1. Oceanic Remote Chemical/optical Analyzer (ORCA) An autonomous profiler monitoring water quality in south Puget Sound T,S, O2 NO3, ORCA overall; Steven Emerson; Allan Devol Jan Newton; Rick Reynolds PRISM John Dunne; Wendi Ruef General Support Nutrient Analyzer

2. Develop a robust remote chemical and biological monitoring system T, S, Light, Meteorology NO 3, O 2, Chl-a, turbidity NH 4, Gas Exchange parameters Telemeter data back to UW Monitor the spectrum of time-scales Hourly (tides), Daily (solar), Weekly (plankton growth), Monthly (blooms), Annual (seasons, and inter-annual, e.g., El Nino) Describe natural variability and characterize and help evaluate potential human influence Validate PRISM physical and biological models ORCA GOALS

3. WHAT DOES ORCA LOOK LIKE? light solar panel radar reflector superstructure Platform and housing For Winch, electronics, etc Atlas float (cut away view) ballast ring anchoring (break in scale) package weather station ORCA Schematic View 4.2 m solar panel

5. WHERE IS ORCA?

7. Seattle Tacoma

8. http://www.ocean.washington.edu/research/orca/

9. Nutrient Analysis

10. Spring Bloom Movie Fall Bloom Movie Growing Season Movie

11. Basic data shows varibility

12. July 12 - 28, 2000 enhancement October 15-21, 2000Sept. 20- Oct. 2, 2000 no enhancementsurface enhancement Sigma-t Chl ug/l O2 mg/l Effect of nutrient addition on phytoplankton productivity blue = ambient production red = spiked with NH 4 and PO 4 Carr Inlet, WA Ecology

13. What Causes varibility ?

14. Tidal Advection ? What causes high frequency variability ?

15. Wind and destratification ?

16. Analysis by Kate Edwards

18. Photosynthesis (J) CO 2 + H 2 O + nutrients CH 2 O + O 2 O 2 flux C flux 5 m Mixed   Deep mixing 1. How frequently do we need to sample? 2. What is gross O 2 production (GP)? 3. What is net community O 2 production (NCP)?

19. How frequently do you need to sample? Gas Exchange = G* (O 2sat -O 2obs ) Gas exchange (moles m -2 d -1 ) 2-hr0.012 Daily0.0210.0200.0210.0190.0210.0220.0210.020 Weekly0.0280.0140.0180.0290.0240.0210.0230.010 Bi- Weekly 0.0130.0140.0180.0360.0080.3270.0160.009 Monthly0.0070.0190.0210.0480.0120.0190.0180.009 G=f(average daily wind speed) (Liss and Merlivat, 1986)

20. Diurnal O 2 Change Model 200 250 300 350 400 450 500 8509009501000 jDay O2 mmoles/m3/d 1Apr. 10 Oct. So, how do we get O 2 production terms?

21. diurnal O 2 change 1) night-time respiration, R = 14 mmoles m -3 (d/2) -1 2) Assume R~ constant, thus, R =28 mmoles m -3 d -1 *5 m = 140 mmoles m -2 d -1 3) Since dO2/dt = 0 over 24 h, R = j = 140 mmoles m -2 d -1 (j = O 2 production required to balance R) Amplitude ~ 14 mmoles m -3

22. Hourly Oxygen Averages

23. Box Model for net oxygen production h * dO 2 /dt h * dO 2 /dt = G *  O 2 + K z * dO 2 /dz + NCP h * dO 2 /dt h * dO 2 /dt = observed box depth & oxygen change with time G *  O 2 = gas exchange: wind speed; oxygen gradient across air-water interface K z * dO 2 /dz = vertical diffusion: diffusion coefficient & observed vertical oxygen gradient NCP = net biological oxygen production: determined from model G = f (average daily wind speed) (Liss and Merlivat, 1986) K z = f (buoyancy frequency) (Denman and Gargett, 1983)

24. Simple Box Model Results NCP = 0.011 moles m -2 d -1 (132 mg C m -2 d -1 ) G.E. = -0.012 moles m -2 d -1 Vertical mixing = -0.0008 h (dO 2 /dt) = -0.0021 Is This Reasonable ?

25. regression = 380-320 mmoles m -3 (380-320)/150 = 0.4 mmoles m -3 d -1 h*(dO 2 /dt) = 2.1 mmoles m -2 d -1 (2.1mmoles m -2 d -1 )/(5m)=0.4mmoles m -3 d -1 1Apr. 10 Oct. NCP=0.011, G.E.=-0.012, mix=-0.0008, h*dO 2 /dt=-0.0021 Conclusion: NCP ~0.011 mmoles m -2 d -1

26. GP = j + G.E. = 140 + 12 = 152 mmoles m -2 d -1 (1824 mg C m -2 d -1 ) What, then is GP?

27. Figure 15. Seasonal levels of ambient primary production integrated over the euphotic zone. Data shown are Apr. 99, Jul. 00, Sep. 99 and Dec. 99. Newton and Reynolds, 2000

28. Y = 1.22 X 0.85 r 2 = 0.93 Chl Based Productivity Model * * Rick Reynolds

29. Productivity Model Input Data Daily- Integrated Surface Insolation Daily depth- Integrated Chl

30. Modeled * Daily Production at The Carr Inlet-ORCA Site * Rick Reynolds model

31. Production Summary mmoles m -2 d -1 mg C m -2 d -1 Mixed layer net O 2 production 10120 Mixed layer Gross O 2 production 1501900 14 C-based Model production 3400

32. High frequency sampling reveals high frequency features Some of the high frequency signal is due to tidal effects Frequent sampling required to capture the true value of certain fluxes, e.g. gas exchange Bloom starts when water air temperature becomes equal to water temperature Frequent summer destratification driven by wind events Production can be derived from oxygen distribution Wrap Up

35. Orca Home Page

37. Longer Term Goals Science Study Bloom Dynamics/gas exchange/nutirent/physics coupling Mixed layer Aphotic zone Add Sensors (PO4, Eddy Correlation, micro- gradient) Publish Orca Results Expand Network: South Sound, Main Basin, Hood Canal, Admiralty Inlet Continue and Expand Outreach/Education

38. Advection

39. Production

40. Goals for 2003 Science Goals: MIXED experiment (April 2003) Nutrients; NO3 and NH4 Move Orca for Brightwater Publish Orca Results Prism Goals: Use Orca to Validate ABC-POM Carr Inlet Brighwater site Outreach Maintain Orca Website Orca School

41. [O 2 ] Box Model