1. Preliminary wave energy hindcast results for the circum-arctic region Preliminary wave energy hindcast results for the circum-arctic region David E. Atkinson International Arctic Research Center / Atmospheric Sciences Department University of Alaska Fairbanks David E. Atkinson International Arctic Research Center / Atmospheric Sciences Department University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

2. To begin with: > Understand the impact of waves > Understand the importance of storms - to drive waves - to drive surges Examine storm climatology results > Understand the impact of waves > Understand the importance of storms - to drive waves - to drive surges Examine storm climatology results AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

3. Atlantic track is prominent at circum-polar scale David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

4. ACD zones, weather station locations Results from Arctic Coastal Dynamics project David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

5. 3 5 7 1 2 4 6 Storm counts David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks

6. Trends in storm counts David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks - no strong trend

7. Other influences on coastal erosion In frozen regions must consider  Sea ice  Permafrost In frozen regions must consider  Sea ice  Permafrost AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

8. Trends in open water season length, 1950 - 2000 (model initialized with observations) Trends in open water season length, 1950 - 2000 (model initialized with observations) David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks Melt season increasing Reduced sea ice cover AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

9. Results from western Kara Sea coast (S. Ogorodov, Moscow State University) - influence of wave energy and temperature in permafrost coastal zones Results from western Kara Sea coast (S. Ogorodov, Moscow State University) - influence of wave energy and temperature in permafrost coastal zones AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

10. Wave energy climatologies - impetus > Wave energy principle forcing agent > Much of the circum-polar (AK) coastal zone susceptible to erosion > Problem is not easy – various parameters that must be considered - shallow zones - sea ice * ice on/off dates controls wave access * position of ice offshore controls fetch (presence of floating ice also modifies wave energy) > Coastal process models require wave energy input (I.e., and not wind) > Engineering issues > Wave energy principle forcing agent > Much of the circum-polar (AK) coastal zone susceptible to erosion > Problem is not easy – various parameters that must be considered - shallow zones - sea ice * ice on/off dates controls wave access * position of ice offshore controls fetch (presence of floating ice also modifies wave energy) > Coastal process models require wave energy input (I.e., and not wind) > Engineering issues David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

11. Desire: develop a system that will translate winds into wave energy  Driving winds – gridded is desirable - North American Regional Reanalysis for AK (32 km) - AOGCM for work with prediction scenarios > Generate climatological wave fields - monthly totals - annual totals - period means and trends (1979-2003) Provide to coastal dymanics researchers, but can also assess contribution of ice Desire: develop a system that will translate winds into wave energy  Driving winds – gridded is desirable - North American Regional Reanalysis for AK (32 km) - AOGCM for work with prediction scenarios > Generate climatological wave fields - monthly totals - annual totals - period means and trends (1979-2003) Provide to coastal dymanics researchers, but can also assess contribution of ice Scope and Approach David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

12. Wave energy calculation - 1 st order linear (Airy) approximation > Coastal Engineering Manual and Technical Reference for the Automated Coastal Engineering System (USArmy Corps of Engineers) > suitable for most applications > Represents a starting point only Wave energy calculation - 1 st order linear (Airy) approximation > Coastal Engineering Manual and Technical Reference for the Automated Coastal Engineering System (USArmy Corps of Engineers) > suitable for most applications > Represents a starting point only Scope and Approach David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

13. Wind forcing: - NCEP/NCAR reanalysis, 925 mb to overcome speed problems - direction limited to 180° (I.e. water side) Direct forcing approach, not distribution based Wind forcing: - NCEP/NCAR reanalysis, 925 mb to overcome speed problems - direction limited to 180° (I.e. water side) Direct forcing approach, not distribution based Scope and Approach David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

14. NCEP/NCAR Reanalysis wind speed problem AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005 0.7

15. NCEP/NCAR Reanalysis wind speed problem AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005 0.7

16. Scope and Approach Depth - simply specified at 10m - represents generic shelf zone Sea ice - NSIDC extent plots used - based on ice plots: > coastal region divided into 12 sectors by longitude > sectors assigned a binary ice/no ice class - turned energy on/off for that month Depth - simply specified at 10m - represents generic shelf zone Sea ice - NSIDC extent plots used - based on ice plots: > coastal region divided into 12 sectors by longitude > sectors assigned a binary ice/no ice class - turned energy on/off for that month David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

17. NSIDC Sea Ice extent from passive microwave

18. ACD zones, weather station locations Results from Arctic Coastal Dynamics project David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks 1 2 3 5 6 7 8 9 10 11 12 4 AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

19. No depth variation Winds do not catch all events (spatial resolution) Ice sector approximation Ice content (binary approach) coarse Spatial resoution coarse Orientation of wind energy wrt coastline crude (hemisphere approach) No depth variation Winds do not catch all events (spatial resolution) Ice sector approximation Ice content (binary approach) coarse Spatial resoution coarse Orientation of wind energy wrt coastline crude (hemisphere approach) Limitations David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

20. David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks 1979 total ICENo ICE

21. David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks 1998 total ICENo ICE

22. David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks 1979 – 2003 mean ICENo ICE

23. David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks 1979 – 2003 trends ICENo ICE

24. > Increase wind forcing resolution > Introduce local coastal orientation > Variable depth > Introduce variable ice concentrations, drop sector approach > Comparisons with existing observed/modeled information (e.g. Ogorodov for Pechora Sea) > Increase wind forcing resolution > Introduce local coastal orientation > Variable depth > Introduce variable ice concentrations, drop sector approach > Comparisons with existing observed/modeled information (e.g. Ogorodov for Pechora Sea) Next steps/improvements David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

25. David E. Atkinson IARC/Atm. Sci., University of Alaska Fairbanks > Trends in (circumpolar) storminess not simple linear > Ice (marine and terrestiral) must be explicitly considered for erosion work > Influence of sea ice for wave energy apparent even for this coarse approach > Wave energy trends, not just seasonal totals, influenced by sea ice conditions > Trends in (circumpolar) storminess not simple linear > Ice (marine and terrestiral) must be explicitly considered for erosion work > Influence of sea ice for wave energy apparent even for this coarse approach > Wave energy trends, not just seasonal totals, influenced by sea ice conditions Conclusions from storm and wave energy work: AK PRIDE wind/wave climatology workshop Hotel Captain Cook, Anchorage, August 2-3, 2005

26. Fin

27. Specification of wave energy  Basic energy equation:  Define H and L in terms of U and F  Returns energy for a given point  Basic energy equation:  Define H and L in terms of U and F  Returns energy for a given point