National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Climate Monitoring in the Southwest Alaska Network Annual Report for the 2013 Hydrologic Year Natural Resource Technical Report NPS/SWAN/NRTR—2014/857 ON THE COVER Kelvin-Helmholtz clouds over the Gulf of Alaska, Kenai Fjords National Park. The Kelvin-Helmholtz instability can occur when there is a difference in velocities across the interface between two fluids. In the cover photograph, the interface is between two layers of air with different densities that are moving at different speeds. Turbulent eddies are developing along the interface and the condensation and evaporation of water vapor in these eddies are making them visible as wave-shaped clouds. A more familiar example of the Kelvin-Helmholtz instability occurs when wind blows over water forming waves. Photograph by: Chris Lauver Climate Monitoring in the Southwest Alaska Network Annual Report for the 2013 Hydrologic Year Natural Resource Technical Report NPS/SWAN/NRTR—2014/857 Chuck Lindsay National Park Service Southwest Alaska Network Inventory and Monitoring Program 240 W 5th Avenue Anchorage, Alaska 99501 March 2014 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Technical Report Series is used to disseminate results of scientific studies in the physical, biological, and social sciences for both the advancement of science and the achievement of the National Park Service mission. The series provides contributors with a forum for displaying comprehensive data that are often deleted from journals because of page limitations. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. Data in this report were collected and analyzed using methods based on established, peer-reviewed protocols and were analyzed and interpreted within the guidelines of the protocols. This report received informal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Government. This report is available in digital format from the Southwest Alaska Network Inventory and Monitoring Program website (http://science.nature.nps.gov/im/units/swan/) and the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/). To receive this report in a format optimized for screen readers, please email [email protected]. Please cite this publication as: Lindsay, C. 2014. Climate monitoring in the Southwest Alaska Network: Annual report for the 2013 hydrologic year. Natural Resource Technical Report NPS/SWAN/NRTR—2014/857. National Park Service, Fort Collins, Colorado. NPS 953/124181, March 2014 ii Contents Page Figures.................................................................................................................................................... v Tables ................................................................................................................................................... vii Appendices ............................................................................................................................................ ix Abstract ...............................................................................................................................................xiii Acknowledgments ................................................................................................................................ xv Acronyms ........................................................................................................................................... xvii Introduction ............................................................................................................................................ 1 Climate Overview ........................................................................................................................... 1 Climate vs. Weather .................................................................................................................. 2 Average, Normal, and Period of Record ................................................................................... 2 Intrinsic Climate Patterns .......................................................................................................... 2 Climate Change ......................................................................................................................... 3 Other Resources.............................................................................................................................. 3 Methods .................................................................................................................................................. 5 Stations ........................................................................................................................................... 5 Data Acquisition, Quality Control, and Data Processing ............................................................... 5 Reporting Interval ........................................................................................................................... 9 Summary Reports and Graphs ........................................................................................................ 9 Stations Used in Analyses .............................................................................................................. 9 Results .................................................................................................................................................. 11 Regional Overview ....................................................................................................................... 11 Temperature ............................................................................................................................. 11 Precipitation ............................................................................................................................. 12 Location of Summary Reports and Graphs for Individual Stations ............................................. 16 Limitations .................................................................................................................................... 16 iii Contents (continued) Page Discussion ............................................................................................................................................ 17 Historical Context ......................................................................................................................... 17 Limitations ............................................................................................................................... 17 Temperature and Precipitation at Long-Term Stations – Data Presentation Methods ................................................................................................................................... 17 Temperature and Precipitation Changes during 1952-1976 and 1977-2001 ........................... 25 Temperature and Precipitation Changes over the Period of Record ....................................... 26 Recent Temperature and Precipitation Anomalies .................................................................. 28 PDO Conditions....................................................................................................................... 30 ENSO Conditions .................................................................................................................... 31 Weather Extremes ........................................................................................................................ 32 Status of Climate Monitoring in Network Parks .......................................................................... 34 Measuring Snow and Winter-time Precipitation ..................................................................... 34 New Weather Stations – Silver Salmon Lakes and Three Forks RAWS ................................ 37 Possible Relocation of the Fourpeaked RAWS ....................................................................... 37 Reinforcing the McArthur Pass RAWS .................................................................................. 38 Summary of Issues Affecting Performance and Data Quality During 2013 ........................... 39 Common Reporting and Technical Review ............................................................................ 40 Conclusion ..........................................................................................................................................