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GLACIERS. The DDTeam (Daniela and Daniel). DYN-CLIMATE VAR & CLIMATE CHG. 1/10 of the Earth‘s surface is covered with glaciers Continental glaciers: Antarctica, Greenland Alpine/Mountain glaciers: Valley glaciers (Alps)
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GLACIERS The DDTeam (Daniela and Daniel) DYN-CLIMATE VAR & CLIMATE CHG
1/10 of the Earth‘s surface is covered with glaciers Continental glaciers: Antarctica, Greenland Alpine/Mountain glaciers: Valley glaciers (Alps) Ice caps over mountains and Plateau glaciers (South America, Himalaya, Iceland, Alaska) Tidewater glaciers (Alaska) GLACIERS
4.808 m 5.128 m (March 2006) ALETSCH GLACIER (Switzerland) MOLINOS GLACIER (Colombia) 1900 1980 • SHRINKING LENGTH 2005 2004
MASS CHANGE • Illustration of mass change of the Grosser Aletschgletscher • Considerable mass change during the last 100 years
MUIR GLACIER, ALASKA 1941/08/13 2004/08/31
MAIN VARIABLES INFLUENCING GLACIERS RETREAT SUNSHINE MEAN TEMPERATURE MAXIMUM TEMPERATURE SURFACE ALBEDO CLOUD COVER GLOBAL WARMING POTENTIAL IMPACTS LOSS OF BIODIVERSITY LOSS OF ENVIRONMENTAL GOODS AND SERVICES DECREASES IN WATER SUPPLY AND BASIN REGULATION HUMAN HEALTH
2.0 mm/yr (1932-1997 ) 0.5 mm/yr (1932-1997 ) 1.9-2.1 mm/yr (1932-1997 ) 0.2 mm/yr (1911-1998 ) PROCESSES RESPONSIBLE FOR GSLR VOLUME INCREASE DUE TO OCEAN WARMING MASS CHANGE, PRIMARILY FROM THE MELTING OF CONTINENTAL ICE Mass change plays a dominant role! 0.5 mm/yr < 0.5 mm/yr ? DIRECT ESTIMATES FROM TIDE GAUGES GSLR = 1.5-2.0 mm/yr Oceans are freshening at a rate equivalent to the addition of 1.4 mm/yr of fresh water DYNAMIC HEIGHTS (reflect only volume changes) GAUGE RECORDS
TAKE HOME POINTS GLACIERS AND ICE SHEETS ARE LOCATED IN POLAR REGIONS AND HIGH ALTITUDE AREAS GLACIERS ALL OVER THE WORLD ARE IN A PROCESS OF ACCELERATED MELTDOWN, WHICH CAN BE ATTRIBUTED TO HUMAN ACTIVITIES CONSEQUENCES OF CONTINENTAL GLACIAL MELTING INCLUDE SEA LEVEL RISE AND LOSS OF MARINE BIODIVERSITY THE MOST SIGNIFICANT EFFECT OF THE RETREAT OF MOUNTAIN GLACIERS IS POSSIBLY THE DRAMATIC LOSS OF ENVIRONMENTAL GOODS AND SERVICES