Sablefish recruitment off Sitka Island and Mesoscale Circulation

1. Sablefish recruitment off Sitka Island and Mesoscale Circulation by A. Smith, K. Shotwell (NOAA), M. Stachura (UW) and E. Di Lorenzo

2. Preface: Sablefish Early Life History Recruitment is the abundance of the youngest fish entering a population that can be estimated successfully (Myers 1998, Maunder and Watters 2003) Very noisy timeseries Sablefish Recruitment

3. Sitka Island Sablefish Recruitment

4. Mean Circulation in the Gulf of Alaska SSH Mean Satellite (Niiler et al. 2005) Sitka Island Sablefish Recruitment

5. Mean Circulation in the Gulf of Alaska SSH Mean Satellite (Niiler et al. 2005) Sitka Island Alaskan Stream Alaska Current Sablefish Recruitment

6. February 1998 SSH Anomaly Satellite (AVISO) Sitka Island 1998/02/13 Sablefish Recruitment

7. February 1998 SSH Anomaly Satellite (AVISO) Sitka Island 1998/02/13 strong downwelling events in the high sea level along the coast Sablefish Recruitment

8. February 1998 SSH Anomaly Satellite (AVISO) Sitka Island 1998/02/13 strong downwelling events in the high sea level along the coast Sablefish Recruitment stronger mesoscale Anticyclonic Eddies

9. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island 1998/03/05 strong downwelling events in the high sea level along the coast Sablefish Recruitment stronger mesoscale Anticyclonic Eddies 9

10. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island Sitka Eddy Haida Eddies 1998/03/05 strong downwelling events in the high sea level along the coast Sablefish Recruitment stronger mesoscale Anticyclonic Eddies 10

11. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island Sitka Eddy Haida Eddies 1998/03/05 Sablefish Recruitment Observation: Young sablefish have been found in large anticyclonic eddies in the Gulf of Alaska. Atwood et al. 2010 11

12. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island Sitka Eddy Haida Eddies 1998/03/05 Sablefish Recruitment Observation: Young sablefish have been found in large anticyclonic eddies in the Gulf of Alaska. Atwood et al. 2010 Hypothesis: Higher sablefish recruit years are linked to years when large anticyclonic eddies are stronger. 12

13. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island Sitka Eddy 1998/03/05 Sablefish Recruitment Observation: Young sablefish have been found in large anticyclonic eddies in the Gulf of Alaska. Atwood et al. 2010 Hypothesis: Higher sablefish recruit years are linked to years when large anticyclonic eddies are stronger (e.g. Sitka Eddy). 13

14. March 1998 SSH Anomaly Satellite (AVISO) Sitka Island Sitka Eddy 1998/03/05 Sablefish Recruitment Testing the Hypothesis: Use a regional eddy-resolving ocean model hindcast (ROMS) to generate an index of Sitka Eddy strength to use as a diagnostic for predicting sablefish recruitment timeseries 14

15. SSH Anomalies ROMS Model QUESTION: How does the model capture eddy events like the winter of 1998? Sablefish Recruitment Testing the Hypothesis: Use a regional eddy-resolving ocean model hindcast (ROMS) to generate an index of Sitka Eddy strength to use as a diagnostic for predicting sablefish recruitment timeseries

16. SSH Anomalies ROMS Model Jan 1998 ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

17. Feb 1998 Strong downwelling event high sea level anomaly ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

18. Mar 1998 Development of Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

19. Apr 1998 Sitka and Haida Eddies fully developed ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

20. May 1998 Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

21. Jun 1998 Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

22. Jul 1998 Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

23. Aug 1998 Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

24. Sitka Eddy and Haida Eddies form in the WINTER WINTER 1998 Development of Sitka and Haida Eddies ROMS eddy-resolving model hindcast from 1950-2008 Di Lorenzo et al. 2005; Combes et al., 2007; 2009;

25. Sitka Eddy and Haida Eddies form in the WINTER WINTER 1998 Sitka Eddy

26. Sitka Eddy Index: average winter SSHa in formation region of Sitka Eddy WINTER 1998 Sitka Eddy

27. Sitka Eddy Index: average winter SSHa in formation region of Sitka Eddy Correlation Map Sitka Eddy Index vs. winter SSHa Sitka Eddy

28. Sitka Eddy Index: average winter SSHa in formation region of Sitka Eddy Correlation Map Sitka Eddy Index vs. winter SSHa Sitka Eddy Sitka Eddy Index

29. Sitka Eddy Index: average winter SSHa in formation region of Sitka Eddy Correlation Map Sitka Eddy Index vs. winter SSHa Sitka Eddy Sablefish Recruitment Sitka Eddy Index

30. Sitka Eddy Index: average winter SSHa in formation region of Sitka Eddy Correlation Map Sitka Eddy Index vs. winter SSHa Sitka Eddy Sablefish Recruitment Correlation Significance Test Sitka Eddy Index R=0.45

31. Sablefish recruitment off Sitka Island and Mesoscale Circulation Hypothesis: Higher sablefish recruit years are linked to years when Sitka eddies are stronger. This is an example of using an eddy-resolving model to generate a regional physical index to diagnose and (perhaps) predict recruitment data. Sablefish Recruitment Correlation Significance Test Sitka Eddy Index R=0.45