fluxnet at lathuile, 2007: synthesizing co 2 and water vapor fluxes from across a global network

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FLUXNET at LaThuile, 2007: Synthesizing CO 2 and Water Vapor Fluxes From Across a Global Network Dennis Baldocchi ESPM/Ecosystem Science Div. University of California, Berkeley LaThuile, Italy, Feb 2007

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FLUXNET at LaThuile, 2007: Synthesizing CO 2 and Water Vapor Fluxes From Across a Global Network. Dennis Baldocchi ESPM/Ecosystem Science Div. University of California, Berkeley. LaThuile, Italy, Feb 2007. Acknowledgements. Data Preparation - PowerPoint PPT Presentation

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  • FLUXNET at LaThuile, 2007: Synthesizing CO2 and Water Vapor Fluxes From Across a Global NetworkDennis BaldocchiESPM/Ecosystem Science Div.University of California, BerkeleyLaThuile, Italy, Feb 2007

  • AcknowledgementsData PreparationDario Papale, Markus Reichstein, Catharine Van Ingen, Deb Agarwal, Tom Boden, Bob Cook, Susan Holladay, Bruce Wilson, +++Networks AmeriFlux, CarboEurope, AsiaFlux, ChinaFlux, Fluxnet Canada, OzFlux, +++AgenciesNSF, ILEAPS, DOE/TCP, NASA, Microsoft, ++++

  • FLUXNET: From Sea to Shining Sea400+ Sites, circa 2007

  • Global distribution of Flux Towers with Respect to Climate

  • Institutional Memory:Evolution of FLUXNETMeasure Annual Cycle of NEEMicromet issues of Detrending, Transfer Functions, Flux Sampling and Measurements, Gap-filling, Error AssessmentMeasure and Interpret Intra-annual Variation of NEEFlux partitioning (GPP & Reco); assessment of metadata,e.g. Vcmax, soil respiration, LAI, biomass inventories. Quantifying Biophysical Controls on FluxesMeasure and Interpret Inter-annual variations of NEEMeasure NEE over multiple Land-Use Classescrops, grasslands, deciduous and evergreen broadleaf and conifer forestsDisturbance, logging, biodiversity and fireManipulative StudiesNitrogen and H2O additionsMeasure NEE over Representative AreasScaling Flux Information of Footprint to MODIS pixelWorkshopsLaThuile Italy, 1995Flathead Lake MT, 1997Marconi CA, 2000Orvieto Italy, 2002Lake Tahoe CA, 2003Firenze Italy, 2004

  • FLUXNET Successes

    Mountains of data from a spectrum of canopy roughness and stability conditions, functional types and climate spaces have been collectedA Model for Data SharingFLUXNET Web Site, a venue for distributing Primary, Value-added and Meta-Data productsValue-Added Products have been producedDevelopment of Gap-Filling TechniquesProduction of Gap-Filled Daily and Annual SumsMany New Findings on Emergent Processes, Environmental Controls and Seasonality and Annual C fluxesData for Validating and Improving SVAT models used for weather, climate, biogeochemistry and ecosystem dynamicsCollaboration & Synthesis through Workshops and Hosting VisitorsBuilding a Collaborative, Cooperative, Multi-Disciplinary & International Community of ResearchersTraining New and Next Generation of Scientists, Postdocs, Students

  • Finding and Correcting Data Problems:e.g. Degradation of Licor Quantum SensorCourtesy of Alessandro Cescatti

  • Failures/Un-resolved IssuesNot Measuring Night-time Fluxes WellNot Measuring Fluxes over Complex terrain and during Advection WellImPerfect U* correction New Gu AlgorithmImPerfect Flux PartitioningWorks Better on Longer Time ScalesImPerfect Energy Balance ClosureCould be red-herring based limited Rn and G fetchNeed Better Outreach and TrainingBeing Rectified at LaThuile with Participation of New Generation of Fluxnet Scientists

  • FLUXNET 2007++New Issues/Questions RaisedProduction of New, Expanded DataBaseUse of New Software Tools to Facilitate DataBase Navigation & ExplorationBroader representation of vegetation types and climates on NEE, GPP and Reco. Roles of natural and human induced disturbance on C FluxesImpacts of climate and ecosystem factors on inter-annual variations of carbon, water and energy fluxes. Use FLUXNET data to provide ground-truth information to validate and anchor NPP and fpar products being produced by MODIS LAND Perform geostatistical analyses with the FLUXNET database to examine the scales of spatial coherence of net carbon, water and energy fluxes across landscapes, regions and continents and to quantify the network connectivity among groups of sites. Revisit many basic tenets of bio- & micrometeorologyData are being collected from a spectrum of land surface types (short grasses and crops, through open heterogeneous canopies to tall, closed forests) on flat to moderately undulating terrain over a wide range of atmospheric stability conditions Intermittent Turbulence

  • Current and Future Scientific DirectionsNEE in Urban and Suburban, Africa, India, Latin America and High Arctic EnvironmentsQuantifying and Understanding the controls on Interannual Variability of C and energy FluxesMonitoring the Metabolism of Ecosystems as we undergo Global ChangeCoupling CO2, Trace Gas Deposition/Emission (O3, voc) and Methane FluxesAdopting New Technology (TDL, wireless networks) to embellish flux measurementsCouple tower data with Real-time Data Assimilation Models.Boundary Layer Budgets using Fluxes and High Precision CO2 measurementsSpectral reflectance measurements and Digital Photos across the network for phenology and dynamics of structure and functionSpatial-Temporal Network-Scale AnalysisReal-time Data AssimilationMatching Footprints of Tower and PixelsModel Lags, Switches and PulsesUsing Fluxnet data to assess problems inEcology, Ecohydrology, Biogeochemistry, Biogeography, Remote Sensing, Global Modeling, BiodiversityTesting Maximum Entropy, Ecosystem Ecology, Biogeography and EcoHydrology Theories

  • Recent Results and Advances:Lessons Learned, Those to be Refined & Lets not Re-Invent the WheelProcessesCanopy-Scale Response Functions Emergent ProcessesFlux Partitioning, NEP=GPP-RecoAcclimationCarbon-Water CouplingTimeDaily/Seasonal DynamicsPulses, Lags, SwitchesIntra- + Interannual VariabilityStand Age/Disturbance SpaceClimate/Structure/FunctionCoherence/GradientsUpscaling with Remote Sensing

  • Probability Statistics of NEECan we Integrate C Fluxes Probabilistically, driven with Spatially-Gridded Climate Data?

  • Light and Photosynthesis:Emergent Processes at Leaf and Canopy Scales

  • CO2 Flux and Diffuse RadiationNiyogi et al., GRL 2004We need more sites measuring RdiffBe poised to see effects of Cleaner Skies and Next Volcano

  • Sims et al 2005 AgForMetDo Snap-Shot C Fluxes, inferred from Remote Sensing, Relate to Daily C Flux Integrals?

  • Heinsch et al. 2006 RSEMODIS GPP Algorithm Test

  • Optimal NEE: Acclimation with TemperatureE. Falge et al 2002 AgForMet; Baldocchi et al 2001 BAMS

  • Linking Water and Carbon:Potential to assess Gc with Remote SensingXu + DDB, 2003 AgForMet

  • Gc Scale Invariance?Task to Expand with New DatabaseProcessed by M. Falk

  • Budyko Evaporation Index

  • Temporal Dynamics of C FluxesHourDayMonthSeasonYearMultiple YearsPulsesLagsSwitches

  • Data of Katul and DettoMultiple Turbulence TimeScales

  • Complicating Dynamical FactorsSwitches/PulsesRainPhenology/Length of SeasonFrost/FreezingEmergent ProcessesClouds & LUEAcclimationLags Stand Age/Disturbance

  • Decadal Plus Time Series of NEE:Flux version of the Keelings Mauna Loa GraphData of Wofsy, Munger, Goulden et al.

  • Knohl et al Max Planck, JenaLag Effects Due to Drought/Heat Stress

  • Photosynthesis-Respiration:Do These Relations Hold with a Larger Database?Marconi Data Set, Falge et al AgForMet 2002

  • DNEE scales with DRe vs DGPPBaldocchi, unpublished; FLUXNET Published database

  • Data of Pilegaard et al.Soil Temperature: An Objective Indicator of Phenology??

  • Baldocchi et al. Int J. Biomet, 2005Soil Temperature: An Objective Measure of Phenology, part 2

  • Baldocchi, unpublishedSpatialize Phenology with Transformation Using Climate Map

  • White, Baldocchi and Schwartz, unpublishedFlux Based Phenology Patterns with Match well with data from Phenology Network

  • NEE and Length of Growing Season:Does the Function Remain with More Data from More Sites?

  • Spatial Variations in C Fluxes

  • Validating MODIS Vegetative Index AlgorithmsFalk, Ma, Baldocchi, unpublished

  • Spatialize Flux data: Look for Coherence and Network Connections

  • Limits to Landscape Classification by Functional TypeStand Age/DisturbanceBiodiversityFireLoggingInsects/PathogensManagement/PlantationsKyoto Forests

  • Effects of Stand Age:After LoggingLaw et al. 2003 Global Change Biology

  • Testbed for Ecohydrological TheoryMiller et al, Adv. Water Research, on-line

  • Biodiversity and EvaporationBaldocchi, 2004: Data from Black, Schmid, Wofsy, Baldocchi, Fuentes

  • Mean Soil Temperature Scales with Mean Air Temperature

  • Test Climatology:Accurate Humidity information is Achilles Heel of MODIS Flux scaling

  • Work that drives atmospheric circulation is derived from the Equator to Pole Temperature gradient

    Transport of heat from Equator to Pole downgrades that energy and produces Entropy

    Maximum Entropy Production suggests that turbulent motion of the atmosphere and oceans adjusts with respect to the heat transport coefficient, k

    Maximum Entropy Production, Climate and Life

  • Courtesy of Gaby Katul

  • ForestEcosystem

    TimeScale

    Flux Spectrum

    day

    season

    Scale

    Spectrum for MaximumTheoretical Entropy

    EnergyRedistribution

    Rn Input

    FluxOutput

    High Entropy(Disordered)

    Low Entropy(Organized)

  • At Poles, ice and snow reflect sunlightAt Equator, high incident solar energy evaporates water forms clouds and reduces available energyMaximum Entropy Production occurs near the TropicsKleidon and Lorenz, 2005Maximum Entropy Production, s, and Radiation Budget

  • Region with abundant sunlight has low soil moisture and low stomatal conductance and low photosynthesisRegions with open stomata have ample water and produce clouds, reducing available sunlight and photosynthesisMaximum Entropy Production, s, Photosynthesis and Stomatal ConductanceCourtesy of Axel Kleidon

    Coherent response among sites, impact of length of growing season. Does not account for interannual variability at a site, due to snow cover, drought, cloudy vs clear summers etc.