Why is Karachi, a coastal megacity of over 16 million, now facing deadly heatwaves that routinely push temperatures above 46°C? For decades, residents braved hot summers, but the intensity and duration of recent heat spells are unlike anything in living memory. What was once a seasonal challenge has become a public health emergency, with hospitals overwhelmed, power grids failing, and outdoor workers risking their lives just to earn a daily wage. As climate models grow more dire, the question is no longer whether extreme heat will return—but how often, how hot, and how unprepared cities like Karachi truly are.
Is This Heatwave Linked to Climate Change?
Yes—overwhelmingly so. Scientists now treat extreme heat events like those in Pakistan and India as clear manifestations of the climate crisis. According to the World Weather Attribution initiative, climate change has made such heatwaves at least 30 times more likely in South Asia over the past few decades. In Sindh province, where Karachi is located, April and May 2026 saw average highs exceed 45°C, with some areas reaching 48°C—a full 6–8°C above historical norms. The Intergovernmental Panel on Climate Change (IPCC) has long warned that densely populated, low-income urban zones near coastlines would face amplified heat risks due to both global warming and the urban heat island effect. Karachi, with its sprawling informal settlements and limited green space, fits this profile almost exactly.
What Evidence Supports the Climate Connection?
Data from Pakistan’s Meteorological Department and satellite observations from NASA’s Earth Observatory confirm a sharp upward trend in regional temperatures since the early 2000s. Between 2010 and 2026, the number of days exceeding 40°C in Karachi has more than doubled. A 2025 study published in Nature Climate Change found that humidity levels during these heatwaves have also increased, reducing the body’s ability to cool through sweat and raising the heat index to dangerous levels—sometimes exceeding 55°C. Dr. Ayesha Siddiqi, a climate resilience expert at the Aga Khan University, stated in a BBC interview: “We’re not just seeing hotter days. We’re seeing longer heatwaves, higher nighttime temperatures, and a collapse in people’s ability to adapt.” The World Health Organization (WHO) has classified Karachi as one of the most vulnerable cities globally to climate-driven heat stress, particularly among children, the elderly, and those with preexisting conditions like cardiovascular disease.
Are There Alternative Explanations for the Extreme Heat?
Some local officials and meteorologists have pointed to natural variability, such as El Niño events, as contributing factors. It is true that the 2025–2026 El Niño intensified warming across South Asia, but climate scientists stress that natural cycles now operate on top of a significantly hotter baseline caused by greenhouse gas emissions. Others argue that poor urban planning—not climate change—is the root problem, citing unchecked construction, deforestation, and lack of cooling infrastructure. While these issues exacerbate heat exposure, they do not explain the broader regional pattern of rising temperatures. Skeptics also note that Karachi has experienced hot spells before, such as in 2015, when a heatwave killed over 1,200 people. However, what’s new is the frequency: multiple extreme heat events now occur within a single season, leaving little time for recovery. As Dr. Fahad Saeed of the Climate Analytics group told Reuters, “This isn’t just bad weather. This is the new normal.”
How Is the Heatwave Affecting Daily Life and Public Health?
The human cost is already severe. In Karachi, hospitals have reported a 40% surge in heat-related admissions, including cases of heatstroke, dehydration, and kidney failure. Power outages, common during peak demand, leave millions without fans or air conditioning. Water shortages further compound the crisis, especially in low-income neighborhoods like Orangi Town and Malir. Outdoor workers—rickshaw drivers, construction laborers, street vendors—are particularly at risk; many say they have no choice but to work despite the danger. The Sindh government has issued heat advisories and opened temporary cooling centers, but access remains limited. Meanwhile, agricultural output in rural Sindh has plummeted due to crop failure and livestock deaths, pushing food prices up and deepening food insecurity. In some villages, schools have shifted to evening hours or closed entirely during the hottest weeks.
What This Means For You
If you live in or care about urban centers in tropical or subtropical zones, the situation in Karachi is a warning. Extreme heat is not just an environmental issue—it’s a health, economic, and equity crisis. Without better infrastructure, early warning systems, and climate adaptation policies, millions more will face life-threatening conditions in the coming decades. Individuals can help by supporting urban greening initiatives, advocating for heat-resilient housing, and staying informed about local heat risks.
But even as adaptation becomes urgent, a deeper question remains: can cities in the Global South withstand decades of intensifying heat without large-scale international support? The answer may determine not just survival, but the future of urban life in a warming world.
Source: The Guardian