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US GLOBEC Pan-Regional Synthesis: An Outsider's View

US GLOBEC Pan-Regional Synthesis: An Outsider's View. Ken Denman Canadian Centre for Climate Modelling and Analysis Meteorological Service of Canada University of Victoria & Institute of Ocean Sciences-DFO, Sidney, BC Email: ken.denman@ec.gc.ca. U. Victoria. Outline of Talk.

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US GLOBEC Pan-Regional Synthesis: An Outsider's View

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  1. US GLOBEC Pan-Regional Synthesis:An Outsider's View Ken Denman Canadian Centre for Climate Modelling and AnalysisMeteorological Service of CanadaUniversity of Victoria& Institute of Ocean Sciences-DFO, Sidney, BC Email:ken.denman@ec.gc.ca U. Victoria US-GLOBEC Boulder Nov 06

  2. Outline of Talk GLOBEC Motivation and Hypotheses • what about the 'GLOB' part? long term and large scale Where is US GLOBEC Today? • mature regional studies and capabilities Key Questions and Approaches • 'local insights' versus 'universal truths'? The State of Marine Ecosystem Modelling • reuniting foodweb versus biogeochemical models A Look into the Future • climate change and other human impacts • thinking beyond funding US-GLOBEC Boulder Nov 06

  3. Motivation for GLOBEC (Kawasaki et al.) BUT what is natural and what is caused by (over)fishing? There exist hemispheric, multidecadal changes US-GLOBEC Boulder Nov 06

  4. (S. Lluch-Cota, 2005) A Closer Look • Lack of synchronicity in anchovy cycles • Negative correlation with Benguela systemin S. Atlantic Ocean Plots like these for your study regions would be a highly desirable but unattainable outcome of the US GLOBEC program US-GLOBEC Boulder Nov 06

  5. Working Hypothesis #1 We want to understand the systems we are studying well enough to 'forecast' their future behavior • Events such as the 'physteria hysteria' off the Carolinas, or Hurricane Katrina, capture all the news. Our society tends to react immediately and intensely to these events. But how can we respond (rather than react) as a scientific community so as to help minimize the likelihood/risk of occurrence and/or severity of such events in the future? • These 'crises' & our personal, institutional and funding horizons lead us to focus on shorter term, smaller scale, 'process-level' studies US-GLOBEC Boulder Nov 06

  6. Working Hypothesis #2 When GLOBEC ends, it should be seen as having put our Society in a better position to address issues of Global Change Definition: Global change = Environmental change resulting from human activities and from climate change both natural and anthropogenic. US-GLOBEC Boulder Nov 06

  7. Yet Much Environmental Change of Consequence Occurs on ENSO to Century Timescales • Statistical predictions will likely fail as the system moves beyond the ensemble of realizations on which the statistics were based. • Forecasting these timescales results in the system 'losing its memory' of initial conditions • We must assume future forcing conditions • Parameters must be formulated to adapt as the ocean environment changes US-GLOBEC Boulder Nov 06

  8. Yet Much Environmental Change of Consequence Occurs on ENSO to Century Timescales • Statistical predictions will likely fail as the system moves beyond the ensemble of realizations on which the statistics were based. • Forecasting these timescales results in the system 'losing its memory' of initial conditions • We must assume future forcing conditions • Parameters must be formulated to adapt as the ocean environment changes US-GLOBEC Boulder Nov 06

  9. Where is US GLOBEC Today? • You have completed intensive field programs on Georges Bank, in the Pacific Northwest/Alaska, & in the Southern Ocean: • they combine submesoscale projects with 'monitoring' on seasonal to interannual scales • you have developed advanced sampling technology & detailed mechanistic spatially-resolved coupled physical-biological models to capture and integrate the understanding gained from the field programs. • You are about to enter into your 'Synthesis' phase and need a set of criteria to focus calls for proposals and eventually the reviewing of the proposals. • You want to leave a LEGACY US-GLOBEC Boulder Nov 06

  10. Key Questions and Approaches 1. Which scientific advances made by US GLOBEC have been 'local insights' and which ones are 'universal truths'? Can we learn from studies 'Contrasting' the different regions studied? • physically-controlled vs top-down predator controlled? • dominated by event-scale phenomena, versus seasonal and longer scales? • systems that 'erase the past' and reset each year (or after each 'event', e.g. El Niño, 'regime shift', etc.), versus those that integrate over multiple years and have 'memory'? US-GLOBEC Boulder Nov 06

  11. Key Questions and Approaches 2. How much of the detail built into the regional models is 'Portable'? Portability IndexPI: whereJ(Ri)is the cost function of fitting to region RiJ(Rj // Ri)is the cost of fitting toRjafter optimizing onRi AS– Arabian Sea &EP– Equatorial Pacific [Friedrichs, M. A. M, J. Dusenberry, L. Anderson, R. Armstrong, F. Chai, J. Christian, S. Doney, J. Dunne, M. Fujii, R. Hood, D. McGillicuddy, K. Moore, M. Schartau, Y. Spitz, and J. Wiggert, 2006. Assessment of skill and portability in regional marine biogeochemical models: the role of multiple plankton groups. J. Geophys. Res., submitted July 2006] US-GLOBEC Boulder Nov 06

  12. No Optimization Local Optimization Simultaneous Optimization Cross-validation Model Intercomparisons and 'Portability' • Models with multiple Phytoplankton classes (rhs) perform better than 1P models when applied to different regions (bottom panels) • Simple models perform almost as well as complex models in 'local optimization' (panel b) [Friedrichs et al, submitted] US-GLOBEC Boulder Nov 06

  13. No Optimization Local Optimization Cross-validation Simultaneous Optimization Model Intercomparisons and 'Portability' • EqPac:Chlorophyllconstraint accounts for largest cost • Arabian Sea (not shown):Productivityconstraint more important • Complex Models-different models with similar cost may have very different internal flows- need more observations of 'internal' variables to constrain flows US-GLOBEC Boulder Nov 06

  14. Portability Index Lower Cost  Higher Portability OOPS!Assimilating zooplankton data  Higher Cost & Lower Portability WHY?? US-GLOBEC Boulder Nov 06

  15. 3. Which functional representations in our models are or can be formulated so that they vary with a changing climate? (Do our approaches allow for 'emergent'? properties?) Consider the Chlorophyll: Carbon ratio for example: • our models are expressed in terms of Cor N yet we estimate phytoplankton biomass from Chlorophyll, and Chlorophyll captures PAR, the light used in photosynthesis • we obtain variable based on the equation for 'balanced' Chl:C of Geider et al. 1996, 1997, and • observations/analyses from OSP during SUPER (Booth et al, 1993) & our own during 1998-2000 (Peña & Varela, in prep.)  tedious • our 'balanced'  is based on the previous 24h PAR (Jim Christian) US-GLOBEC Boulder Nov 06

  16. C:Chl (= 1/ ) from OSP and Shelf Edge First cruise?? - Winter: low, no gradient; Summer: 40 - 100 [Peña & Varela, submitted] US-GLOBEC Boulder Nov 06

  17. C:Chl Ratio for Variable PAR at OSP • Smooth black line is • Red line is 'balanced' 1/for PARt-1 averaged over the upper 30 m • Range ~ 25 – 120 gC/gChl • BUT Chl changes little at OSP? • smooth black line is average daily PAR at OSP • mid-summer clear sky PAR ~ 150+ W m-2 US-GLOBEC Boulder Nov 06

  18. Current State of Marine Ecosystem Modeling Over the last decade, marine ecosystem model development has diverged into several lines of more or less independent activity. These include: • upper food web models incorporating individual-based models (IBMs) and life history models of herbivores and harvestable marine resources; • trophic models spanning many trophic levels but focusing on harvestable marine resources; • biogeochemical models coupled to physical climate models. US-GLOBEC Boulder Nov 06

  19. End-to-End Ecosystem Modeling 'E2E' International GLOBEC/ IMBER has organized an End-to-End Ecosystem Task Team (e2e), whose goal is: • to guide the development of a full ecosystem approach that links all components of the food web with comprehensive climate models to explore the impacts and feedbacks between global change (in its broadest sense) and marine food webs. (North American members: Dave Karl & Ken Denman). US-GLOBEC Boulder Nov 06

  20. US GLOBEC Synthesis could have a goal to develop an ecosystem model that would work equally well (according to some 'cost function') in all your regional study areas, embedded in the same (ROMS?) circulation model. • Need better metrics of uncertainty • Need ensemble projections: • give relative probability of different outcomes • evaluate risk of the different outcomes • Coupling the large scales to the small scales, i.e. downscaling US-GLOBEC Boulder Nov 06

  21. A Look into the FutureGlobal warming is here to stay • Annual rates of emissions of CO2 are increasing, and will continue to do so for the foreseeable future (at least 30 years, due to coal generation plants) [see next 2 slides] • Polluting aerosols will be tackled and reduced due their short atmospheric lifetimes and to the more immediate threat to human health – which will lead to an increase in the rate of warming (due to current cooling effect of aerosols) • All C4MIP coupled carbon-climate models show a positive feedback to climate, i.e. coupled models all sequester less CO2 to land and oceans than uncoupled (Friedlingstein et al., 2006, J. Climate.) US-GLOBEC Boulder Nov 06

  22. 2 x CO2 Stabilizing Concentrations Requires Large Decrease in Emissions from Y 2000 Level Stabilizing Concentrations at 550 ppm requires Decreasing CO2Emissions by ~75% from present levels IPCC TAR, 2001 US-GLOBEC Boulder Nov 06

  23. What Next? Rise in Coal-Fired Plants vs. Carbon Capture and Storage Capability Schiermeier, Q., News feature, Nature 442, 10 Aug. 2006. IEA estimates they will release 140 GtCcf. 165 GtCanthro. left in atmosphere in 1995 About 50% will remain in atmosphere (based on last 50 years) i.e. equivalent to an increase in atmospheric CO2 of 33 ppm US-GLOBEC Boulder Nov 06

  24. What Kind of Future? • Stabilizing CO2 levels at 550 ppm by 2100 ('2 x CO2') is probably not attainable through controlling emissions. • Stabilizing CO2 around 700-750 ppm is more likely OR ? ? • We need to consider mitigation measures,e.g. proposal to inject sulphates into the stratosphere, [Paul Crutzen, 2006, Climatic Change] US-GLOBEC Boulder Nov 06

  25. ? The Ocean: Surface pH is DecreasingHow will that affect fisheries ecosystems? [prepared by Arne Körtzinger (IFM,Kiel) for the IMBER Science Plan on the basis of WOCE data: Schlitzer, 2000] http://ioc.unesco.org/iocweb/co2panel/Publications.htm US-GLOBEC Boulder Nov 06

  26. The Coastal Ocean: More Hypoxia Events? Dead zone off Newport, Oregon 2002,04,06 [www.piscoweb.org PISCO at OSU] US-GLOBEC Boulder Nov 06

  27. Hypoxia Events: Are They Increasing? What are the causes? • natural? • climate change? • other human activities? Can we predict them? [Grantham et al., 2004. Nature, 429, 749-753] US-GLOBEC Boulder Nov 06

  28. Our Future? • Our community doing 'basic' science will be expected to spend more effort addressing impacts (& risk analysis) + adaptation + mitigation measures. • That requires improved projections of our future climate and ocean, and inclusion of more 'impacts' directly into our models US-GLOBEC Boulder Nov 06

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