Climate Change and Conservation – Part II

1. Climate Change and Conservation – Part II

2. Arctic Ocean Ice Cover

3. Arctic Ocean Ice Cover

4. Loss of Arctic Ocean Ice

5. Polar Bear (Usinus maritimus)

6. Polar Bear as Indicators • In 2007, the US Fish and Wildlife Service listed the polar bear as a threatened species • The polar bear is a significant seal predator and depends on ice as a platform to hunt seals • There are three distinct subpopulations that will be differentially affected by changing sea ice • Projected reductions in arctic sea ice will result in the loss of 2/3 of the population by 2050

7. Global Change and Antarctic Food Webs • Changing sea temperatures can have numerous impacts on food webs • Ice cover and melting influences light and nutrient levels and phytoplankton growth • Phytoplankton blooms fuel zooplankton like krill that feed cetaceans, pinnipeds, fishes, etc. • Krill have been influenced by local climate changes

8. Western Antarctic Peninsula

9. Global Change in Polar Regions

10. Global Change and Krill

11. Global Change in Polar Regions

13. Climate Change and the California Current • Changes in winds and water temperature will affect the food web of the California Current System • Upwelling is a critical driver for the pelagic marine food web • Upwelled water brings nutrients and fuels higher trophic levels • Climate change can influence winds and currents associated with upwelling

14. Coastal Upwelling

15. Ekman Transport

16. Climate Change and the Calfornia Current • Several studies (Sydeman et al. 2006 and Lee et al. 2007) have documented changes in populations of sea birds • Cassin’s auklet is a planktivorous bird that is a good indicator of changes • Long-term data link declines in upwelling and warming sea surface temperatures with declining popuaation

17. Cassin’s Auklet

18. Cassin’s Auklets

19. California Current and Cassin’s Auklets

20. Cassin’s Auklets

21. Climate Influences

22. Other Seabirds

23. Other Seabirds

24. Other Seabirds

25. Climate Change in Tropics

26. Impacts on Coral Reefs

27. Impacts on Coral Reefs

28. Impacts on Coral Reefs Hoegh-Guldberg 1999

29. Impacts on Coral Reefs

30. Long-Term Trends

31. Ocean Acidification • Increasing CO2 can lead to changes in the oceans concentration of calcium carbonate • Increased CO2 will increase the amount dissolved in ocean water • This will increase carbonic acid and lower the ocean’s pH • This will reduce the amount of aragonite in the water possibly to below saturation • This will make it more difficult for corals and other organisms that use calcium carbonate

32. Ocean Acidification

33. Changes in Calcification

34. Changes in Calcification

36. Millenial Cycles Bond et al. 2001

37. Decadal Cycles Fligge and Solanki 2001

38. Decadal Cycles Larsen 2005

39. Decadal Cycles Larsen 2005

40. Methane Hydrates • Heating of the deep ocean may have released large amounts of methane from methane clathrates • Methane hydrates or clathrates are ice compounds filled with methane gas that remains solid at low temperature • Typically in moderate depths 300-2000 m and temps near 2oC • At higher temperature they can release lots of methane, which is a much more efficient green house gas

41. Methane Hydrates Figure 1. Stability field (temperature and pressure) of methane hydrates (Dickens et al., 1995). Note the effect of warming by about 4oC from an initial deep water temperature around 11oC, leading to dissociation of hydrates over an ocean-wide zone of several hundreds of m thick.

42. Methane Hydrates • End of the Paleocene about 60 million years ago, the earth’s ocean suddenly warmed (Late Paleocene Thermal Maximum) • Associated with ocean warming of 4-6 degrees C • Complete extinction of unicellular eukaryotes like foraminifera • The oceans went anoxic

43. Late Paleocene Thermal Maximum

44. Methane and Thermal Increase

45. Ocean Temperatures

46. Methane Hydrates Figure 2. Sizes of organic carbon reservoirs (Kvenvolden, 1998).

47. Burning Ice