GLACIATION Bob Carson June 2007
Spitsbergen photo by Ben Schupack GRAUPEL
SNOW American Scientist SNOWFIELDS ARE 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
WATERTON LAKE Sierra Nevada photo by Steve Brown 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 SOGNE FJORD 1308m
www.caingram.info
folk.uio.no SKELTON INLET 1933m
Skelton Glacier www.rosssea.info MOUNTAIN ICE CAPS
Glacier
http://www3.eou.edu/geology/wallowalake MOUNTAIN ICE SHEETS MOUNTAIN ICE SHEETS
WATERVILLE PLATEAU
geoscape.nrcan.gc.ca/.../images LAKE CHELAN CONTINENTAL ICE SHEETS
www.crystalinks.com/antarctica_satellite Greenland photo by George Linkletter
Greenland photo by Art Rempel
CONTINENTAL ICE SHEETS
Greenland photo by George Linkletter ICE SHELVES
ROSS ICE SHELF www.mbari.org/benthic/tour1.htm LARSON ICE SHELF COLLAPSED IN 1995
1992 1997
svs.gsfc.nasa.gov/vis/a000000/a001400/a001400/ 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
FRANZ JOSEF GLACIER
WATERVILLE PLATEAU KAMES MENDENHALL 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 BEN SHUPACK WHITMAN ’07 THANK YOU! ON SPITSBERGEN