Glacial Erosion

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Date: 2017
Climate Change: An Encyclopedia of Science, Society, and Solutions
From: Climate Change: An Encyclopedia of Science, Society, and Solutions(Vol. 2: Weather and Global Warming. )
Publisher: ABC-Clio
Document Type: Topic overview
Pages: 5
Content Level: (Level 5)

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Page 167

Glacial Erosion

Rising temperatures have been melting ancient glaciers on the high Alps, causing devastating summer rockslides that have endangered the lives of many climbers, including 70 on July 14, 2003, which required one of the largest mass rescues in the area’s history. Most climbers were plucked from the Matterhorn, which was racked by two major landslides that day. According to one observer, “Those climbing its slopes could have been forgiven for thinking the crown jewel of the Alps had started falling apart under their feet” ( McKie 2003 ).

According to Robin McKie, writing in The Observer in London, “The great mountain range’s icy crust of permafrost, which holds its stone pillars and rock faces together, and into which its cable car stations and pylons are rooted, is disappearing” ( McKie 2003 ). Several recent Alpine disasters, including the avalanches that killed more than 50 people at the Austrian resort of Galtur during 1999, have been blamed on melting permafrost. During August 2003, the freezing level in the Alps Page 168  |  Top of Articlerose to 13,860 feet (4,200 meters), almost 4,000 feet above its usual summer maximum of 3,000 meters (9,900 feet) ( Capella 2003 ).

Roughly half of the recent Alpine ice erosion can be attributed to natural climate change, according to a study. “This doesn’t question the actuality, and the seriousness, of man-made climate change in any way,” said Matthias Huss, a University of Fribourg (Switzerland) glaciologist who led the study. “But what we do see is that current glacier retreat might be due to natural climate variations as it is to anthropogenic greenhouse warming” ( Schiermeier 2010 ). Among the natural changes may be a 60-year cycle called the Atlantic Multidecadal Oscillation (AMO) that affects ocean circulation and temperatures. In 100-plus years (1910 to the present), 30 glaciers in the Swiss Alps monitored in this study lost half their mass on average. Changes in the AMO in the 1910s and 1970s produced small mass gains. The rest of the time, the AMO cycle has worked together with human greenhouse gas emissions to erode the glaciers’ mass. The human role has accelerated over time, Huss said.

More Danger Ahead

Scientists attending the 2003 International Permafrost Association conference in Zurich, Switzerland, said that conditions in the high Alps could get more dangerous in coming years, assuming continued warming. “I am quite sure what happened on the Matterhorn … was the result of the Alps losing its permafrost. We have found that the ground temperature in the Alps around the Matterhorn has risen considerably over the past decade. The ice that holds mountain slopes and rock faces together is simply disappearing. At this rate, it will vanish completely—with profound consequences,” said civil engineer Professor Michael Davies of Dundee University and a conference organizer ( McKie 2003 ).

Air-temperature increases in the Alps are being amplified fivefold underground. A borehole dug at Murtel in southern Switzerland has revealed that frozen subsurface soils have warmed by more than 1°C since 1990. In addition to general air-temperature rises that are heating the ground, increased evaporation caused by warmer summers also has caused heavier snows that insulate the soil and keep it warmer in winter. Ice also becomes more unstable as it warms, raising the danger of devastating landslides.

Melting permafrost in the Alps and other European mountain ranges does much more than spoil mountain climbers’ treks. Landslides sometimes threaten alpine villages and ski resorts. Fear has been expressed that some villages may have to be abandoned. Rivers also may be blocked by debris, causing flash floods when these unstable mounds of earth subsequently collapse. According to a report in the The Guardian (U.K.), Charles Harris of the earth sciences department at Cardiff University, who coordinates research for the European Union, said that the main areas at risk are the Alps in Switzerland, Austria, France, Germany, and Italy, where the mountains are densely populated and the slopes are especially steep. According to this account, among the places being monitored is the Murtel-Corvatsch mountain above fashionable St. Moritz, and the Schilthorn, which towers above the Muran and Gandeg resorts near Zermatt ( Brown 2001 ). Harris said that the Swiss Alps had warmed by 0.5°C to 1.0°C since the mid-1980s ( Clover 2001 ).

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Melting Glaciers Yield Baskets, Arrows, and Mummies

As temperatures warm and glaciers melt, some of the world’s highest mountains are yielding mummies, skeletons, pieces of old aircraft, and many other things—so much so and in such wild variety that a new academic field has organized with its own periodical, The Journal of Glacial Archaeology. Publication editor and University of New Mexico anthropologist E. James Dixon professes a sense of urgency to catalog findings before they decompose in warming air. “For every discovery that is made, there are thousands coming out of the ice and are decomposing very rapidly,” Dixon said. “In the ice, some of the most delicate artifacts are preserved. We’ve found baskets, arrow shafts with the feathers intact and arrowheads and lashings perfectly preserved” ( Johnson 2015 ).

Anthropologists and archaeologists are finding more than old baskets and arrow shafts. Tim Johnson of McClatchy Newspapers reported that Mexico’s tallest volcano, Pico de Orizaba, North America’s third highest peak at 18,491 feet, is “performing an all-natural striptease,” yielding the corpses of climbers who died in attempts to ascend its slopes.

“Late in February [2015],” reported Johnson, “a climbing party circled the jagged crater atop Orizaba. One of them slipped, and they later said he skidded down and came to a stop. When he got up, he saw a head poking out of the snow,” said Hilario Aguilar Aguilar, a veteran climber. It was a mummified climber, a member of a Mexican expedition hit by an avalanche in November 1959. Some climbers fell near the Chimicheco Ridge, their bodies frozen in an icy time machine, to be discovered more than half a century later ( Johnson 2015 ).

Elsewhere, now-bare Andean slopes have yielded Incan mummies, and mountains in the Canadian Yukon have bared piles of vile-smelling caribou dung that had been frozen for several thousand years. Two German tourists in 1991 nearly stumbled on a 5,300-year-old dummy in the Italian Alps that came to be known as Otzi the Iceman, who may have been a shepherd.

Further Reading

Johnson, Tim. “As Globe Warms, Melting Glaciers Revealing More Than Bare Earth.” McClatchy Newspapers, June 19, 2015. .

An organization called Permafrost and Climate in Europe (PACE) monitors the effects of climate change on the stability of mountains. As PACE literature contends, “The combination of ground temperatures only slightly below the freezing point, [along with] high ice contents and steep slopes, makes mountain permafrost particularly vulnerable to even small climate changes” ( Brown 2001 ).

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Flood Threats below the Alps

Melting glacial ice has been increasing the volume of the Rhine, Rhone, and Po rivers. Since 1850, the volume of Europe’s glaciers has shrunk by 50 percent ( Toner 2002 ). The great rivers of Europe that rise in the Alps may decline from swollen summer torrents to trickles as global warming melts ancient mountain ice fields during the 21st century. David Collins of Salford University presented findings to a Royal Geographical Society conference in Belfast that indicate that the ice now melting in the Alps accumulated during the Little Ice Age between the 15th and 18th centuries.

“The [present] combination of warmer summers and drier winters, meaning less snow to feed the glaciers, has meant that the vast bank of ice on the mountain tops is disappearing,” said Collins. “The ice is like money in the bank, if you keep drawing more than you put in, eventually it runs out” ( Brown 2002 ). Before the rivers dry up, warming will supply a final torrent as the glaciers melt. The summer flows of the rivers fed from the Alps, including the Rhine, Rhone, Po, and Inn (which feeds into the Danube) recently have been higher than they have been for centuries. The excessive water flow has been good news for those living on riverbanks in southern and Eastern Europe who drew off the excess water for irrigation and domestic use. In France, the river water was used to cool nuclear power stations.

Forecasts by Collins and his team showed that these boom times for water supply may soon end. When all the ice goes, the summer flow of the rivers will be almost entirely dependent on rainfall. Under some climate models, rainfall in southern Europe probably will decline under warmer conditions. “We can see serious potential problems but it is very hard to be precise because weather patterns could change again,” he said ( Brown 2002 ).

“Some of the glaciers—for example, there are a number of small ones at Gornergrat, near Zermatt—are now below the snow line in summer. This means they are doomed. The ice they are made of was laid down in snowfall two or three centuries ago and is melting away faster each year,” Collins reported ( Brown 2002 ). Collins said the reduction in the glaciers in the Alps had been matched by an increase in glacier size in the Jotunheimen range in Norway because of increased precipitation in northern Europe—in this case, falling as snow—had blanketed those glaciers and protected them from any temperature increase. This had led to a net increase in the size of glaciers over the same period as those in the Alps were retreating.

The people of Macugnaga (pronounced maa-COON-yaga), an Italian Alpine resort village, long ago learned to cope with the floods that sometimes accompany the melting snow in the spring. “But nothing,” according to on account, “prepared them for the catastrophic flood threat they now face—a glacier rapidly melting from unusually warm temperatures” ( Konviser 2002 ).

During July 2002, as many as 300 officials and volunteers struggled under a state of emergency “to prevent a gigantic glacier-fed lake from breaking through the giant ice wall that confines it” ( Konviser 2002 ). If they failed, a devastating wall of water carrying chunks of glacier and mountainside could surge through this verdant valley. Known technically as a glacier lake outburst flood, “it’s an event previously seen Page 171  |  Top of Articleonly in the Himalayas where the slopes of the mountains are steeper. But scientists say the threat is both real, and a warning of things to come if the global-warming trend continues” ( Konviser 2002 ).

“It’s a dangerous situation because the border of the lake is ice, which isn’t stable,” said Claudia Smiraglia, a professor of physical geography at Milan University. “The glacier is always in motion” ( Konviser 2002 ). Reporting for the Boston Globe, Bruce I. Konviser described the potential scope of the threat:

If the water escapes, the 650 residents of Macugnaga and as many as 7,000 vacationers, depending on the time of year—would have approximately 40 minutes to gather their belongings and get to higher ground before the wave of water and mountain wipes out [many], if not all, of the manmade structures, according to Luka Spoletini, a spokesman for the Italian government’s Department of Civil Protection. ( Konviser 2002 )

Further Reading

Brown, Paul. “Melting Permafrost Threatens Alps; Communities Face Devastating Landslides from Unstable Mountain Ranges.” The Guardian (U.K.), January 4, 2001, 3.

Brown, Paul. “Geographers’ Conference: Ice Field Loss Puts Alpine Rivers at Risk: Global Warming Warning to Europe.” The Guardian (U.K.), January 5, 2002, 9.

Capella, Peter. “Europe’s Alps Crumbling; Glaciers Melting in Heat Wave.” Agence France Presse, August 7, 2003 (LEXIS).

Clover, Charles. “Geographers’ Conference: Alps May Crumble as Permafrost Melts.” Telegraph (London), January 4, 2001, 12.

Konviser, Bruce I. “Glacier Lake Puts Global Warming on the Map.” Boston Globe, July 16, 2002, C1.

McKie, Robin. “Decades of Devastation Ahead as Global Warming Melts the Alps: A Mountain of Trouble as Matterhorn Is Rocked by Avalanches.” The Observer (London), July 20, 2003, 18.

Schiermeier, Quirin. “Glaciers’ Wane Not All Down to Humans.” Nature 465 (June 10, 2010): 677.

Toner, Mike. “Meltdown in Montana; Scientists Fear Park’s Glaciers May Disappear within 30 Years.” Atlanta Journal-Constitution, June 30, 2002, 4A.

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Gale Document Number: GALE|CX7352100080