Craig E. Tweedie PhD Department of Biology and the Environmental Science and

1. Climate Change Impacts on Polar Terrestrial Ecosystems: Their Importance to the Future State of the Earth System Craig E. Tweedie PhD Department of Biology and the Environmental Science and Engineering Program, UTEP ctweedie@utep.edu www.armap.org www.ipyroam.org www.baidims.org www.ceoninfo.org www.ceonims.org

3. Current Research Directions • Assessing the impact and feedback of climate change on arctic terrestrial ecosystems and other extreme environments. • Improving interdisciplinary environmental observing networks at local to international scales. • Building innovative technologies and cyberinfrastructure to improve capacities for environmental observation and analysis. • Improving future research capacities by providing life changing educational opportunities to students and teachers.

4. Temperature Trends

5. Atmospheric Change Observed Air temperature trend 1949-06. Global Change Models predict that differential warming of the Arctic will continue throughout the next century. CGCM2 Modeled Air temperature trend 1990- 2100. Change in temperature greatest at northern high latitudes (IPCC). Arctic is connected to the global system & cannot be studied in isolation.

6. http://www.acia.uaf.edu/

7. System Science Approach • Hardest thing to teach, learn and understand ~ excellent approach for inquiry based learning • Aims to understand how change in one part of the system regulates and/or invokes change in another component of the system • Understanding connectivity is key to understanding the complexity of the system • Concept originated in electrical engineering ~ switches, voltage regulators, circuit boards etc

8. Discussion Topics for Today • Carbon balance and cycling in arctic terrestrial ecosystems – why the big deal? • Feedbacks in polar terrestrial ecosystems • Carbon cycling ~ warming, species shifts • Albedo ~ ice retreat, species shifts • Impacts of change on polar biodiversity ….. Learning activity using a system science approach to predict changes in arctic terrestrial ecosystems

9. Carbon Balance is important in the Arctic!!! • Arctic terrestrial ecosystems are important to global carbon balance. • Why is this? • What are the major pools of carbon in arctic terrestrial ecosystems? • Why is carbon arranged in these pools? • How does this compare to human greenhouse gas emissions?

10. www.baidims.org

13. Distribution of the major terrestrial biomes Campbell Biology 4th Edition

14. Global relevance of tundra land area, plant carbon, Net Primary Production, and soil carbon Tundra Land Area = 9 % Plant Carbon = 1 % Deserts Grasslands Boreal Forest Temperate Forest Net Primary Production = 2 % Soil Carbon = 28 % Tropical Forest Lakes and Wetlands Croplands Ice (Adapted from WB GU, 1998)

15. Global relevance of tundra land area, Plant carbon, Net Primary Production, and soil carbon Controls: • Coastal erosion, river and stream erosion, treeline, human development. • Species composition, historical factors, many other physical and non-biological factors e.g. herbivores, climate etc. • Plant carbon, Net Primary Production, cold temperatures, water logged soils, permafrost, soil acidity, microbial and fungal activity. Land Area = 9 % Plant Carbon = 1 % Net Primary Production = 2 % Soil Carbon = 28 %

16. Arctic Carbon Rich Soils Seasonal Active Layer Carbon Store C.E. Tweedie

17. Arctic Carbon Rich Soils Seasonal Active Layer • Current atmosphere: 750 GT C • Vulnerable arctic soils: • 350-900 GT C • Human C emissions: • 5.4 GT C per year • 1% loss arctic soil C = annual human C emissions. • Could equate to a global warming capacity of 4-8°C. Carbon Store C.E. Tweedie

18. Feedbacks in Arctic Terrestrial Ecosystems • Understanding positive and negative feedbacks in the Arctic system is important for developing models that could predict the future state of the Arctic and global system • Understanding connections and feedbacks are key to pinpointing vulnerabilities, processes driving non-liner change, and how adaptation and mitigation can be most effective e.g…. • Carbon cycling ~ potential changes to Arctic Carbon pools • Albedo ~ longer snow free period, species change, glacial retreat

19. Atmospheric GHGs C Soil Microbial Respiration Aerobic CO2 PERMAFROST Anerobic CH4 Greenhouse warming CO2 CH4= 23 x CO2 CO2 Albedo Photosynthesis

20. Observed Snow Cover Change Barrow, Alaska

21. Observed Snow Cover Change Barrow, Alaska Carbon CO2 Carbon Dioxide CH4 Methane Albedo

22. Lake Disappearance in Russia Smith et al. (2005) Science 308:1429

23. Lake Disappearance in Russia Carbon CO2 Carbon Dioxide CH4 Methane Albedo Smith et al. (2005) Science 308:1429

24. Greening trend (NDVI) 1982-91 Spring temp. trend 1982-90 (Myneni et al. 1997)

25. Summary of Observed Tree and Shrub Expansion Arctic Report Card 2007

26. Shrub expansion Alaska 1949 – 2001 (Sturm et al. 2001)

27. Shrub expansion Alaska 1949 – 2001 Carbon CO2 Carbon Dioxide CH4 Methane Albedo (Sturm et al. 2001)

28. It is estimated that shrub and tree expansion may magnify regional warming by a factor of 2-7 IPCC (Intergovernmental Panel on Climate Change) 2007.

29. Species are Important! • Albedo ~ shrubs and trees absorb more energy than tundra • Differences in photosynthesis • Different Net Primary Production that leads to the deposition of carbon in the soil • Differences in ability to transport methane from the soil to the atmosphere • Differences in the way they impact soil thermal properties and permafrost • …Affect other ecosystem variables as well

30. Biological Change 5 Key ways species respond to environmental change: • Acclimation – individual physiological response that can be linked to genetics • Adaptation – species respond genetically through natural selection • Reorganization – some species compete for resources better than others • Migration – behavioral response of animals only • No change – species could become vulnerable to extinction • All of these can co-occur… simple isn’t it!!!

32. Cool – mean annual air Temp ~ 0.5°C Warm – mean annual air Temp ~ 4.5°C

35. Flowering delayed with low temperature ~ plants at low altitude finish flowering before plants at high altitude start and therefore do not share genetic material… natural selection acting differently at low altitudes compared to high altitudes.

36. Plot Based Land Cover Change at Barrow: 1972 2000 • Dry heath: • Little change in species cover and abundance. • Little change in species richness.

37. Plot Based Land Cover Change at Barrow: 1972 2000 • Pond communities: • Dramatic change in species cover and abundance. • Increase in species richness. • Evidence of pond ‘closure’.

38. Barrow IBP Topographic Grid: 110m 390m • Significant change in vegetation cover has occurred across the IBP site suggesting overall drying trend. • Model suggests a decline of 208 g/ha/16th August in Carbon fixing potential due to land cover change alone ~900 g for the entire grid 10% 1972 total.

39. New challenges present themselves when we scale biological change across ecosystem types and across trophic levels…..Wait till you get to your learning activity and realize the challenge first hand

40. Conclusion • System science ~ understanding connectivity in the system is important • Carbon balance in the arctic is important ~ pools, cycling, balance • Feedbacks both positive and negative • Carbon ~ • Albedo ~ snow, vegetation change • Species response to change is important • There are many challenges that lay ahead.

42. Lots of fun… till it catches fire and you have to jump out going full speed across the tundra!!!!…

43. The telly-tubbies conquest of the Russian Far East!!!

44. The Hilton Hotel Laboratory

45. Hungry?

46. Lavrentia in Eastern Russia…

50. Was that you? ….the water got warm all of a sudden….