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GLACIATION Bob Carson June 2007 Spitsbergen photo by Ben Schupack
GLACIATIONBob Carson
June 2007
Spitsbergen photo by Ben Schupack
SNOW
GRAUPEL
American Scientist
SNOWFIELDSARE NOT GLACIERS
MOUNT ST. HELENS 17 MAY 2007
Photo by Jonathan Loeffler
GLACIERS
MOUNT OLYMPUS
MOUNT HAYES, ALASKA RANGE, AUSTIN POST
GLACIER VELOCITY
STAGNANT: TOO THIN OR SURFACE SLOPE TOO GENTLE
POLAR (COLD-BASED): FLOW ONLY (FROZEN TO BED)
TEMPERATE (WARM-BASED): FLOW AND SLIP
SURGING: MELTWATER REDUCES FRICTION
GLACIER BAY
STAGNANT GLACIER
MOUNT EVEREST
POLAR GLACIER
Antarctica photo by Clare Carson
TEMPERATE GLACIER
MOUNT OLYMPUS
THE SOLE OF A GLACIER
SOUTH SAWYER GLACIER, AUSTIN POST
SURGING GLACIER
ST. ELIAS MOUNTAINS
PETERS GLACIER PHOTO BY PAUL SHEARER
30-60% of Svalbard glaciers surge
Fridtjofbreen, Bellsund, Spitsbergen Photo M. J. Hambrey
GLACIER MASS BALANCE
• ACCUMULATION > ABLATION: MARGIN ADVANCES
• ACCUMULATION = ABLATION: EQUILIBRIUM (MORAINE BUILDING)
• ACCUMULATION < ABLATION: MARGIN RETREATS (GLACIER DOES NOT DEFY GRAVITY)
SOUTH CASCADE GLACIER, 1957,
AUSTIN POST
THE EARTH’S NEWEST GLACIER IS
ADVANCING
MOUNT ST. HELENS, 17 MAY 2007
GLACIER IN EQUIBRIUM in mid 1800s
Athabasca Glacier by Ward’s
MOST OF THE EARTH’S GLACIERS ARE RETREATING
TIERRA DEL FUEGO
GLACIER SIZE AND SHAPE
Spitsbergen photo by Ben Schupack
CIRQUE GLACIERS AND CIRQUES
TETON RANGE
CIRQUES
HANGAY MOUNTAINS
TARNS
Katahdin photo by Tim Wood
VALLEY GLACIERS AND GLACIAL TROUGHS
ALTAI MOUNTAINS
GLACIAL TROUGHS
ALTAI MOUNTAINS STEENS MOUNTAIN
GLACIAL TROUGH LAKES
Sierra Nevada photo by Steve BrownWATERTON LAKE
FJORDS
Baffin Island photo by Taylor Johnson
FJORDS
www.kingsleighinn.com/images/SomesSound
WHY ARE FJORDS SO DEEP?
• SEA LEVEL FLUCTUATION = 120 m
• DENSITY ice = 90% DENSITY water
TRACY ARM, AUSTIN POST
folk.uio.no
www.caingram.info
SOGNE FJORD 1308m
www.rosssea.info Skelton Glacier
SKELTON INLET 1933m
MOUNTAIN ICE CAPS
http://www3.eou.edu/geology/wallowalake
Glacier
MOUNTAIN ICE SHEETS
MOUNTAIN ICE
SHEETS
geoscape.nrcan.gc.ca/.../images
WATERVILLE PLATEAU
LAKE CHELAN
CONTINENTAL ICE SHEETS
www.crystalinks.com/antarctica_satellite
CONTINENTAL ICE SHEETS
Greenland photo by George Linkletter
Greenland photo by Art Rempel
Greenland photo by George Linkletter
LARSON ICE SHELFCOLLAPSED IN 1995
svs.gsfc.nasa.gov/vis/a000000/a001400/a001400/
1992 1997
SEA ICE (NOT A GLACIER)
Antarctica photo by Seth White
SEA ICE
Scott Polar Research Institute
ICEBERGS (NOT GLACIERS)
GREENLAND
ICEBERGS
Antarctica photo by Clare Carson
PROCESSES• ICE: ABRASION, PLUCKING,
DEPOSITION
• MELTWATER: CORRASION, ABRASION, DEPOSITION
• MASS WASTING
MOUNT EVEREST
OTHER EROSIONAL LANDFORMS
BEARTOOTH MOUNTAINS
POLISH
VANCOUVER ISLAND
STRIATIONS
LAKE CHELAN
GROOVES
VANCOUVER ISLAND
ROCHES MOUTONEES
BEARTOOTH MOUNTAINS
ARETES
WALLOWA MOUNTAINS
HORNS
ABSAROKA MOUNTAINS
COLS
TETON RANGE
HANGING VALLEYS & TRUNCATED SPURS
BEARTOOTH MOUNTAINS
GLACIER DEPOSITION
FRANZ JOSEF GLACIER
TILL
PUGET LOWLAND
MORAINES
MOUNT EVEREST
TERMINAL MORAINES
LATERAL MORAINES
MEDIAL MORAINES
Denali photo by George Stephens
ALTAI MOUNTAINS
ICE STAGNATION LANDFORMS
RONGBUK GLACIER
KETTLES
MOUNT RAINIER
ESKERS
WATERVILLE PLATEAU
FRANZ JOSEF GLACIER
KAMESMENDENHALL GLACIER
MELTWATER
EMMONS GLACIER
OUTWASH
PUGET LOWLAND
OUTWASH PLAIN
EMMONS GLACIER
PAYETTE LAKE
GLACIER EXTENT 18-20,000 YEARS AGO
images.encarta.msn.com
NORTHWEST EUROPE GLACIATION 18-20,000 YEARS AGO
SVENDSEN ET AL. 2004
GLACIER EXTENT TODAY
THANK YOU!BEN SHUPACK
WHITMAN ’07 ON SPITSBERGEN
