1 Using Satellite Data for Climate Modeling Studies: Representing Ocean Biology-induced Feedback Effect in the Tropical Pacific Rong-Hua Zhang CICS-ESSIC, University of Maryland, USA

2 Remote Sensing for Ocean-related Climate Modeling Studies July 27-Aug SST Chl from ocean color Ocean Topex/P/J sea level - Sep 1997 Ocean Vector Winds Sea surface salinity (SSS) Precipitation

3 Model imprvovement & Bias reduction …. Ocean biology- climate feedback Satellite data => Climate Modeling MJO Forcing Tropical instability waves (TIWs) Entrainment temperature (Te) Freshwater flux (FWF) Forcing Air-sea coupling ENSO modulation ENSO prediction Interannual variability Climate Models Processes

4 mixed layer Thermocline Processes involved in ENSO: Forcings & feedbacks Thermocline SST wind

5 mixed layer Thermocline Pre Freshwater Flux Ocean Biology Tropical instability waves

6 Application of Satellite Data to Climate Modeling Tropical instability waves (TIWs)-induced surface wind forcing & feedback Freshwater flux forcing & feedback Ocean biology-induced climate feedback ….

7 Methodologies SST Chl from ocean color Ocean Vector Winds => TIWs

8 Methodologies SST Chl from ocean color Ocean Vector Winds => TIWs Empirical relationships from historical data

9 Methodologies SST Chl from ocean color Ocean Vector Winds => TIWs Empirical relationships from historical data Models

10 Using Satellite Data for Climate Modeling Studies: Representing Ocean Biology-induced Feedback Effect in the Tropical Pacific Rong-Hua Zhang CICS-ESSIC, University of Maryland, USA

11 Proposed Mechanisms for ENSO Variability Stochastic forcing in the atmosphere; The influences of extra-tropical processes; The changes in mean state of the tropical climate system; The nonlinearity and associated parameter changes; The residual effects of interannual variability; Decadal variations in the structure of wind; Decadal variations in the structure of T e. Freshwater flux forcing Physical !!!

12 A Ocean Atmosphere Ocean Biology Physical system Marine ecosystem ENSO ? If ? What ? How ? Why care about ?

13 Ocean Chlorophyll: NASA’s SeaWiFS Satellite

14 Ocean color data (SeaWiFS)

15 Effects of marine biology on ENSO Penetration of solar irradiance in upper ocean Redistribution of heating in the vertical; Modification of stratification/stability Mixing, mixed layer depth, upwelling,currents SST

16 The penetration of solar irradiance follows an exponential decline with depth: The penetrative bands on the visible part of the radiation (Morel, 1988): Ocean color data (SeaWiFS) PenetrationDepth

17 Mixed layer Subsurface layers The biological heating Rate in the mixed layer absorbed solar radiation in the mixed layer pentrative solar radiation at the base the mixed layer PenetrationDepth

18

19 SST

20 SST

21 Taking into account ocean biological feedback (OBF)  Using satellite data to explore links between the climate system & marine ecosystem;  A simple parameterization for OBF;  Effects on ocean biology on ENSO;  Understanding basic processes involved;  Role as bias sources for SST simulation;  Improving ENSO simulations & prediction ; This work

22 SL from G. Mitchum SST

23 A SVD-based Empirical Model for H' p H p = +  Hp  S vd ( SST inter )

24 S vd ( SST inter ) = H ' p

25 Interannual H p experiments  Hp = => -1.0 => 3.0

26

27 mixed layer thermocline Processes involved Depth Bio-response SST Q pen HpHp Density/stability/ Mixing /Entrainment

28 Concluding remarks An empirical model for H' p ; Large effects of H' p in a climate model : Modulation of ENSO by marine biology (amplitude, periods, phase locking …) ; Interactions: physics marine biology ; A negative feedback induced by marine biology : Processes & structure of the effects identified…. Importance of H' p but significant uncertainties exist: Estimate of H p ; modeling ocean ecosystem; physics-biogeochemistry coupling ; … A clear source for biases; this bio- forcing component be taken into account for better ENSO simulation & prediction

29 processes processes Model Model Obserevations Obserevations TIWs TIWs processes processes

30 Applications of Satellite Data to Climate Modeling Tropical instability waves (TIWs)-induced surface wind forcing & feedback Zhang, R.-H. et al., 2009: Cooling effects of tropical instability wave (TIW)-induced surface wind forcing in the tropical Pacific Ocean, J. Climate, submitted. Zhang, R.-H., and A. J. Busalacchi, 2009: An empirical model for surface wind stress response to SST forcing induced by tropical Instability waves (TIWs) in the eastern equatorial Pacific. Mon. Wea. Rev., 137, 2021–2046. Zhang, R.-H., and A. J. Busalacchi, 2008: Rectified effects of tropical instability wave (TIW)-induced atmospheric feedback in the tropical Pacific. Geophys. Res. Lett., 35, L05608, doi: /2007GL Freshwater flux-induced climate feedback Zhang, R.-H. et al., 2009: Interannual biases induced by freshwater flux and coupled feedback in the tropical Pacific, Mon. Wea. Rev., in press. Zhang, R.-H., and A. J. Busalacchi, 2009: Freshwater flux (FWF)-induced oceanic feedback in a hybrid coupled model of the tropical Pacific. J. Climate, 22, No. 4, 853–879. Ocean biology-induced climate feedback …. Zhang, R.-H. et al., 2009: Role of ocean biology-induced climate feedback in the modulation of El Niño-Southern Oscillation, Geophys. Res. Lett., 36, L03608, doi: /2008GL Zhang, R.-H., et al., 2009: Using satellite ocean color data to derive an empirical model for the penetration depth of solar radiation (Hp) in the tropical Pacific ocean, J. Geophys. Res., submitted ….

31 Thank you !!!