The Changing Arctic:

1. The Changing Arctic: Recent Events & Global ImplicationsMartin O. JeffriesNational Science Foundation Office of Polar Programs Division of Arctic Sciences Presentation to the Seasons and Biomes Workshop Fairbanks, AK, 27 September 2007

2. CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 Radiative effect 20:1 Radiative effect 1:300 CH4 NO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 Increasing Greenhouse Gas Concentrations in the Atmosphere Source: BBC

3. Greenhouse Gases and Increasing Global Temperature Source: BBC Computer models can not simulate the 20th Century global air temperature trend unless increased atmospheric greenhouse gas concentrations are included.

4. Computer Simulation of Global Temperatures Non-uniform geographic distribution of temperature increase. Arctic amplification of global warming. Why arctic amplification? Regional positive feedback processes. Source: BBC IPCC: Inter-governmental Panel on Climate Change

5. Albedo () The ratio of reflected solar radiation to total incoming solar radiation. A black object has an albedo of 0 (zero). That is, all solar radiation is absorbed. A white object has an albedo of 1 (one). That is, all solar radiation is reflected.

6. 16 September 2007 Record minimum, 4.1 x 106 km2 16 August 2007 21 September 2005 Source: National Snow and Ice Data Center (NSIDC) 5.3 x 106 km2 5.3 x 106 km2 August ice extent, 1979-2007 Arctic Sea Ice Retreat: A Positive Feedback Extent (106 km2) 2007

7. Sea Ice Loss: The Real World Outpaces the Virtual World

8. 279 species of migratory bird breed in significant numbers in the Arctic. Of those, 30 reach southern Africa, 26 reach Australia and New Zealand, 22 reach southern South America, and several species reach the Southern Ocean. Arctic Change has the potential to affect biodiversity far from the Arctic. Arctic tern Consequences of a Declining Sea Ice Cover On 7 September 2007, the US Geological Survey reported the results of a study that predicts that by 2050 the polar bear population will be reduced by 66%. The reduction will not be evenly distributed - polar bear populations in some regions will not survive the loss of sea ice - they will disappear completely. Changing polar bear populations are a very visible and emotional sign of ecosystem change.

9. Northern Sea Route Source: BBC 2 August 2007 Source: NSIDC Northwest Passage Natural Resources, International Trade and Geopolitics Source: BBC S.S.Manhattan, NW Passage, 1969

10. People & Communities Shishmaref, Alaska

11. Source: Vladimir Romanovsky Arctic Coast Central Alaska Rising Ground Temperatures

12. Thawing Permafrost Thermokarst Landscape Change & Methane (CH4)

13. Methane gas

14. Bacteria make methane(decomposition)

15. Arctic methane & permafrost

16. Methane Mobilized: Another Positive Feedback Source: MOJ

17. Increased Melting on the Greenland Ice Sheet