1. Climate-driven Trends in Contemporary Ocean Productivity Michael Behrenfeld Oregon State University Robert O’MalleyJorge SarmientoWayne Esaias Don SheaGene FeldmanRobert Frouin Dave SiegelAllen MilliganCompton Tucker Emmanuel BossRicardo LetelierDorota Kolber Toby WestberryJames RandersonNathan Pollack Chuck McClainChristopher FieldStephane Maritorena Paul FalkowskiSietse Los or “The World According to SeaWiFS”

2. Biospheric NPP increased 6 Pg from 1997 El Nino to 1999 La Nina, with clearest response in oceans

3. In most central ocean gyres, chlorophyll concentrations decreased between 1997 and 2003

4. Declines in mid-ocean gyres chlorophyll associated with increases in sea surface temperature

5. 7 December 2006 Vol. 444 Nature Tidbits Based on Vertically Generalized Production Model (VGPM) Initial increase = 1,930 TgC/yr Subsequent decrease = 190 TgC/yr Global trends dominated by changes in permanently stratified ocean regions (ann. ave. SST < 15 o C) global > 15 o C

6. * * Multivariate ENSO Index Low Latitude SST Anomaly

8. SST Changes ( 0 C ) +3 +2 -2 +1 -3 0 0 -30 +60 -60 +30 NPP Changes (%) b a c NPP SST

9. Tidbits Six different coupled climate models Ocean biological responses to climate warming from industrial revolution to 2050 Marginal sea-ice biome area decreases 42% (N) and 17% (S) Expansion of low production permanently stratified ocean by 4% (N) to 9.4% (S) Subpolar gyre biome expands 16% (N) and 7% (S) Stratification decreases nutrient supply and thus productivity in permanently stratified oceans Stratification, extended growing season, and sea ice retreat enhance production at high latitudes Significant shifts in community composition

10. Year 19982000 2002 20042006 Year 19982000 2002 20042006 global > 15 o C < 15 o C

11. …are there alternative explanations? Low Latitude SST Anomaly ‘98‘99‘97‘00‘01‘02‘03‘04‘05‘06 Year Nutrient-driven changes in NPP So, what do we really know?.... Satellites measure neither NPP or chlorophyll, they tell us about optics SeaWiFS has recorded changes in ocean optical properties over vast regions These changes are clearly linked to effects of climate variability on upper ocean temperature and stratification - not instrument or atmospheric artifacts Photo-oxidation of cDOM Light-driven changes in photoacclimation

12. Spectral matching algorithms are a path to a solution… Do not rely on the ‘bio-optic’ assumption – now known to be wrong Would allow changes in cDOM photo-oxidation to be detected Would allow changes in photoacclimation to be detected from Chl:C Are not optimized with heritage ‘ocean color’ wavebands Difference in chlorophyll estimates for standard wavelength-ratio and spectral matching algorithms cDOM from spectral matching algorithm Uncertainty in remote sensing products reflects inadequacy of heritage wavebands for separating different absorbing and scattering components.

13. Measurement Maturity Index Desired Trajectory 12345678 1 2 3 4 5 6 7 8 Measurement Quality Index CZCS (1978-1985) SeaWiFS (1997 - ) MODIS (2002 - ) VIIRS (2009 - ) Advanced Mission (2013 - ) Insufficient for Climate Data Record Current trajectory Climate Data Record Quality Key Few science products Extensive science products * NOTE: MODIS Aqua climate-quality ocean biology data have only been achieved because SeaWiFS data were available for comparison * measured operationally approaches limits on performance no known use for measurement potential science return SWIR NIR Visible CZCSSeaWiFSMODIS VIIRS SWIR NIRVisibleUltraviolet 5 nm resolution (335 – 865 nm) 17 aggregate bands 2 SWIR bands

14. Backup Slides Surface Chlorophyll Anomaly (Tg) Year 19982000200220042006 > 15 o C Contemporary Changes in Ocean Chlorophyll during the SeaWiFS Era El Nino – La Nina changes Chl sat vs Chl euphotic Other NPP models Chlorophyll and MEI NPP and MEI update Zonal temperature changes Surface chlorophyll updates The 2006 minimum Credit really belongs to the Ocean Color Group at NASA Goddard Space Flight Center and Ocean Biology and Biogeochemistry Program at NASA Headquarters

15. Biospheric NPP increased 6 Pg from 1997 El Ni  o to 1999 La Ni  a, with clearest response in oceans (C)(C) (D)(D)

16. Depth-integrated Year 19982000200220042006 Surface Chlorophyll Anomaly (Tg) global > 15 o C

17. Tidbits Three models: VGPM – polynomial VGPM – Eppley CbPM – Chl:C-based growth All show 2 primary trends Biggest differences is in slope of initial El Nino – La Nina period

18. Chl SST Match Mismatch Chl SST VGPM Polynomial VGPM Eppley matchup / mismatch

20. Year 19982000200220042006 MEI

21. SST changes

22. SeaWiFS time series – sequential months Chlorophyll anomalies All bins Global > 15C < 15C

23. SeaWiFS time series – sequential months Surface Chlorophyll Anomaly (Tg)

24. Quality and Maturity Definitions Measurement Maturity Index 1 = No known operational use for measurement 2 = Parameter identified as having potential for operational significance 3 = Operational significance demonstrated through simulations 4 = Pathfinder mission launched. Need for long term record widely accepted 5 = Pilot decision support tool (DST) use of space-based measurements 6 = Space ops over sustained period. Adds value to DSTs. 7 = Ready for transfer to operational use 8 = Measured operationally. Used operationally in existing DSTs. Measurement Quality Index 1 = Measurement identified as potentially providing significant science return 2 = Initial measurements produced and calibrated 3 = Geophysical, biological, or chemical properties inferred or estimated from calibrated measurements 4 = Geophysical, biological, or chemical properties inferred or estimated from calibrated measurements and validated 5 = Significant improvement in calibration, spatial resolution, spectral resolution, temporal revisit, and/or spatial coverage over initial measurements 6 = Second significant improvement in calibration resolution, temporal revisit, and/or spatial coverage over initial measurements 7 = Further significant improvement in calibration resolution, temporal revisit, and/or spatial coverage over initial measurements 8 = Measurement approaches theoretical or practical limits on performance