CLIMATE CHANGE IN ARCTIC AND ALPINE AREAS 1. Introduction 2. Data sources: glaciers 3. Data sources: ice cores 4. Patterns and mechanisms 5. Feedbacks and surprises
Striations (evidence of glacial erosion)
U-shaped valley (evidence of glacial erosion)
Glacial moraines (evidence of glacial depositional)
Glacier retreat above Manang, Nepal- 1989.
Holgate Glacier, Alaska, 1909. Source: National Snow and Ice Data Center glacier rephotography collection.
Holgate Glacier, Alaska, 2004. Source: National Snow and Ice Data Center glacier rephotography collection.
McCall Glacier, Alaska, 1958. Source: National Snow and Ice Data Center glacier rephotography collection.
McCall Glacier, Alaska, 2003. Source: National Snow and Ice Data Center glacier rephotography collection.
Franz Josef Glacier, New Zealand, 1951 Source: National Snow and Ice Data Center glacier rephotography collection.
Franz Josef Glacier, 1952 Source: National Snow and Ice Data Center glacier rephotography collection.
1954 Source: National Snow and Ice Data Center glacier rephotography collection.
1956 Source: National Snow and Ice Data Center glacier rephotography collection.
1957 Source: National Snow and Ice Data Center glacier rephotography collection.
1958 Source: National Snow and Ice Data Center glacier rephotography collection.
1960 Source: National Snow and Ice Data Center glacier rephotography collection.
1961 Source: National Snow and Ice Data Center glacier rephotography collection.
1964 Source: National Snow and Ice Data Center glacier rephotography collection.
Antarctic ice shelf collapse: Larsen-B ice shelf, 2002
Antarctic ice shelf collapse: Larsen-B ice shelf, 2002
Location of Vostok station, Antarctica. Todd Sowers, Lamont Doherty Earth Observatory/ NOAA Paleoclimatology Program. Source:
Location of Vostok station, Antarctica. Todd Sowers, Lamont Doherty Earth Observatory/ NOAA Paleoclimatology Program. Source:
How ice coring works
OXYGEN ISOTOPE ANALYSIS 8 electrons (-) Nucleus: 8 protons (+) 8 neutrons
OXYGEN-16 ( 16 O): 8 protons, 8 neutrons OXYGEN-18 ( 18 O): 8 protons, 10 neutrons
WHY IS THIS USEFUL FOR CLIMATE RECONSTRUCTION? Fractionation!
Two isotopes of oxygen: 16 O 18 O Which water molecules fall as snow near the poles? H 2 16 O H 2 18 O Which water molecules rain out more easily? Which water molecules evaporate more easily?
Bigger ice sheets separate out the isotopes More 16 O locked up in the ice sheets More 18 O remains in the oceans
Source: Peter Sloss, NOAA/NGDC, NOAA Paleoclimatology Program.
Quelccaya ice cap. Source: Lonnie Thompson, Ohio State University/ NOAA Paleoclimatology Program.
Packing in to the Quelccaya ice cap. Source: Lonnie Thompson, Ohio State University/ NOAA Paleoclimatology Program.
Qori Kalis glacier, Quelccaya ice cap, 1978. Source: Byrd Polar Research Station, Ohio State University.
Qori Kalis glacier, Quelccaya ice cap, 2000. Source: Byrd Polar Research Station, Ohio State University.
Recent behaviour of twenty mountain glaciers worldwide. Source: Oerlemans, 2001.
Tsaa Glacier, Alaska, 2005. Source: Rozell, 2007, Icy Bay Glaciers Get up and Go, Alaska Science Forum, UAF.
Tsaa Glacier, Alaska, 2007. Source: Rozell, 2007, Icy Bay Glaciers Get up and Go, Alaska Science Forum, UAF.
Efforts to keep the Pitztal Glacier (Austria) from melting. Source: National Geographic.
Surface melting on Greenland, 1992 and 2002. Source: Arctic Climate Impact Assessment, 2004.
New melt extent on Greenland, 2005. Source: Koni Steffen.
Change in mass, 2003-2010, cm water. Source: NASA
Source: The Cryosphere Today/NSIDC
Source: The Cryosphere Today/NSIDC
Source: NASA/The New York Times Average minimum 1979-2010
Site of Vostok station, Antarctica. Todd Sowers, Lamont Doherty Earth Observatory/ NOAA Paleoclimatology Program. Source:
The northern hemisphere at 18,000 BP. Source: Christopherson, 2003.
The first Milankovitch cycle: a change in the shape of Earth s orbit around the sun
The second Milankovitch cycle: a change in the angle of tilt of the Earth s axis
The third Milankovitch cycle: a change in the timing of summer
Delta O-18 (per mil) The Last Deglaciation GISP-2 Oxygen Isotope Data WARM -32-34 -36-38 -40-42 -44 COLD -46 35000 30000 25000 20000 15000 10000 5000 0 Years Before Present
Delta O-18 (per mil) The Last Deglaciation Dansgaard-Oeschger Events GISP-2 Oxygen Isotope Data WARM -32-34 -36-38 -40 Younger Dryas -42-44 COLD -46 35000 30000 25000 20000 15000 10000 5000 0 Years Before Present
General temperature trends over Earth s history derived from fossil evidence Growth of large ice sheets possible COLD WARM
WARMER COLDER Climate change over last ~60 million years. (Source: Raymo.) Time before present (million years) 60 50 40 30 20 10 0 ICE SHEETS Temperature estimated from benthic foraminifera ICE FREE
Time (million years BP) Temperature changes over the last 60 million years 60 50 COLDER Cold enough for permanent ice sheets WARMER Too warm for permanent ice sheets 40 30 20 10
Last 1000 years Last 400,000 years COLDER WARMER Last 60 million years WARMER COLDER COLDER WARMER
Carbon dioxide concentration (ppm) Carbon dioxide changes over time Atmospheric CO 2 recorded in the Vostok ice core, Antarctica, and measured at Mauna Loa, HI. Years before present Source: data from WDC Paleoclimatology and NOAA Mauna Loa CO 2 records.
Preindustrial and anthropogenic carbon dioxide. Source: Ruddiman, 2001, p. 396.
Atmospheric carbon dioxide concentration recorded at Mauna Loa, Hawaii
Atmospheric carbon dioxide concentrations over the last 1000 years. Source: IPCC, 1996.
Source: Arctic Climate Impact Assessment, 2004.
The Arctic is warming at twice the global rate. Source: Arctic Climate Impact Assessment, 2004.
Temperature changes for 2021-2050 relative to 1961-1990. Source: IPCC, 2001. Degrees Celsius
Temperature changes for 2071-2100 relative to 1961-1990. Source: IPCC, 2001. Degrees Celsius
Changing sea ice extent derived from satellite images, 1979-2003. Source: NASA and The New York Times. 1979 2003
Source: NOAA/GFDL Visualization Gallery.
Last 1000 years COLDER WARMER Last 400,000 years WARMER COLDER Last 60 million years COLDER WARMER Too warm for permanent ice sheets Cold enough for permanent ice sheets