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THE GLACIER

THE GLACIER. A glacier is a mass of ice that is formed on land in consequence of the compaction and recrystallization of snow. What is the glacier?. The snow turns. Snowflakes. Granular snow. Firn. Compact ice. Glacial metamorphism.

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THE GLACIER

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  1. THE GLACIER

  2. A glacier is a mass of ice that is formed on land in consequence of the compaction and recrystallization of snow What is the glacier?

  3. The snow turns Snowflakes Granular snow Firn Compact ice

  4. Glacial metamorphism

  5. The transformation of snow into ice is a slow process, which also requires hundreds of years The pressure of the snow that accumulates annually determines the compaction of the underlying material, with the removal of most of the air and increasing the size of the ice crystals Part of the air is trapped in the form of bubbles which progressively reduce in size to dissolve in the ice, which assumes a typical blue color (ice blue) Snow Snowcapped Ice

  6. The world's glaciers Distribution of ice on the surface of the earth: in dark blue caps, black platforms, clear blue sea ice, mountain glaciers in blue

  7. The world's glaciers Greenland (7.5%) Ice remaining (0.5%) Antarctica (92%)

  8. The Glacier of Europe - 38 % Pyrenees and Mediterranean -12% Alps -11% Island - Svalbard

  9. The limit of permanent snow

  10. The continental glaciers Also referred to as Norwegian islands Constitute 99% of all glaciers

  11. Antarctic ice sheet The largest single mass of ice on Earth One part covers the continent, another floats on the sea (glacialplatform)

  12. Antarctic ice sheet The ice flows from the ice caps to a series of platforms floating on the sea ice Beneath the Antarctic ice sheet are mountain ranges

  13. Antarctica seen from satellite

  14. The complete melting of Antarctic ice would lead to a sea level rise of about 70 meters

  15. Continental glacier Arctic Unlike Antarctica, consisting of a perennially ice-covered continental plateau and surrounded by the oceans, the Arctic, for most of its length, is formed by a sea (the Arctic Ocean), which occupies the central part of the region

  16. Polar ice Formed from solidifiedseawater The largest ice shelves are located in the Arctic Ocean around the Arctic and around Antarctica

  17. Mountain glaciers Monte Ruitor - Valle d'Aosta Pizzo Bernina - Svizzera

  18. Aletsch - Svizzera Gorner – Monte Rosa

  19. Valtellina- Ghiacciao dei Forni

  20. The part of glacier -Collector basin: area in which there is the accumulation of snow. The very existence of a glacier depends on the difference between the power supply and ablation, the amount of ice lost by melting or sublimation

  21. THE MOVEMENT

  22. Different velocity

  23. Crevasses and seracs

  24. Alpine glaciers retreat Reduction of the glacier Present under the big UJA Ciardoney of the Gran Paradiso   • The ice in 1930 and today

  25. The thickness of the Alpine glaciers decreased in a few decades of 14 meters, three of which only the last hot summer 2003. The glaciers have actually started to decline since 1850 (the end of the so-called "Little Ice Age" that lasted for 250 years), but in recent decades have begun to melt at an unprecedented rate

  26. The "sad" view of the glacier Ciardoney after the hot summer 2003, which has significantly reduced the thickness of the ice. Completely free of residual snow, blackened debris, and it is exposed to strong merger

  27. MEASURES AT THE END OF SUMMER 2012 IN GLACIER Ciardoney: ANOTHER SEASON OF IMPOSING REDRESS At the end of a summer extraordinarily hot (in third place in Turin from 1753), the entire glacier appeared devoid of residual snow. The findings showed again a considerable loss of mass, equal to a water blade average of 2.16 m, while the front has retreated by 20 m

  28. Les bediéres

  29. 10.09.2007: the numerous boulders tumbled down the glacier from the north wall UJA of the Little Ciardoney, a phenomenon more and more important with the deglaciation of the slopes.

  30. The frontal area of the glacier Basei view the 02.09.2003 (left) and the 01.09.2007 (right). You sense the net loss of thickness and the emergence of bedrock in the western (right in photo).

  31. Two large boulders metric sizes precipitate in the right-front in August 2007, obvious effect of deglaciation on the rocky bar above. In the background to the right, the Gran Paradiso and Ciarforon

  32. The glacier Basei viewed from the north, almost completely devoid of snow residua limitata a few benches in the basin at the summit. Clearly visible the morainal century.

  33. The current phase of withdrawal is the continuation of a phase 'hot' already in place or the upward trend in temperature is due to the industrial development started just 150 years ago.

  34. We live in a hot phase "natural", but human activities, in particular the use of fossil fuels that produce carbon dioxide and favor the '' greenhouse effect ', have helped to increase global warming.

  35. The rate of melting of glaciers has tripled since the seventies onwards, and especially after the mid-eighties. From 1850 onwards, the total volume decreased two-thirds.

  36. Twenty years from the glaciers could be just a memory. The highest peaks of the Alps, at the end of the twenty-first century, will appear as a barren expanse of gravel and stones.

  37. Sea of Ice .

  38. The sea of Ice is a glacier located on the northen slopes of the Mont Blanc massif, in the Alps.At 7 km long and 200 metres deep, it is the longest glacier in France.

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