There are remarkable regional differences in glacier change in south-western China, according to a study published in Environmental Research Letters (ERL). The authors, from China, the UK and Canada, believe these variations could be due to differences in precipitation and temperature, as well as the location, scale and frontal altitude of the glaciers.

South-western China is home to almost 30 000 square kilometres of glaciers. Zongxing Li of the Chinese Academy of Sciences in Lanzhou and his colleagues examined data on the response of some of these glaciers to changes in temperature and precipitation between 1961 and 2008.

“We found that, while some glaciers have retreated, others, such as those in the Gangrigabu Mountains, are advancing,” Li told environmentalresearchweb. “We were also surprised to find a significant relationship between temperature rise in the region and sea-surface temperature in the western Pacific.”

One example in particular highlights the differences that Li and his colleagues found. The Hengduan Mountains and Gangrigabu Mountains are both monsoonal-temperate glacial regions where temperature and precipitation increased in the studied period. Both regions are located on the south-eastern Tibetan plateau. But while the Hengduan Mountains saw significant glacial ablation and retreat, a considerable number of glaciers in the Gangrigabu Mountains advanced.

The researchers state that it is difficult to derive a relationship between climate change and glacier behaviour in south-western China because of the limited observational data available and the complexity of climate change and glacier dynamic response.

However, Li told environmentalresearchweb: “In our study, glacier areas in seven basins of the Himalayas have retreated between 1970s and 2000s, but we do not think all glaciers are retreating. Other research has suggested that debris-covered glaciers with stagnant flow-gradient terminus regions typically have stable fronts in this region. I believe most glaciers in the region will hold in the future owing to fluctuating climate change.”