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Alaska Conservation Solutions2008
The Greatest Threat
Global Warming: The Greatest Threat 2006 Deborah L. Williams
There is no doubt in my mind that climate change is one of the greatest threats facing humanity today.
Markku Niskala Secretary-General of the Red Cross January 2008
Photo The Age, Melbourne. All rights reserved
The Greatest ThreatThings are getting desperate enough now that we need to throw away our conservatism and just act.Dr. Terry Chapin, University of Alaska Fairbanks
Amanda Byrd/Canadian Ice Service
Global Warming Basics
What do these pollutants do? Global FeverGreenhouse gases make the earth too hot, just like:> sleeping under a heavy blanket in the summertime > wearing a parka that is too thick
Our atmospheric blanket or parka is over 35% thicker than it used to beThinner blanket is just right.
Thicker blanket traps too much heat.
Weather vs. ClimateWeather: The short-term state of the atmosphere -- up to a few days Climate: Long-term averages, frequencies and extremes -- generally 3 to 5 decades
Global Warming: The Greatest Threat 2006 Deborah L. Williams
1950
2008
Choosing shorts or long underwear on a particular day is about weather; the ratio of shorts to long underwear in the drawer is about climate.Charles Wohlforth ~ The Whale and the Supercomputer
Global Warming: The Greatest Threat 2006 Deborah L. Williams
Weather vs. Climate
Climate is what we expect, weather is what we get.
Anchorage, AK January 18, 2009Photo courtesy of Parker Rittgers / ADN reader submission
Mark Twain
Global Warming Basics
Alaska is Ground ZeroChanges in physical and biological systems and Surface surface temperature 1970-2004 Air Temperature Trends 1942-2003
In past 50 years, Alaska:Global Warming: The Greatest Threat 2006 Deborah L. Williams
Temperatures have increased
4oF overall(National Assessment Synthesis Team)
Worldwide:Temperatures have increased slightly more than 1oF(IPCC, 2007) IPCC, 2007
Temperature Change oC 1970-2004Chapman and Walsh, 2004 -1.0 -0.2 0.2 Chapman and Walsh, 2004 1.0 2.0 3.5
Future Temperatures in Alaska
Temperature MeasurementsImpact of La Nina in Last 12 MonthsOcean temperature models predict a warm 2008-2009 winter in Alaska
.
NASA 2008
Global Warming Basics
Why has Alaska warmed the most?The Albedo Effect Snow and sea ice reflect 85-90% of suns energy Ocean surface and dark soil reflect only 10-20%(ACIA, 2004)
Global Warming: The Greatest Threat 2006 Deborah L. Williams
Increased melting of snow and sea ice More dark earth and ocean surface is exposed More of suns heat energy is absorbed
Land or water warms faster
Its like wearing a white shirt v. a black shirt
Global Warming Basics
Why has Alaska warmed the most?Other Factors:(ACIA 2004)
1) Albedo effect 2) More energy goes directly into warming than into evaporation 3) Atmosphere layer is thinner in the Arctic 4) Increased heat transfer from oceans as sea ice retreats
ACIA Graphic
5) Alterations in atmospheric and ocean circulation
Temperature MeasurementsImpact of La Nina in Last 12 MonthsOcean temperature models predict a warm 2008-2009 winter in Alaska
.
NASA 2008
Impacts in Alaska
Impacts of Warming in AlaskaNOAA photo Tony Weyiouanna, Sr Columbia University photo
1. Melting ice, glaciersand permafrostGlobal Warming: The Greatest Threat 2006 Deborah L. Williams
2. Animals 3. Wetlands and forests 4. Weather and storms
5. People and culture
Impacts in Alaska
Melting Sea Ice 23% smaller than
1. Melting
previous minimum; 39% smaller than average Ice 50% thinner(D. A. Rothrock et al., 1999)Global Warming: The Greatest Threat 2006 Deborah L. Williams
Ice only 3 feet thickin most locations(NOAA FAQ, 2007)
Arctic Sea Ice Extent, 1978 - 2008
In September 2007 an area thesize of Florida (69,000 square miles) melted in six days (NSIDC 2007)
Humpback whales spotted inArctic Ocean for first time in 2007
Impacts in Alaska
The Ice Cap in September New minimum:
1. Melting
1.59 million square miles (4.13 million square km)September median ice edge 1979-2000
Previous minimum:2.05 million square miles (2005)
Sea Ice edge Sep. 16, 2007
Average minimum:2.60 million square miles (1979 2000)
1 million square miles is an area roughly the size of Alaska and Texas combined, or ten United Kingdoms (NSIDC, 2007)
Melting Sea Ice: Sept. 2008Arctic sea ice extent reached annual low on September 12, 2008: The second-lowest level ever 33% less than average minimum from 1979-2000
Impacts in Alaska 1. Melting
NSIDC (2008)
Melting Sea Ice Arctic winter ice 2008: Loss of older, thicker (12 15 ft) ice
Impacts in Alaska 1. Melting
Old ice (6+ years) has declined from over 20% to about 6% Over 70% of ice is first-year
NSIDC (2008)
Impacts in Alaska
Melting Sea IceThe Arctic Ocean could be ice-free in summer by 2040.(U.S National Center for Atmospheric Research 2006)
1. Melting
Our research indicates that society can still minimize the impacts on Arctic ice.Global Warming: The Greatest Threat 2006 Deborah L. Williams
Dr. Marika Holland, National Center for Atmospheric Research
2000
2040
Impacts in Alaska
Glacial RetreatMcCall Glacier The rapid retreat of Alaskas glaciers represents 50% of the estimated mass loss by glaciers through 2004 worldwide(ACIA, 2004)
1. Melting
Loss of over 588 billion cubic yards from 1961 to 1998 (Climate Change, 11/05) Alaskas glaciers are responsible for at least 9% of the global sea level rise in the past century (ACIA, 2004) Bering Glacier, representing more than 15% of all the ice in Alaska, is melting twice as fast as previously believed, releasing approximately 8 trillion gallons of water per year into the ocean -- or the equivalent of two Colorado Rivers(Michigan Tech Research Institute, 5/07)
1941 1958USGS photo
2004 2003
Bruce Molnia photo
Matt Nolan photo
Austin Post photo
Impacts in Alaska
Glacial Retreat Accelerated melting of glaciers and ice caps could add an additional 4 to 9.5 inches of sea level rise. (Science 7/07)
1. Melting
Alaskas Columbia Glacier has decreased by approximately 9 miles since 1980 and thinned by as much as 1,300 feet.. (Science 7/07)
Impacts in Alaska
Permafrost ThawingAll the Observatories show a substantial warming during the last 20 years, causing permafrost to melt at an unprecedented rate. (State of theArctic 2006)
1. Melting
Soil Temperature at 20m Depth Soil Temperatures at-6C0 DEPTH
Osterkamp and Romanovsky Osterkamp and Romanovsky Franklin Bluffs
19872003
2003z
-8C
Average Deadhorse Deadhorse 1987-
West Dock West Dock
-10C
1m |
|
|
|
|
|
|
|
-8 -7 1980
-6
TEMPERATURE
-5 1988
-4
-3 -2 1996
-1oC
2004
NSIDC
Consequences: Damage to infrastructure, lakes, rivers, and forests Rising sea levels Release of stored carbon (methane and CO2)
Vladimir Romanovsky photo
Impacts in Alaska
Animals at Risk Polar bears Walruses Ice seals Black guillemots Kittiwakes Salmon Caribou Arctic grayling
2. Animals
Rising temperatures Shrinking habitat Food harder to get Expanding diseases Competition
Impacts in Alaska
Polar Bears in Peril Numbers in western Hudson Bay have declined 22% in 17 years (U.S. GeologicalService & Canadian Wildlife Service, 2005)
2. Animals
Global Warming: The Greatest Threat 2006 Deborah L. Williams
87% on sea ice (19791991) vs. 33% on sea ice (1992-2004) (Monnett et al., 12/05) Alaska polar bear drownings in 2004: 4 documented, 27 estimated total(U.S. Minerals Management Service, 2004)
Cannibalism in 2004(Amstrup et al., 2006)
Photo environmentaldefense.org. All rights reserved
Impacts in Alaska
Polar Bear CannibalismPhotos courtesy of Steven Amstrup, USGS
2. Animals
Amstrup et al., Polar Biology - accepted March 27, 2006 Springer-Verlag 2006
Impacts in Alaska
Polar Bears in Peril Cubs perishing (61 cubs per 100 females between 196789; 25 cubs per 100 females between 1990-2006 ), smaller skulls and adult starvation(Regehr & Amstrup, 2006)Global Warming: The Greatest Threat 2006 Deborah L. Williams
2. Animals
Shifting denning sites: 62% on ice (1985-94); 37% on ice (1998-2004) (Fischbach et al., 2007) USGS predicts the extirpation of Alaskas polar bears by 2050, with an overall elimination of two-thirds of the global population (USGS, 2007) Secretary Kempthorne proposed listing the polar bear as threatened
Impacts in Alaska
Walrus Warning Signs
2. Animals
Female walruses depend on sea ice over the continental shelf for feeding and nursing platforms Abandoned walrus calves: They were swimming around us crying (Aquatic Mammals 4/06) Haulout on Land: Thousands of walruses on shore in Alaska in 2007; 40,000 in one haulout in Russia (AP 10/07) Stampeding Deaths: 3,000 to 4,000 stampeding deaths in Russia in 2007 Other Concerns: More energy expended in foraging; depleted habitat; increased calf mortality
Global Warming: The Greatest Threat 2006 Deborah L. Willia