Islamabad: The Swat River basin in Khyber Pakhtunkhwa could experience a temperature increase of more than 5°C by 2100, raising the risk of floods, erosion and water shortages as glaciers continue to retreat, according to a climate risk assessment released on Wednesday.
The assessment, conducted under the Green Climate Fund's (GCF) Glaciers to Farms programme with support from the Asian Development Bank (ADB), projects changes in rainfall, snowmelt and river flows across the watershed. Temperatures are expected to rise particularly between October and June, while summer rainfall could more than double under some climate scenarios. Winter rainfall, however, is projected to change comparatively little.
The findings indicate that the basin may initially experience increased water availability as rising temperatures accelerate glacier melting. Over time, however, reduced glacier mass is expected to weaken river flows and increase the risk of water shortages.
How will glacier retreat affect Swat?
The assessment identifies more than 10,000 glaciers within the Swat basin, making the watershed dependent on changes in mountain snow and ice. As temperatures rise, melting glaciers and thawing permafrost could destabilise mountain slopes and natural barriers, increasing the risk of landslides, flash floods and glacial lake outburst floods (GLOFs).
These events could threaten roads, bridges, settlements and irrigation systems across Swat and downstream communities.
Changes in rainfall patterns could also intensify soil erosion, damage farmland and affect water quality. The report warns that the combined effects of glacier retreat and changing precipitation could create a period of increased runoff followed by declining water availability.
This would affect communities that depend on glacier fed rivers for agriculture, drinking water, and other economic activities.
Why could more rainfall lead to water shortages?
Although some climate scenarios project higher summer rainfall, the assessment indicates that increased precipitation would not necessarily translate into a reliable water supply. Heavier rainfall over shorter periods can increase runoff and flooding without replenishing water reserves sufficiently for use during drier months.
Glaciers currently help regulate river flows by releasing meltwater during warmer periods, particularly when rainfall is limited. As glacier mass declines, that contribution is expected to weaken, reducing the natural buffer against drought.
Higher temperatures are also projected to increase water demand, particularly for agriculture during summer. The combined effects could place pressure on irrigation systems and agricultural production in areas already vulnerable to changes in seasonal water availability.
Regional assessment examines four river basins
The Swat study forms part of a regional assessment covering four glacier fed watersheds in Central and West Asia. Alongside Swat, researchers examined the Kura basin, spanning Armenia, Azerbaijan and Georgia; the Naryn basin in Kyrgyzstan; and the Pyanj basin, which connects parts of Central Asia and Afghanistan.
The researchers analysed four decades of temperature, rainfall and snowfall records and used multiple climate models to develop projections for 2035, 2055, 2085 and 2100. Across the four basins, temperatures are projected to rise by approximately 3°C to 5°C by the end of the century, affecting water availability, agriculture and settlements.
The assessments are intended to guide the Glaciers to Farms programme, which covers nine developing countries and aims to improve water management and climate adaptation.
What does Pakistan need to address?
The findings underline the need to account for changing river flows and flood risks in the planning of infrastructure, agricultural systems and settlements across northern Pakistan. The assessment identifies watershed management, flood monitoring, early warning systems and climate informed infrastructure planning as measures that could reduce risks.
Improving water storage and irrigation efficiency could also help communities manage the transition from increased glacier runoff to declining water availability. The ADB-supported Glaciers to Farms programme has a proposed financing framework of USD 3.5 billion, including USD 250 million from the Green Climate Fund, to support adaptation across participating countries.
However, the assessment does not specify how much funding will be allocated to the Swat watershed or provide a timeline for individual projects in Pakistan. The projections are not forecasts of a particular flood or drought. They describe how risks could develop under different climate scenarios.
For Pakistan, the findings suggest that planning for both flood protection and long-term water security will be necessary as warming changes the role of glaciers in the country's river systems.
