Melting glaciers

Next Alaska's melting glaciers Photographs taken at the same locations decades apart reveal just how dramatically Alaska's glaciers are melting and retreating. Scientists from the University of Alaska and the U. Geological Survey estimate that Alaska is losing ice at the rate of 75 billion metric tons a year. They calculate that Alaska's glaciers and frozen rivers are melting fast enough to cover the whole state with 30 centimeters of water nearly a foot every seven years.

Melting glaciers

Glaciers around the world are melting, retreating and even vanishing altogether. If anything, some are expanding.

Now, scientists have found an explanation for this mysterious glacial stability. While precipitation is increasing across the Himalayas, most of this moisture drops in the summer — except in Karakoram, where snow dominates the scene. A Gallery of Awe-Inspiring Glaciers ] "This gives a reasoning for why you can have increased snowfall in a region and have increased glaciers or stable glaciers in a warming world ," Kapnick told Live Science.

Unusual ice The Karakoram is a picturesque chain of snowy peaks along the border of India, Pakistan and China.

Yet observations in the Karakoram region reveal that the glaciers there are stable, and snowfall is increasing instead of decreasing. She and her colleagues collected data on recent precipitation and temperatures from the Pakistan Meteorological Department and other sources, including satellite data.

They combined this information with climate models to track changes in three regions of the Himalayas between and The researchers found that a new model that simulates climate down to an area of square miles 2, square kilometers was able to match the observed temperature and precipitation cycles seen in the Karakoram.

A model used by the Intergovernmental Panel on Climate Change IPCC to simulate what will happen if the world continues to emit greenhouse gases at current rates was unable to capture these seasonal cycles, Kapnick said.

Melting glaciers

The reason, she said, is that the IPCC and other climate models are lower-resolution, capturing climate change over areas no finer than about 17, square miles 44, square km. The coarser resolution "smoothes out" variations in elevation, which works fine for the central Himalayas and southeast Himalayas.

However, the Karakoram region has more elevation variability than the other two regions. Ultimately, the result is that the IPCC and other models overestimate the amount of warmth in this region, Kapnick said. Winter weather Because previous models overestimated the temperature of the Karakoram, they also underestimated the amount of snow in the region.

This is the crux of the mysterious Karakoram anomaly, the researchers report today Oct. As the globe warms, precipitation increases across the Himalayas. In contrast, the central and southeast Himalayan regions get most of their moisture from monsoons in the summer.

Melting glaciers

Because summer is warmer, most of this precipitation falls as rain. Kapnick and her team found that the snow in Karakoram is likely to persist through at least Understanding the snowfall in the Karakoram and the rest of the Himalayas is important for teasing out regional variations in climate change, but the findings have a more immediate use as well.

Snow acts as a water reservoir for the people in the Himalayan region, so seasonal precipitation predictions are important for understanding water availability.

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If snow and ice melt too quickly, Kapnick said, it can cause devastating floods. This article was updated to correct the resolution of the model used by the researchers. Original article on Live Science.These glaciers in the Himalaya Mountains of Bhutan have been receding over the past few decades, and lakes have formed on the surfaces and near the .

Before-and-after photos illustrate the rapid and dramatic melting of Alaska's glaciersFounded: Sep 18, All of the phases of water—solid, liquid and vapor—relate to glacier dynamics. Water has unique qualities that come into play in understanding the .

Sep 21,  · Building walls on the seafloor could prevent glaciers from melting and sea levels rising due to global warming, scientists say. Glaciers in Alaska's Denali National Park are melting faster than at any time in the past four centuries because of rising summer temperatures, a new study finds.

New ice cores taken from the. Glaciers around the world are melting, retreating and even vanishing altogether. But in the mountainous Karakoram region of Asia — home to K2, the second-highest peak on .

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