Home South pole ice Long-term study of Himalayan glaciers – sciencedaily

Long-term study of Himalayan glaciers – sciencedaily

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The glaciers of Nanga Parbat, one of the highest mountains in the world, have shrunk slightly but steadily since the 1930s. This loss of area is evidenced by a long-term study conducted by researchers at the South Asia Institute of l ‘University of Heidelberg. Geographers combined historical photographs, surveys, and topographic maps with current data, allowing them to show glacial changes in this northwestern Himalayan massif as early as the mid-1800s.

Detailed long-term glacier studies that extend the observation period to the period preceding the ubiquitous availability of satellite data are hardly possible in the Himalayan region due to the lack of historical data. As Professor Dr Marcus Nüsser of the Institute of South Asia explains, this is not the case for the Nanga Parbat massif. The earliest documents include sketches and drawings made during a research expedition in 1856. Based on this historical data, Heidelberg researchers reconstructed glacial changes along the southern face of Nanga Parbat. Additionally, there are numerous photographs and topographic maps from rock climbing and scientific expeditions since 1934. Some of these historical photographs were taken in the 1990s and 2010s from identical vantage points for comparison. Satellite images from the 1960s supplemented the database used by Professor Nüsser and his team to create multimedia temporal analysis and quantify changes in glaciers.

The glaciers of Nanga Parbat, fed largely by avalanches of ice and snow, show significantly lower rates of retreat than in other Himalayan regions. One exception is the predominantly snow-covered Rupal Glacier, which has a significantly higher rate of retreat. “Overall, further studies are needed to better understand the particular influence of avalanche activity on glacier dynamics in this extreme high mountain region,” says Professor Nüsser.

Researchers are particularly interested in fluctuations in glaciers, changes in ice volume and the increase in debris-covered areas on the surface of glaciers. Their analyzes covered 63 glaciers already documented in 1934. “Analyzes showed that the area covered with ice has shrunk by about seven percent, and three glaciers have completely disappeared. At the same time, we have identified a significant increase in coverage. debris, ”adds Professor Nüsser. The geographical location of the Nanga Parbat massif in the extreme northwest of the Himalayan arc near the Karakorum range could play a particular role in the relatively moderate retreat of the glaciers. In the phenomenon known as the Karakorum anomaly, no significant glacier retreat has been identified as a result of climate change in this mountain range, unlike anywhere else in the world. “An increase in precipitation at high altitudes may be the reason, but the exact causes are still unknown,” says Professor Nüsser. The researchers speculate that the low ice loss in the Karakorum and Nanga Parbat region may also be due to the protection offered by the massive debris cover and year-round avalanche flow from the steep flanks.

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