Climate Data Analysis of Existing Weather Stations in around the Central Alaska Network (CAKN) Including Denali National Park and Preserve, Wrangell-St. Elias National Park and Preserve, and Yukon-Charley Rivers National Preserve. Prepared for: National Park Service Central Alaska Inventory and Monitoring Network Prepared by: Richard A. Keen, Ph.D. 34296 Gap Road Golden, CO 80403 April 2008 Table of Contents Abstract of project .............................................................................................................................................. 1 1. Purpose of the study ....................................................................................................................................... 2 2. Types of data and Documentation of the stations. ......................................................................................... 3 A. Climate (COOP) stations...........................................................................................................................3 B. Snow monitoring stations. .........................................................................................................................3 C. Remote Automated Weather Stations (RAWS).........................................................................................3 3. Sources of data ............................................................................................................................................... 4 A. National Climate Data Center (NCDC).....................................................................................................4 B. Environment Canada..................................................................................................................................4 C. Western Regional Climate Center (WRCC)..............................................................................................5 D. NASA Goddard Institute for Space Studies (GISS)..................................................................................5 E. Alaska Climate Research Center (ACRC) .................................................................................................5 F. Snow Surveys.............................................................................................................................................5 G. Climate Diagnostics Center (CDC) ...........................................................................................................5 H. Remote Automated Weather Stations (RAWS) ........................................................................................6 4. Alaska climate monitoring stations – list and maps ....................................................................................... 7 A. Appendix 1, Alaska Station Data Inventory..............................................................................................7 5. Data Summaries – Normals, means, extremes ............................................................................................. 11 A. Appendix 2, “Coop Station Normals” .....................................................................................................11 B. Appendix 3, “Alaska Snow Course SWE Averages 1971-2000 .............................................................11 C. Appendix 4, CAKN area stations with published CLIM20 Summaries..................................................11 6. Long time series of data ............................................................................................................................... 12 A. Temperature.............................................................................................................................................12 B Snow and Snow Water Equivalent ...........................................................................................................29 C. Precipitation.............................................................................................................................................32 7. Analysis of Climate change over the past century ....................................................................................... 34 A. Indicators of climate change....................................................................................................................34 B. Correlations between CAKN climate and Climate Indices .....................................................................37 C. CAKN temperatures and the North Pacific mode and Pacific Decadal Oscillation................................43 D. Century scale variations of the PDO .......................................................................................................54 E. CAKN Summer temperatures ..................................................................................................................55 F. Trends in Annual temperatures ................................................................................................................57 G. CAKN precipitation (SWE) and other indices ........................................................................................58 H. CAKN precipitation (SWE) and Arctic Sea Ice extent ...........................................................................60 8. Microclimatology of the Rock Creek Basin................................................................................................. 62 9. Summary and Recommendations................................................................................................................. 67 A. Temperature.............................................................................................................................................67 B. Snow and Snow Water Equivalent. .........................................................................................................70 C. Precipitation (rainfall)..............................................................................................................................70 D. RAWS stations. .......................................................................................................................................70 E. Rock Creek Basin Microclimatology Stations.........................................................................................70 10. References .................................................................................................................................................. 71 Appendix 1. Alaska Station Data Inventory..................................................................................................... 72 Appendix 2. CAKN region NWS Coop stations for which 1971-2000 normals have been published...........78 Appendix 3. Alaska Snow Course SWE Averages: 1971-2000 (inches), from NWCC. .................................85 Appendix 4. CAKN area stations with published CLIM20 Summaries ......................................................... 86 ii List of Figures Figure 1. Location of NWS Coop stations in central Alaska (from NOAA/NCDC) Figure 2. Stations in Alaska for which the WRCC has data files and summaries (from WRCC) Figure 3. All stations (NWS Coop, Snow Survey, and RAWS) Figure 4. NWS Cooperative Stations Figure 5. Snow Survey sites Figure 6. RAWS Stations Figure 7. Snow Survey sites in interior Alaska. Figure 8. Snow Survey sites in south central Alaska. Figure 9. Cooperative stations with 82 or more years of record. Figure 10. Location of 12 long-term climatological stations. Figure 11. First year of continuous record for 12 stations Figure 12. 1971-2000 climatological normal annual temperatures for 9 stations. Figure 13. 105 year record of Eagle annual temperatures. Figure 14. 105 year record of Eagle summer temperatures. Figure 15. 80 years of summer maximum temperatures at McKinley. Figure 16. 80 years of summer maximum temperatures at Eagle and Cordova. Figure 17. Winter minimum temperatures at Eagle, McKinley, and Cordova. Figure 18. Yearly occurrence of zero degree temperatures at Eagle, McKinley, and Cordova. Figure 19. CAKN Temperature departures, Coldest year 1956 Figure 20. CAKN Temperature departures, 2nd coldest year 1972 Figure 21. CAKN Temperature departures, Cold year 1996 Figure 22. CAKN Temperature departures, Coldest winter 1965 Figure 23. CAKN Temperature departures, Cold winter 1999 Figure 24. CAKN Temperature departures, Coldest summer1965 Figure 25. CAKN Temperature departures, Warmest year 1926 Figure 26. CAKN Temperature departures, Warm year 2002 Figure 27. CAKN Temperature departures, Warmest summer 2004 Figure 28. CAKN Temperature departures, Warmest winter 1977 Figure 29. CAKN Temperature departures, Warm winter 2003 Figure 30. 105 year record of regional Annual Average Temperature Figure 31. 105 year record of regional Summer Average Temperature Figure 32. 105 year record of regional Winter Average Temperature iii Figure 33. 105 year record of regional Annual Average Temperature, degrees C Figure 34. 105 year record of regional Annual Average Temperature, degrees C, from Jones et al. Figure 35. 105 year record of regional Annual Average Temperature, degrees C, from GHCN Figure 36. Denali summit temperatures, from NCAR/NCEP re-analysis. Figure 37. Denali area Snow Water Equivalent (SWE), from records at 19 snow survey sites. Figure 38. Wrangell-St. Elias area Snow Water Equivalent (SWE), from records at 18 snow survey sites. Figure 39. Yukon-Charley area Snow Water Equivalent (SWE), from records at 9 snow survey sites. Figure 40. CAKN regional Snow Water Equivalent (SWE),