OSLO, Dec. 4 (Xinhua) -- Latest figures from the Norwegian Water Resources and Energy Directorate (NVE) showed that 21 of country's glaciers have retreated this year and only one has spread, newspaper Aftenposten reported Monday.
NVE makes annually so-called front measurements of some of Norway's 2,534 glaciers, which show the movements in the mass balance -- the amount of snow that has fallen on the glacier during the winter and how much snow and ice melt away during the summer.
Out of total 31 measured glaciers, 21 have retreated and nine remained unchanged, the report said.
Only Svelgabreen glacier in the western county of Hordaland showed a slight progress, it said.
"I really do not have any good explanation for this, but just this glacier is a little different than the others. It is thick and oblique, and there is a lot of rainfall in this area," said Hallgeir Elvehoy, NVE's senior engineer.
"In recent years we have seen that autumn has become longer, and then winter gets shorter. Then we get less snow and more snow melting," Elvehoy said.
The biggest retreat of 54 meters was measured in the area of the glacier Nigardsbreen in western Luster municipality.
"Hot summer is the worst for the glaciers. It is less important whether it rains. There is little heat in the rain, but if there is hot air blowing over the glaciers, this contributes to increased snow melting," Elvehoy explained.
According to the NVE, many glaciers experienced a growth period in the 1990s.
Since 2000, however, all the glaciers decreased.