1. Mark Brush CHRP-EPA Jul 2015 Workshop

2. Motivation As part of a NOAA Coastal Hypoxia Research Program project: Apply a novel, reduced complexity, parsimonious ecological model to predict hypoxia in Narragansett Bay Implement within a fast running, coarse boxed scheme linked to a fine resolution hydrodynamic model allowing for annual updates (JV) and with an Officer box model allowing >10 years of runs (MB) Simulate responses to nutrient reductions and climate change Make the model available for direct use by managers.

3. COMPARISON OF THE MODELS EcoGEMEcoOBM Nearly Identical, Simplified Ecology  Officer approach to exchanges using river flow and salinity (fast running, online)  Exchanges capture effects of tides, winds, & river flow through ROMS  Daily temporal resolution (captures events)  2006-07 (so far)  Adding additional years or flow scenarios requires additional ROMS runs  ROMS dye-tracking approach to exchanges (most defensible hydrodynamics possible)  Daily temporal resolution although driven by 10-day moving-average flows  No explicit winds or tides (although exchanges implicitly include these effects through forced salinity)  2001-09 (additional years in progress)  Adding additional years only requires new data, but flow scenarios still require a linkage between flow and changes in salinity  Concept: EcoGEM includes the most rigorous simulation of hydrodynamics so should be used as the primary management tool; EcoOBM provides a semi-independent, longer-term confirmation.

4. Narragansett Bay EcoOBM: Ecology * * *

5. Phytoplankton NPP: Carbon Flux to Sediments: Denitrification: Empirical Formulation of Key Rate Processes: Plankton Community Respiration: Narragansett Bay EcoOBM: Ecology

6. EcoOBM: Sensitivity

7. Officer Box Model: exchanges = f (freshwater, salinity) Fast run times Exchanges independent of ROMS; constrained by salinity Enables long term runs: e.g., 2001-09 (through 2013/14 coming)

8. Freshwater Inputs 7 gauged rivers: Blackstone Moshassuk Woonasquatucket Ten Mile Pawtuxet Taunton Hunt Gauged flow extrapolated to the entire watershed; Hunt R. used in other ungauged areas WWTFs: Fields Point Bucklin Point East Providence Fall River PPT (TF Green – NOAA) Evaporation (computed)

9. InsomniacsNuShuttle + Buoys + Box Model: Exchanges = f (freshwater, salinity) We now have a continuous daily record of T and S in each model element, plus T, S, DO, and Chl in RIS.

10. Nutrient InputsRIS Boundary T, S, O 2, Chl-a, DIN, DIP Watershed: Mean river concentrations (DIN, DIP, TOC) computed from Nixon et al. (1995); multiplied by daily flows WWTFs: DIN, DIP (estimated) & BOD from plants multiplied by flows Atmosphere (dry + wet): DIN, DON: Fraher (1991); Nowicki & Oviatt (1990) DIP, DOP: Nowicki & Oviatt (1990) Meteorology (precip, wind, Ta, Td) – TF Green (NOAA) PAR – Eppley Lab  NOAA Kingston Other Forcing Data NuShuttle

11. EcoOBM: Exchanges Compared to ROMS Rogers (2008) vs. 3D ROMS 2D box model Destination Box Fraction of Water Box Model ROMS Source Box 2006 ROMS output from D. Ullman; Comparison by J. Vaudrey

12. EcoOBM: Calibration Data Stocks: Chl-a: Smith & Oviatt 2006-09 Buoys 2001-09 GSO dock 2001-09 [NBC] DIN/DIP: NuShuttle 2006-09 GSO dock 2001-09 [NBC] O 2 : Insomniacs 2001-09 Buoys 2001-09 NuShuttle 2001-09 Rates: Prim Prod: Smith & Oviatt 2006-09 Resp (water): Smith & Oviatt 2006-09 Resp (sed): Fulweiler 2005-06 DNF: Fulweiler 2005-06 Oviatt buoy P & R  open water [not yet included]

13. EcoOBM: Surface Layer Chl-a Green: Smith & Oviatt Grey: buoys Box 13: MERL GSO dock mg m -3

14. EcoOBM: Surface DIN Red: NuShuttle/CHRP Box 13: MERL GSO dock MM

15. EcoOBM: Phyto NPP Green: Smith & Oviatt g C m -2 d -1

16. EcoOBM: Water Column Resp Green: Smith & Oviatt g C m -2 d -1

17. EcoOBM: Sediment Resp Points: Fulweiler g C m -2 d -1

18. EcoOBM: Surface DO Points: Insomniacs Red: NuShuttle Grey: buoys mg l -1

19. EcoOBM: Bottom DO Points: Insomniacs Red: NuShuttle Grey: buoys mg l -1

20. EcoOBM: Bottom DO 2006 - 09 Points: Insomniacs Red: NuShuttle Grey: buoys mg l -1

21. EcoOBM: Annual Hypoxia Index 2006 2007 2009

22. Model predicts daily mean DO But state criteria are for: instantaneous minimum DO time with DO below 2.9 mg/l time with DO below 1.4 mg/l Empirical Linkages to Assess State Criteria: Temporal Variability 15 minute buoy data

23. Model predicts daily mean DO within each box Empirical Linkages to Assess State Criteria: Spatial Variability Insomniacs YSI profiles

24. Publications & Products Publications: Brush et al. 2002 – MEPS (BZI formulation) Brush & Brawley 2009 – J Mar Sys (BZI depth correction) Brush & Harris 2010 – Ecol Model special issue (guest editors & introduction) Brush & Nixon 2010 – Ecol Model (macroalgae model with DO effects) Kremer et al. 2010 – Ecol Model (EcoGEM approach) Lake & Brush 2011 – Est Coast Shelf Sci (benthic microalgae in Narragansett Bay) Harris & Brush 2012 – Ecol Model (BZI temperature correction) Lake & Brush 2015 – Estuaries & Coasts (EcoOBM in the York River, VA) Brush & Harris in press – Encyclopedia of Estuaries (modeling entry) Ganju et al. in press – Estuaries & Coasts (model review paper) Lake & Brush in review – MEPS (EcoOBM in the York River, VA – climate) Brush & Nixon in review – Springer hypoxia book (EcoOBM in Greenwich Bay, RI) Products: Online EcoOBM Brush, M.J. 2014. Narragansett Bay EcoOBM v1a. Online CHRP models. www.vims.edu/research/departments/bio/programs/semp/models/index.php

25. Online EcoOBM www.vims.edu/research/departments/ bio/programs/semp/models/index.php

26. Online EcoOBM

31. Output also available for chl-a, DIN, and DIP

32. CHRP II Scenario Runs

33. Nutrient Load Scenarios

35. Effect of Timing

36. Climate Scenarios

38. Interactive Effects of Nutrients and Warming

39. Empirically-Varying Salinities Insomniacs data, 2001-09: Flow into Box 1

40. Empirically-Varying Salinities x = 10-day moving average FW input to Box 1, m 3 d -1 y = mean layer salinity from Insomniacs cruises, 2001-09

41. Wider Applicability of the Model

42. Cross-System Comparisons