1. Artic climate and Climate Change Oleg Anisimov, State Hydrological Institute, St.Petersburg, Russia oleg@oa7661.spb.edu oleg@oa7661.spb.edu

2. There were two periods in the beginning and at the end of the 20 th century when the global air temperature rose continuously. Recent warming begun in 1970 th, continues now, and is most likely attributable to the cumulative effect of natural variability and anthropogenic factors. Temperature increase over the 20 th century has been 0.6 0 C, which is the largest of any century during the past 1,000 years. Climate models predict amplified warming in the Arctic, and impacts on natural and human systems are expected Is global climate changing?

3. Air temperature changes from 1951-1975 to the periods 1976-1985 (A) and 1986-1997 (B). AB Is regional climate changing? Alaska Siberia

4. http:/zubov.atmos.uiuc.edu/ACIA/ 2000 2010 2030 2050 2070 2090 0 5 4 3 2 1 GCM-based scenarios of climate change for the Arctic Annual-mean air temperature, 60 0 - 90 0 North.

5. GCMs predict very different patterns of the future climate

6. Empirical scenario of climate change based on regression analysis of historical weather records

9. Cryospheric indicators of climate change: permafrost permafrost ground ice ground ice snow snow sea ice sea ice river and lake ice river and lake ice glaciers glaciers ice caps ice caps Permafrost legend continuous discontinuous sporadic offshore permafrost ice sheet ice extent in September ice extent in April

10. How are glaciers changing?

11. How is snow cover extent changing? Anomalies of spring air temperature over snow covered areas in the Northern Hemisphere, 1972-2000 Anomalies of snow cover extent over Northern Hemisphere, 1966-2000

12. How is sea ice extent changing?

13. Arctic hydrology River runoff to the Eastern Arctic Seas increased by 10%-12% since 1970 th, while in the Western Arctic there was no significant change.

14. Annual and winter temperature rise (deg. C) in the Arctic Ocean basin during last two decades of XXth century

15. Annual runoff changes (%) in the basins of Russian rivers during last two decades of XXth century

16. Winter runoff changes (%) in the basins of Russian rivers during last two decades of XXth century

17. Circumpolar Active Layer Monitоring programme

18. Flow chart of equilibrium permafrost model of intermediate complexity Air temperature Precip Vegetation Soil Snow Snow model Calculation of surface temperature Surface temperatureTemperature amplitude Calculation of seasonal thawing Map of seasonal thaw depth

19. Projected changes of near-surface permafrost distribution under climatic scenarios for 2030, 2050, and 2080 *. * Scenarios were derived from the following GCMs 1 – Canadian Climate Center Model (CCC), 2 – NCAR model, 3 - European Max-Plank Institute model (ECHAM), 4 - GFDL climate model, 5 - UK Hadley Center model (HadCM3). http:/zubov.atmos.uiuc.edu/ACIA/

20. SFI – based distribution of near-surface permafrost. 2 – reduction of sporadic zone by 2030 3 – reduction of sporadic zone by 2050 4 – reduction of sporadic zone by 2080 5 – stable discontinuous zone 6 – reduction of sporadic zone by 2030 7 – reduction of sporadic zone by 2050 8 – reduction of sporadic zone by 2080 9 – stable continuous zone HadCM3 CCCNCAR ECHAMGFDL

21. Sce- nario Total permafrost area, mln. Km 2 and % from modern Continuous permafrost area, mln. Km 2 and % from modern 203020502080203020502080 CCC 23.7221.9420.669.838.196.93 87%81%76%79%66%56% ECHAM 22.3019.3117.649.377.255.88 82%71%65%75%58%47% GFDL 24.1122.3820.8510.198.857.28 89%82%77%82%71%59% HadCM3 24.4523.0721.3610.479.447.71 90%85%78%84%76%62% NCAR 24.2423.6421.9910.6910.069.14 89%87%81%86%81%74% Predicted changes of the near-surface permafrost extent

22. Projected changes of seasonal thaw depth under climatic scenarios for the 11-year time slices centered on 2030, 2050, and 2080 *. * Scenarios were derived from the following GCMs 1 – Canadian Climate Center Model (CCC), 2 – NCAR model, 3 - European Max-Plank Institute model (ECHAM), 4 - GFDL climate model, 5 - UK Hadley Center model (HadCM3). http:/zubov.atmos.uiuc.edu/ACIA/

23. HadCM3 CCCNCAR ECHAMGFDL Projected for 2030 changes of seasonal thaw depth (relative to 2000) 0 – ocean 1 – permafrost-free land 2 – 0% - 20% increase 3 – 20% - 30% increase 4 – 30%-50% increase 5 – >50% increase

24. Projected for 2050 changes of seasonal thaw depth (relative to 2000) 0 – ocean 1 – permafrost-free land 2 – 0% - 20% increase 3 – 20% - 30% increase 4 – 30%-50% increase 5 – >50% increase HadCM3 CCCNCAR ECHAMGFDL

25. Projected for 2080 changes of seasonal thaw depth (relative to 2000) 0 – ocean 1 – permafrost-free land 2 – 0% - 20% increase 3 – 20% - 30% increase 4 – 30%-50% increase 5 – >50% increase HadCM3 CCCNCAR ECHAMGFDL

26. Feedbacks in climate- permafrost-vegetation system

27. Circumpolar Arctic tundra Arctic polar desert Shrub tundra Southern tundra Northern Arctic tundra Polar desert ShrublandTussock tundra Northern tundra

28. Plant-cover induced pattern in the active layer of dwarf shrub-tussock tundra: a)Sphagnum mosses preserve permafrost from thawing b)under tussocks, dwarf shrubs and especially bare ground the active layer gradually increases (adopted from Razzhivin 1999). Climate-induced changes of vegetation may either enhance, or mitigate the direct impact of warming on permafrost. None of the currently existing permafrost or vegetation models accounts for such effects.

29. Total non-vascular plant biomass warm Fert. + warm Ferti- lization Biomass of Deciduous shrubs warm Fert. + warm Ferti- lization Biomass of Evergreen shrubs warm Fert. + warm Ferti- lization Biomass of lichens warm Fert. + warm Ferti- lization Biomass of mosses warm Fert. + warm Ferti- lization Total vascular plant biomass Ferti- lization Fert. + warm Empirical evidence of vegetation response to changing climate, Toolik Lake, Alaska, and Abisco Research station, Sweden (Preliminary data from the paper by M.T. van Wijk et all., in review for publiction) Treatments: 1.Fertilization 10 g m 2 y -1 N; 2.6 g m 2 y -1 P; 9 g m 2 y -1 K; 0.8 g m 2 y -1 Mg 2.Warming 2 – 4 0 C 3.Shading 50% - 65% Biomass changes in logarithmic scale in the range –0.8 +0.8, response bars correspond to individual biomes.

30. Active-layer thickness and permafrost temperature calculated under the conditions of projected for 2030 climate (HadCM2 scenario) and various vegetation conditions. 1.Bare ground. 2.5 cm thick organic layer 3.10 cm thick organic layer 4.15 cm thick organic layer 5.20 cm thick organic layer. Organic layer 5cm Total decrease of AL volume -2265 km 3 ALT reduction relative to bare ground, % 2% < dALT < 10% 10% < dALT < 20% 20% < dALT < 50% dALT > 50% Mean ALT reduction -12% 0 25 50 75 100 ALT reduction, cm 2см < dALT < 10см 10см < dALT < 30см 30см < dALT < 50см dALT > 50см Mean ALT reduction -15cm 0 25 50 75 100 Permafrost cooling compared to bare ground 0.1 С < dT < 0.5 С 0.5 С < dT < 1.0 С 1.0 С < dT < 1.5 С 1.5 С < dT < 2.0 С dT > 2.0 С

31. ALT reduction relative to bare ground, %Permafrost cooling compared to bare ground ALT reduction, cm Organic layer 10cm Mean ALT reduction -27% Total decrease of AL volume -4399 km 3 Mean ALT reduction -28сm 0 25 50 75 100 2% < dALT < 10% 10% < dALT < 20% 20% < dALT < 50% dALT > 50% 2см < dALT < 10см 10см < dALT < 30см 30см < dALT < 50см dALT > 50см 0.1 С < dT < 0.5 С 0.5 С < dT < 1.0 С 1.0 С < dT < 1.5 С 1.5 С < dT < 2.0 С dT > 2.0 С

32. ALT reduction relative to bare ground, %Permafrost cooling compared to bare ground ALT reduction, cm Organic layer 15cm Mean ALT reduction -43% Total decrease of AL volume -6408 km 3 Mean ALT reduction -41cm 0 25 50 75 100 2% < dALT < 10% 10% < dALT < 20% 20% < dALT < 50% dALT > 50% 2см < dALT < 10см 10см < dALT < 30см 30см < dALT < 50см dALT > 50см 0.1 С < dT < 0.5 С 0.5 С < dT < 1.0 С 1.0 С < dT < 1.5 С 1.5 С < dT < 2.0 С dT > 2.0 С

33. ALT reduction relative to bare ground, %Permafrost cooling compared to bare ground ALT reduction, cm Organic layer 20cm Mean ALT reduction -60% Total decrease of AL volume -8301 km 3 Mean ALT reduction –54cm 0 25 50 75 100 2% < dALT < 10% 10% < dALT < 20% 20% < dALT < 50% dALT > 50% 2см < dALT < 10см 10см < dALT < 30см 30см < dALT < 50см dALT > 50см 0.1 С < dT < 0.5 С 0.5 С < dT < 1.0 С 1.0 С < dT < 1.5 С 1.5 С < dT < 2.0 С dT > 2.0 С

34. Concluding remarks 1.To get insight into the current and future climatic and environmental changes in the Arctic we need to combine and analyze data coming from different observational networks and obtained using different technlogies (i.e. ground vs remote observations), which is why coordination with other national and international scientific initiatives focused on high latitudes is needed. Several such initiatives (NEESPI, Boreas, etc.) are on the way. 2.Models are (almost?) the only tool currently used to predict future environmental situation in the Artic. Important task is to minimize the gap between the scales at which environmental data in the Arctic are available and models operate and to validate the models using observational data making them thus capable of predicting the future changes of the environment in the Arctic. 3.One of the important deliverables of the CEON may be an effective data assimilation system that includes both observations and modeling. Example of such system in climatology is reanalysis of the temperature and precipitation fields, and our challenging task is to develop similar system for the environmental parameters in the Arctic. 4.To be easily disseminated and used effectively by the scientific community, deliverables of the project such as data bases, models and data assimilation techniques, should be usable as stand-alone products. 5.This will require developing a dedicated computerized information system in association with the project. The role of such system is three-fold: - depository of the project deliverables; - research and educational tool; - stand-alone product for easy dissemination.