Fluxnet 2009 Progress Dennis Baldocchi, Rodrigo Vargas, Youngryel Ryu, Markus Reichstein, Dario Papale, Deb Agarwal, Catharine Van Ingen, Bob Cook GEWEX Meeting, Melbourne Australia

FLUXNET Community Outreach NewsLetter, FluxLetter Workshops LaThuile, Feb. 2007 Asilomar, Feb 2009 Distributed, Searchable Database, www.fluxdata.org 250 + sites; 950+ site-years Coordinating Synthesis Projects and Papers Fluxnet Visitors Paul Stoy, Sebastiaan Luyssaert, Josep Penuelas, Bart Kruijt

FLUXNET DataBase, www.fluxdata.org QA/QC Data Standardization (names, units) Version Control Flux Integrals Computed Daily, Monthly, Annual U* corrections Gap-Filling Flux Partitioning Converting NEE into GPP and Reco Compiling Multi-faceted Site MetaData Data Searchable/Distributed/Manipulatable/Archived Curating, wikis, community feedback

Emerging Ideas, Science Beyond Routine Flux Measurements: Products from the New and Expanding Database Carbon Fluxes Flux Spectra From Hours to Decade PhotoDegradation Mycorrhyzae Site MetaData Syntheses Leaf clumping, albedo and N Ecohydrology and Water Fluxes Water Use Efficiency Revisiting Budyko and Priestley-Taylor Continental/Global Upscaling of Evaporation in Time/Space Model Data Assimilation

Many Scales of Flux Variance Results demonstrate that the NEE and GEP wavelet spectra are similar amongst plant functional types (PFT) at weekly and shorter time scales, but significant divergence appeared among PFT at the biweekly and longer time scales, at which NEE and GEP are relatively less variable than climate. The RE spectra rarely differ among PFT across time scales. On average, RE spectra had greater low frequency (monthly to interannual) variability than NEE, GEP and climate….stress need to understand biology rather than climate at longer time scales The broader implications of this study suggest that, at shorter (hourly to weekly) time scales, the variability of C uptake across global ecosystems responds to climatic inputs in a similar matter regardless of PFT as revealed by the spectral analyses Ecosystem Respiration has more Energy at low frequencies than NEE and GPP Wavelet Spectrum emphasizes need for Long data record to disentangle biology from climate at multi-year time scales Data for Validating Models at long time scales Paul Stoy et al, Biogeosciences, to be submitted

What Happens to the Grass? The Soil is Too Dry to Sustain Respiration June October

Separating Plants and Soil: Ecosystem Minus Soil CO2 Efflux Summer Dry Period, Dead Grass and Dry Soil Baldocchi, Ma, Rutledge

PhotoDegradation: A Process Not in Coupled Carbon-Climate Models Baldocchi, Ma, Rutledge

Mycorrhizae Explain Different Connections between Climate and Carbon Flxues Interannual variations in ecosystem CO2 fluxes at arbuscular dominated sites were primarily controlled by changes in annual precipitation. Interannual variations in ecosystem CO2 fluxes for ectomycorrhizal dominated sites were primarily controlled by changes in mean annual temperature Across large geographical distances, interannual variations in ecosystem CO2 fluxes for ectomycorrhizal dominated sites were primarily controlled by changes in mean annual temperature. In contrast, variations in ecosystem CO2 fluxes at arbuscular dominated sites were primarily controlled by changes in annual precipitation. Our results support and complement the hypothesis that across large geographical distances, bioclimatic conditions strongly influence the distribution and dominance of AM and EM systems. These results provide the first large-scale assessment of terrestrial CO2 fluxes in multiple vegetation types classified according to dominant mycorrhizal association, and provide insights on potential effects of climate change on the global distribution of AM and EM systems. Vargas et al in press. New Phytologist

Albedo and Nutrition Hollinger et al 2009 Global Change Biology

Clumping is Ubitquitous And Must be Considered when Inverting Radiation transfer Ryu, Nilson, Kobayashi, Sonnentag, Baldocchi (to be submitted)

Water Use Efficiency, Coupling Water and Carbon Fluxes Beer et al. 2009. Global Biogeochemical Cycles

Test of the Budyko Curve with Evaporation Flux Measurements Evap Demand >> Precipitation Precipitation >> Evaporation, which Is energy limited Ppt/Rn

ESPM 129 Biometeorology

Explaining Budyko, part I Canopy Conductance scales with LAI, which scales with Water Budget and Nutrition

Priestley-Taylor and Surface Conductance Evaporation, normalized by Net Radiation, Diminishes with Reduced Conductance Plot from Chris Williams, Clark Univ

Optimizing Seasonality of Vcmax improves Prediction of Fluxes Wang et al, 2007 GCB

Incorporating Soil Evaporation Scheme in CABLE Improves Model Performance Williams et al. 2009. Biogeosciences

Using Flux Data to produce Global ET maps, V2 ET (mm H2O y-1) Fig.9 Global Evapotranspiration (ET) driven by interpolated MERRA meteorological data and 0.5º×0.6º MODIS data averaged from 2000 to 2003. Wenping Yuan

Using Flux data to produce Global ET maps, v3 Martin Jung/Markus Reichstein

And, WUE scales with LAI and Soil Moisture Beer et al. 2009. Global Biogeochemical Cycles

Albedo and Climate Forcing Heat absorbed Heat reflected Albedo and Climate Forcing Savannas Integrated annual error, or departure in the shortwave energy budget, for each site as derived from the calculated biome mean albedo. Grasslands Evergreen Deciduous Croplands Tom O’Hallaran

Global ET, 1989, ISLSCP, V1 Mean Global ET: 613 mm/y Van den Hurk et al 2003 JGR annual average land ET 1.28 kg m-2 d-1…467.2 mm/y; 649 mm/y Boslilovich; 560 mm from Jackson, land ET is 70,000 km3 and assuming 125 10^6 km2 land area Mean Global ET: 613 mm/y Fisher et al, Remote Sensing Environment, 2008