The WWA findings echo warnings from the Intergovernmental Panel on Climate Change, which has consistently projected an increase in heavy monsoon rainfall for South Asia.

Human-caused climate change has made the intense monsoon rains that devastated northern Pakistan in June and July this year significantly more severe, according to a new analysis by the World Weather Attribution (WWA) initiative.

The report, released this week by an international team of scientists from Pakistan, Sweden, Denmark, the UK and the US, concludes that the 30-day peak rainfall that triggered flash floods in Punjab and Khyber Pakhtunkhwa was about 15 per cent heavier because of global warming. In some climate models that better capture regional dynamics, the increase could be as high as 40–80 per cent, in line with observed data.

The study examined rainfall from late June to late July 2025, a period when repeated storms inundated the cities of Islamabad, Rawalpindi, Chakwal, Faisalabad, Peshawar and Lahore. Rawalpindi endured its worst single day of rain on July 17, with 230 millimetres falling in less than 24 hours, overwhelming drainage systems and forcing mass evacuations along the Lai Nullah.

“This is not a rare event anymore,” the scientists said, noting that in today’s climate, warmed by 1.3°C since pre-industrial times, such rainfall is expected roughly every five years. “But climate change has clearly increased its intensity, making its impacts deadlier.”

A High Human Toll

The National Disaster Management Authority (NDMA) reported that by August 3, 300 people had died and 715 had been injured nationwide. Punjab recorded 162 fatalities and Khyber Pakhtunkhwa 70. Children accounted for nearly half the deaths – 140 in total – with many killed when homes collapsed under the weight of waterlogged mud walls and rooftops.

Over 1,600 houses were damaged or destroyed, and at least 164 deaths were directly caused by building collapses. “The vulnerability of children and the fragility of informal housing are two urgent issues Pakistan must address if it is to prevent similar tragedies,” the WWA report stressed.

From Local Deluge to Global Signal

The researchers analysed both observational data and climate model simulations to determine the role of human activity in altering rainfall extremes. Historical observations showed a 22 per cent increase in 30-day maximum rainfall compared to a pre-industrial climate, driven largely by fossil fuel emissions and deforestation.

Climate models, though less accurate in simulating South Asia’s complex monsoon systems, still indicated a 12 per cent increase in intensity. Two models that realistically represented aerosols and irrigation – both major factors in regional rainfall – showed much larger increases of 40–80 per cent.

“The best available evidence suggests that climate change made this season’s extreme rainfall substantially more intense,” the report noted, adding that uncertainties remain high but point to a consistent upward trend in risk.

A Mirror of the Past, a Warning for the Future

The 2025 floods come just three years after the historic 2022 disaster, which submerged a third of Pakistan, killed more than 1,700 people and caused an estimated US$30 billion in losses. While that catastrophe was driven by an exceptional accumulation of monsoon rain over weeks, the WWA findings show that shorter, intense bursts of rain – like those seen this year – are also being turbocharged by climate change.

Looking ahead, the study warns that under a 2.6°C warmer world, 30-day extreme rainfall events of this magnitude are likely to become more frequent and even more intense.

An Urban Vulnerability Crisis

Nearly half of Pakistan’s 96.4 million urban residents live in informal settlements, many perched on riverbanks, drainage basins, or dry riverbeds. These areas are particularly exposed to flash floods. Homes, often built with mud and rice husk, are no match for the force of monsoon waters.

Weak enforcement of building codes, unchecked construction in flood zones and deforestation have amplified the scale of damage, especially in Punjab’s major cities.

“The scale of devastation is as much about where and how people live as it is about the rain itself,” said one of the study’s co-authors. “Climate change is the accelerant, but poor planning is the fuel.”

Adaptation Imperatives

The WWA report urges Pakistan to prioritise adaptation measures alongside recovery efforts. These include:

• Nature-based solutions such as reforestation and wetland restoration to absorb floodwaters.
• Stricter land-use planning to prevent construction in high-risk areas.
• Improved early warning systems and evacuation protocols to move people out of danger before floods hit.

Following the 2022 floods, the country estimated its adaptation needs at US$152 billion for 2023–2030. Yet most of this remains unfunded. The gap is not just financial but institutional, with disaster resilience often sidelined in urban development.

Rainfall Map Highlights Extreme Saturation

Satellite and ground measurements from June 24 to July 23 show rainfall accumulations of up to 688 mm in some parts of Punjab and Khyber Pakhtunkhwa. The highest concentrations, depicted in dark blue on WWA’s rainfall map, coincide with areas that suffered the highest casualties and housing losses.

With the monsoon season ongoing, NDMA officials warn the figures for deaths and damage may yet rise. Communities downstream of swollen rivers are on high alert for evacuation orders.

A Regional Red Flag

The WWA findings echo warnings from the Intergovernmental Panel on Climate Change, which has consistently projected an increase in heavy monsoon rainfall for South Asia. Pakistan’s combination of rapid urbanisation, fragile housing and climate-driven intensification of extreme weather makes it one of the world’s most at-risk nations.

“The floods of 2025 are not an anomaly,” the report concludes. “They are a signal of the climate we now live in – and the future we must prepare for.”

For Pakistan, the challenge now is twofold: to address the immediate humanitarian needs of thousands of displaced people, and to commit to the long-term infrastructure, environmental and policy changes needed to withstand the storms of a warming world.

As one Rawalpindi emergency official put it: “Climate change is rewriting the rules of our monsoon. If we don’t adapt, the floods will keep coming – and the cost will only rise.”