eight on the Global Climate Risk Index, with over 145 catastrophic events — heatwaves, droughts and floods — reported in the past 20 years. On the other hand, India ranks among the top 20 vulnerable countries in terms of climate risk.

There is no debating that both countries, and indeed South Asia at large, are highly susceptible to risks of climate change. Risks such as droughts, severe rains and flooding translate into decreased agricultural income and production and reduced food security.

A continuous cycle of heatwaves could lead to a public health emergency, where old and young may be the victims. Air pollution and smog could catapult rates of lung and breathing diseases, including asthma and cancer in the decades to come, debilitating an entire generation.

Action to mitigate the effects of climate change is needed to ensure adequate availability of water and food resources for future generations. Governments of both countries place climate change among their priorities.

In 2015, Pakistan reinstated the Ministry of Climate Change, while a year earlier, India expanded its Ministry of Environment to include Climate Change to its agenda of action. The Pakistan Climate Change Act, 2017 and India’s National Action Plan on Climate Change are a step in the right direction, at least on a domestic level.

With the IWT being held ransom, and rapidly melting Himalayan glaciers, we are likely to witness a reduction of water flow in rivers. Increased extraction of water from aquifers for drinking and irrigation purposes will amplify water stress, and researchers paint an alarming picture ahead: by 2025, Pakistan will, for the first time in its history, dip below the critical threshold of 1,000 cubic metres per year. In India, the per capita availability of water will be just over 25pc of what it was in 1951.

Water stress, exacerbated by these conditions, will spell disaster for the local populace. Already water stressed countries — such as Somalia, Syria and Yemen — have witnessed horrific violence over limited resources.

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With each passing year, the risks of unabated climate change to human lives and livelihoods are increasing. A bilateral agreement between India or Pakistan, through a forum such as South Asian Association for Regional Cooperation (SAARC), can be the first crucial step for addressing existing and emerging environmental challenges.

In order to address implementation issues due to topographic variations and state interests, the United Nations Environment Program can take the lead on such an initiative. A case in point is the dramatic shift in China-Japan relations which were transformed as the two nations began environmental cooperation through initiatives like the Sino-Japan Friendship Center for Environmental Protection at the Ministry of Environmental Protection of China, which was funded and operationalised by the Japan International Cooperation Agency.

Both the governments of Pakistan and India are actively promoting a transition towards sustainable, green economies and cutting down on carbon emissions and other contributors of climate degradation. India plans to have over a third of its installed power capacity reliant on renewable sources. In addition to being the fourth-largest wind power producer in the world, India is also home to some of the largest solar power parks.

In contrast, Pakistan has established solar parks, the largest of which is the Quaid-e-Azam Solar Park in Bahawalpur. A handful of windmill farms have also been established in coastal areas of Sindh and Balochistan. SAARC Energy Centre, based in Islamabad, is supporting the development of battery electric vehicles in Pakistan and India, with researchers at the Lahore University of Management Sciences and the Indian Institute of Management Bangalore paving the way for what could transform urban transport.

These initiatives, in addition to various other schemes, can prove to be the foundations of sustainable development for both nations. Increased cooperation between institutes of higher learning can be promoted to help identify potential risks, adopt and improve local best practices, and promote the exchange of practice and information between the two countries.

Looking at the climate change challenges Pakistan and India face together, collective action — as unlikely as it seems — may just be what is needed to secure the lives and livelihoods of future generations.

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