Across the US west, rising temperatures are causing glaciers to retreat to the point of vanishing. About 300 glaciers have disappeared since the 1960s, with almost all of the rest set to drastically shrink as the climate crisis continues to escalate, a new study has found.<\/p>\n
At the midpoint of the last century more than 1,450 glaciers \u2013 large tongues of ice, snow and rock that move under their own weight and gravity \u2013 were threaded throughout the mountains of the American west, providing cool water for ecosystems and agriculture as they gradually melted.<\/p>\n
Some, in the Sierra Nevada of California, were formed a few thousand years ago while others, such as those in the Pacific north-west, are remnants from even further back in the last ice age, which ended about 11,700 years ago.<\/p>\n
The long stories of these perennial masses of ice are coming to a rapid end, however, due to global heating caused by the burning of fossil fuels. The total area of glaciers in the US west has shrunk by a third since the 1960s, the new research found, with evidence this loss is speeding up as temperatures continue to rise.<\/p>\n
About 300 of these glaciers have functionally disappeared, meaning they have reduced to the size of about two football fields and no longer move. After dominating mountaintops for thousands of years, hundreds of once regal glaciers have been reduced to tiny, sad scraps of ice just within the span of time since the Beatles released their first record.<\/p>\n
\u201cWhen I realized this it was like, \u2018Yikes \u2013 that\u2019s a lot more than I thought,\u2019\u201d said Andrew Fountain, a geographer at Portland State University and lead author of the new study.<\/p>\n
Map of glacier loss in the western US<\/a> Photograph: The Guardian<\/p>\n The US\u2019s largest glaciers are still found in Alaska but Fountain said he wanted to conduct the first proper inventory of the \u201cunloved\u201d glaciers that sit closest to where people live, in the lower 48 states. The new research, published in Proceedings of the National Academy of Sciences<\/a>, used satellite data and aerial photography to chart how glaciers across six western US states have receded.<\/p>\n Smaller, south-facing glaciers have experienced the greatest rates of shrinkage, particularly those at lower elevations of below 9,000ft in the Sierra Nevada and under 6,000ft in the Cascade range, which runs along the Pacific north-west.<\/p>\n But even many of the larger glaciers are set to disappear in the next half century, previous work by Fountain has found<\/a>, with the end of the century likely to see them only existing, in a diminished state, atop the tallest mountains in the west such as Mount Hood and Mount Rainier.<\/p>\n Coleman glacier, located on Mount Baker in Washington. Photographs: James Wilbur Sandison\/National Snow and Ice Data Center; Hassan Basagic\/The Glacier RePhoto Project \u201cThe sad conclusion is that we are seeing signs glacier change is accelerating and I\u2019d say a lot of them will be gone by 2100,\u201d Fountain said. \u201cIn the summertime they are melting more because it\u2019s hotter and in winter they are getting rain instead of snow, which isn\u2019t nourishing them. It\u2019s a double whammy. There\u2019s no good news on this.\u201d<\/p>\n Glaciers are important components of alpine ecosystems and provide some water for agriculture and hydroelectric power in the US west, even if they are remote from where most people live. Still, their retreat has been fast enough to cause a sense of angst among locals, according to Fountain.<\/p>\n \u201cPeople like knowing glaciers are around, they are close to their hearts and it\u2019s worrying to see the mountains look bare,\u201d he said. \u201cThe loss of glaciers is also tangible evidence of a shrinking snowpack, where a lot of drinking water is sourced from, so that is a concern when it comes to drought<\/a> too.\u201d<\/p>\n This problem is not confined to North America. In places such as Europe<\/a> and the Himalayas<\/a>, scientists have documented the decline of glaciers as global heating has intensified, imperiling crops and wildlife.<\/p>\n \u201cWe are turning up the heat in the refrigerator, so the ice is melting everywhere,\u201d Fountain said. The loss of glaciers can be slowed by action to cut planet-heating emissions, he said, but the process of halting or even restoring them could take centuries, if at all.<\/p>\n Until then, glaciers will be at increasing risk of destabilizing in sudden, potentially disastrous ways, such as when a catastrophic glacier and bedrock collapse along the Tibet and Nepal border<\/a> in August killed at least 1,400 people, with thousands more still missing<\/a>.<\/p>\n Mazama glacier, located on Mount Adams in Washington. Photographs: Harry F Reid\/National Snow and Ice Data Center; Hassan Basagic\/The Glacier RePhoto Project \u201cThere is a whole suite of dangers we haven\u2019t quite prepared for which is not just that the ice has gone but that the terrain isn\u2019t stable any more,\u201d said Eric Rignot, a glaciologist at the University of California, Irvine. \u201cWe have seen that in Nepal but also in the Alps, where the climbing season is getting shorter because it\u2019s too dangerous. That is something I\u2019m worried about.\u201d<\/p>\n
\n Composite: James Wilbur Sandison\/National Snow and Ice Data Center; Hassan Basagic\/<\/p>\n
\n Composite: Harry F Reid\/National Snow and Ice Data Center; Hassan Basagic\/The Glacier RePhoto Project<\/p>\n