By Qamar Bashir
Former Press Secretary to the President
Former MD, SRBC,
Former Minister Press, Embassy of Pakistan to France
Global temperatures increasing by 2 degrees Celsius above pre-industrial levels will result in many regions experiencing prolonged periods of extreme heat, surpassing human tolerance. Specifically, the 2.2 billion residents of Pakistan and India’s Indus River Valley, the one billion people in eastern China, and the 800 million residents of sub-Saharan Africa will face annual challenges due to extreme heat.
According to recent studies, the outgoing month of September was exceptionally hot, deviating from pre-industrial levels by about 1.7 to 1.8 degrees Celsius. Had such an anomaly occurred in July or August, it could have exposed most parts of Pakistan to potentially unsurvivable heat. This underscores the urgency of addressing climate change and its impacts.
According to a recent World Bank study, Pakistan faces not only unbearable heat but also one of the highest disaster risk levels globally. It ranked 18th out of 191 countries in the 2019 Inform Risk Index. This risk is compounded by factors such as exposure to earthquakes, internal conflict, and various types of climatically induced flooding, including riverine, flash, and coastal floods, as well as some vulnerability to tropical cyclones and droughts. Pakistan’s vulnerability is further exacerbated by its social challenges, with a ranking of 37th out of 191 due to high rates of multidimensional poverty. However, it does score slightly better in terms of coping capacity.
The study adds to the growing understanding that there is a limit to how much heat and humidity the human body can endure, likely lower than previously believed. Moreover, exposure to such conditions is expected to increase significantly in the coming decades. Some of the hottest regions on Earth have already experienced periods where these limits are exceeded, highlighting the urgency of addressing climate change and its associated risks.
If nations across our precious but increasingly polluted planet fail to take decisive action to reverse climactic degradation, temperatures could eventually rise by 3 degrees Celsius above pre-industrial levels. At this point, even regions like the Eastern Seaboard and the central United States, stretching from Florida to New York and from Houston to Chicago, would experience unbearable levels of heat and humidity. This extreme heat would also affect South America and Australia.
Researchers at Penn State have identified a critical threshold, around a wet bulb temperature of 31 degrees Celsius (88 Fahrenheit), which would be problematic for young and healthy individuals not accustomed to such muggy conditions.
The combination of heat and humidity is indeed a lethal one. In such conditions, the air can’t effectively absorb excess moisture, which limits the evaporation of sweat from human bodies and moisture from infrastructure. As individuals become warmer, they sweat more, and blood is directed to the skin to help dissipate heat to the environment.
At certain levels of heat and humidity, even the natural adjustments become insufficient, and core body temperature starts to rise. This situation necessitates some form of relief. Without the means to cool down within hours, it can lead to heat-related illnesses such as heat exhaustion, heat stroke, and strain on the cardiovascular system, potentially resulting in heart attacks, especially in vulnerable individuals.
If such extreme heat and humidity were to occur in regions like Europe, where air conditioning is uncommon and people have low heat acclimatization, it could lead to mass fatalities or casualties, as emphasized by Carter Powis, the lead author of the study from the University of Oxford. This scenario holds true despite these nations generating fewer greenhouse gas emissions compared to wealthier nations. Consequently, billions of people in economically disadvantaged areas would suffer, and many could lose their lives. However, even wealthy nations won’t be immune to the negative effects of this heat, as our interconnected world ensures that everyone will be affected in some way.
The most severe heat stress will affect regions like Pakistan and India, along with other countries where affected people lack access to air conditioning or effective means to mitigate the negative impacts of extreme heat. This is especially concerning given the expected rapid population growth in these areas in the coming decades. Preliminary research indicates that older adults may experience heat stress and related health consequences at lower heat and humidity levels compared to younger individuals.
Take Lahore, Pakistan, for example, which is already a hotspot for climate change-related health issues. It is projected that by the middle of the century, Lahore could experience conditions that surpass the survivability threshold for two to three weeks each year, according to the study published in the Proceedings of the National Academy of Sciences. The study also noted that approximately 200 weather stations worldwide have already occasionally exceeded this bearable threshold.
To halt the rise in temperatures, researchers emphasize the critical need to reduce greenhouse gas emissions, particularly carbon dioxide emissions resulting from the burning of fossil fuels. Failure to make these changes will disproportionately affect middle-income and low-income countries.
As an example, consider Al Hudaydah, Yemen, a port city with a population of over 700,000 on the Red Sea. The study’s results indicate that if the planet warms by 4 degrees Celsius, this city could face over 300 days per year where temperatures exceed the limits of human tolerance, rendering it nearly uninhabitable.
In the hottest regions of the world, high temperatures and humidity will surpass a threshold that even young and healthy individuals could struggle to survive in as global warming continues. In Al Hudaydah, Yemen, such oppressive conditions are projected to last for a month or two, or, under the highest global warming scenarios, for most of the year.
Taking Lahore as another example, it would exceed the heat and humidity threshold for approximately 69.5 hours per year under the most conservative warming scenario. This translates to nearly nine days if the heat persisted for eight hours daily, or more than two weeks if it lasted for four hours daily.
This research underscores a stark reality – that the most severe impacts of climate change will disproportionately affect countries that have contributed the least to its creation. Fahad Saeed, a climate scientist with the German think tank Climate Analytics, highlights that much of the worst and most persistent heat will occur in densely populated and underdeveloped regions of southern and southeastern Asia and Africa.
It’s important to note that humid heat poses a greater threat than dry heat, and governments and policymakers need to reevaluate their heat-mitigation strategies to prioritize addressing these significant dangers that people will face.
Furthermore, for resource-scarce countries like Pakistan, the challenge isn’t limited to the lethal combination of summer heat and humidity. Regions like Punjab face a complex issue of smog, which obscures sunlight and creates a cooler yet polluted environment. Cities like Lahore, Faisalabad, and Gujranwala, in addition to being the most populous and polluted in Punjab, grapple with worsening smog problems that intensify every winter.
Major contributors to this issue include traffic pollution, crop burning, and industrialization, resulting in significant health problems, including respiratory, eye, skin, and heart-related issues..
While the government has taken some measures to address the dangerous effects of smog, these efforts have proven to be of limited significance. Substantial and coordinated efforts are still required, and public cooperation will play a pivotal role in combatting this issue effectively.
It’s important to note that Pakistan is not alone in facing the deadly combination of summer heat and humidity, as well as winter smog. Climate change is pushing temperatures higher across the globe, pushing billions of people beyond the bearable limits of heat and humidity.
The resilient people of Pakistan, like many others worldwide, will need to confront climatically induced disasters year-round, from extreme heat and humidity in the summers to smog in the winters.
They must prepare themselves for the challenges posed by both natural and manmade climatic issues before health problems related to heat, humidity, and smog, such as heat strokes, heart attacks, and lung, eye, and skin diseases, become more prevalent. This proactive approach is crucial to safeguarding their well-being in the face of these environmental challenges.
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