New research published today into climate change in Asia could explain why many glaciers there are growing and not melting.

The investigation into the western Himalaya and the surrounding Karakoram and Hindu Kush mountains shows that this area could be reacting differently to global warming, the phenomenon blamed for causing glaciers to melt and shrink.

Researchers at Newcastle University looked at temperature trends in the Upper Indus Basin over the past century.

They found that a recent rise in winter temperatures and a cooling of summer temperatures, combined with an increase in snow and rainfall, could be causing glaciers to grow, at least in the higher mountain regions.

These findings are particularly significant because temperature and rain and snow trends in the Upper Indus Basin also impact on the water availability for more than 50 million Pakistanis.

Melt water from glaciers and the previous winter's snow supplies water for the summer run-off which feeds irrigation both in the mountains and in the plains of the lower Indus.

The vast Indus basin irrigation system is the mainstay of the national economy of Pakistan, which has 170,000 square kilometres of irrigated land, an area two-thirds the size of the UK.

Being able to predict trends could contribute to more effective management of the two major dams in the Upper Indus Basin, the Mangla Dam and the Tarbela Dam, and allow a better long-term control of water for irrigation and power supplies.

These dams have the capacity to produce around 5,000 megawatts of electric power.

The amount of run-off depends on the elaborate interplay of weather conditions.

One third of the run-off, which comes from the higher mountain regions, is largely dependent on the temperature in the summer, research shows.

Specifically, the fall of 1C in mean summer temperature since 1961 is thought to have caused a 20% drop in run-off into the higher mountain rivers.

Yet two-thirds of run-off from the lower mountain regions is dependent on the amount of snow in the previous winter. Heavy winter snowfall is followed by a greater volume of summer run-off.

Dr Hayley Fowler, senior research associate at the school of civil engineering and geosciences at Newcastle University, said: "Very little research of this kind has been carried out in this region and yet the findings from our work have implications for the water supplies of around 50 million people in Pakistan who are dependent on the activity of the glaciers.

"Our research suggests we could be able to predict in advance the volume of summer run-off, which is very useful in planning ahead for water resources and also the output from the dams."

Co-researcher David Archer added: "Our research is concerned with both climate change and the climate variability that is happening from year to year.

"Information on variability is more important for the management of the water system as it will help to forecast the inflow into reservoirs and allow for better planning of water use for irrigation.

"However, information on the impacts of climatic change is important for the longer term management of water resources and to help us understand what is happening in the mountains under global warming."

The findings are published in the American Meteorological Society's Journal of Climate.