Karachi and Islamabad sit at opposite ends of Pakistan's urban story. One is a sprawling, largely unplanned megacity of over 20 million; the other is the country's only fully planned capital, laid out on a tidy sector grid. Yet both are getting dangerously hotter and are experiencing a decline in green spaces.
Roughly 36% of Pakistan's urban population is already exposed to heat stress, a problem driven by climate change and compounded by increasing concrete and asphalt structures that absorb and re-radiate heat, as well as disappearing vegetation that used to cool cities down. Pakistan's national forest cover sits at just 4.5% of land area, far below the 25% considered healthy.
This piece walks through the rising heat crisis in Pakistan's cities, with a view of both planned (Islamabad) and unplanned (Karachi) cities.
Karachi: an under-planned economic hub. About 60% of Karachi's residents live in informal settlements characterised by congested housing built from heat-absorbing materials with little to no ventilation. Roughly 80% of the city's green cover has been overtaken by concrete since 2000. This trend is projected to continue. By 2040, urban land is expected to grow by 10.92%, while areas with land surface temperature (LST) above 30°C are projected to grow by 8.08% over the same period. Barren ground and vegetation, meanwhile, are both expected to decline.
Islamabad: planning that stopped adapting. Islamabad's master plan hasn't been revised in six decades, even though it was designed to be. The city's population hit 2.36 million in the 2023 census, up 18% since 2017. Islamabad's story is the same. Built-up land in the capital jumped from 18% to nearly 57% of the city between 1992 and 2012, more than tripling in just two decades. The E-11 sector presents a classic case of unregulated growth over green corridors and waterways. The sector now experiences up to 12 to 13 heatwave days on average, and modelling shows that even with tree-planting interventions, the area's heat-stress rating only drops from "extreme" to "strong", a reminder that greening has to be extensive and well-placed, not token.
Heat-risk assessment barely features in Pakistan's land-use bylaws or development approvals. Even though the Green Building Code of Pakistan includes interventions to mitigate the urban heat island (UHI) effect, the adoption of green building practice is held back by high upfront costs, a shortage of skilled labour, and weak code enforcement. Furthermore, the country's flagship tree-planting programmes, such as the Billion Tree Tsunami, the Ten Billion Tree Tsunami, and the Green Pakistan Programme, remain overwhelmingly rural in focus, without appreciably raising urban greening.
The problem thus lies on both sides of the spectrum. Built areas are increasing regardless of whether the city is poorly planned or well planned, encroaching on green spaces, and ultimately serving as one of the key factors in raising urban temperatures. Both Karachi and Islamabad, relatively economically superior cities, face the issue.
Going back to the basics would prove greatly beneficial in raising urban livability and mitigating heat in Pakistan. That involves planned development and nature-based solutions, specifically rebuilding green spaces.
Zoning by thermal temperatures would let planners direct green investment to the neighbourhoods that need it most and limit new construction in already-overheated zones. This needs to be paired with basic technical capacity: thermal mapping, green-coverage monitoring, and modelling at the community level.
This is where local evidence really should drive the agenda, instead of starting from scratch:
Build on Pakistan's own Miyawaki forest pilots. Punjab's Parks and Horticulture Authority has already established more than 50 dense, fast-growing Miyawaki-method micro-forests across Lahore, and the Islamabad Wildlife Management Board has piloted the same technique inside the capital. These mini-forests are self-sustaining after about three years and need only small parcels of land. Scaling this up could be beneficial in increasing green cover in dense neighbourhoods and under-vegetated sectors.
Treat mangrove restoration as heat infrastructure. A current IUCN-led project is restoring over 100,000 mangrove seedlings across 60 hectares of Phitto Creek, with local communities involved in planting and monitoring. Given that mangrove loss removed a natural buffer against both thermal and flood hazard along Karachi's coast, this kind of restoration sits firmly inside the city's climate-resilience planning, not off in a separate conservation lane.
Green infrastructure takes years to mature. The population living in congested informal urban settlements needs dedicated protection. Hospitals need "heat wards" with staff trained to recognise and treat heat stroke and dehydration quickly. Ahmedabad's Heat Action Plan, developed after a 2010 heatwave killed over 1,300 people, is credited with preventing an estimated 2,300 premature deaths a year and has since spread to more than 100 Indian cities. Its core pieces are strikingly low-cost and directly transferable.
For Pakistan's cities, a city-wide cool-surface plan offering subsidised reflective paint and green roofing, paired with revised summer school timings and shaded walkways linking schools, hospitals, and transit stops, would fit the existing sector-based grid well.
None of this sticks without two structural changes: formally listing urban heat as a priority hazard in Pakistan's disaster-risk strategy (it currently isn't), and redirecting a defined share of the country's existing tree-planting budgets, the Billion and Ten Billion Tree programmes, toward the cities where the exposed population actually lives, rather than leaving urban heat to compete for scraps of a rural-focused fund.
In conclusion, heat stress in Pakistan's cities doesn't distinguish between planned and unplanned development. What's encouraging is that the fixes aren't hypothetical. Solutions are within reach, and some have already been tested. The job now is to fund them properly, write heat resilience into planning law, and pair every tree planted with protection for the people who can't wait for it to grow.
Reach out and the editorial team will take it from there.
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