FLUXNET, Status and Future Dennis Baldocchi Deb Agarwal Dario Papale NACP/AmeriFlux: New Orleans, LA, Feb 2011
Outline • Overview, Status and Sustenance, Baldocchi • Data System, Project Management, Agarwal • Value-Added Products, Papale • Gap-Filling, Flux Partitioning
Developing a System that is Everywhere, All of the Time forestinventoryplot century Forest/soil inventories Landsurface remote sensing decade Eddycovariancetowers talltowerobser- vatories remote sensingof CO2 year Temporal scale month week day hour local 0.1 1 10 100 1000 10 000 global Countries plot/site EU Spatial scale [km] Credit: Markus Reichstein, MPI
Challenges • To Sustain and Grow the Network that ask and answer Network-Scale Questions • To sample representative Climates and Biomes • To sample representative Disturbance Classes • Detect trends in Fluxes as Climate and Land Use Changes • Validate and Parameterize New Generation of Land Surface-Atmosphere Exchange Models • Serve as Critical Partner in Machine Learning Approaches to Flux Upscaling with Satellite Remote Sensing
Status of Global Network, 500+ Sites Being Registered Does not mean Active or Contributing Data
Growth in Africa, Australia and Asia, Sustenance in Brazil and Europe Decline in Canada and US Voids in India and Latin America
Important to Sustain Networks Because Big Science Questions Being Answered by Flux Networks • What is Global GPP? • 123 +/- 8 PgC/ y, Beer et al, Science • What is Global ET? • 65,000 km3/y, Jung et al. 2010, Nature • What is Global Year to Year Variability in GPP and NEE? • What Emergent Scale Properties arise at the Ecosystem Scale? • Rain-induced respiration Pulses, modulated by photodegradation • Diffuse Light Enhances LUE • Q10 are static and Respiration Decrease with Heat and Drought
Big Network Issues Facing Flux Networks in 2011 • How can we Sustain the Network? • How many Stations are Enough? • Where do we need new Stations? • How can we encourage Scientists to Participate, submit data and Open the Data to the Wider Science Community, with Benefits to ALL?
How Many Towers are Needed to Yield Stable Network Statistics? Is this Sample, Statistically Representative of a Biome, Continent or Globe?
What is Interannual Variability of Fluxes, sampled with the Network and Detection Limit? Can We ask this Question with a Sparse Network, if the Representativeness of each Tower is Larger than its Geographical Domain? This Analysis Would Suggest Global Metabolism is Invariant with Time, like the Solar Constant
Increasing the Size of the Network Reduces the Sampling Error, but in an Asymptotic Manner Limit in the Precision of NEE Change that can be detected if Upscaled Globally: +/- 20 gC m-2 y-1 ~ 2 PgC/y = 2 1015gC/y Can We Truly Detect Year-Year Variations in Fluxes with a Sparse Network? Errors that sound Small at one scale may be Huge at another..
FLUXNET Over represents GPP in Temperate, Mid-Productive Ecosystems; Under-represents GPP in Semi-Arid, low-productive and Tropical, High Productive Regions
Flux Networks, Alone, May Not be Able to Answer Important Global Questions But Flux Networks, In Partnership with Satellite Remote Sensing and New Generation of Machine Learning Algorithms May.. Path to Rich Future of New Scale Emergent Science
Regional Maps for Carbon Markets Disturbances Climate Anomalies
Evaluation of upscaled global Evapotranspiration • Map of mean Evapotranspiration from 1982-2008 • Predicted vs. Observed ET at FLUXNET sites (10-fold cross-validation from MTE training) • Corroboration aganist river catchment water balances • Comparison against GSWP-2 land surface model ensemble (16 models) stratified according to bioclimatic zones Jung et al. 2010 Nature
Community Building/OutReach Newsletter: FluxLetter Young Scientist Forums Workshops La Thuile, 2007 Asilomar, 2009 Berkeley, 2011
FLUXNET and Remote Sensing Open Workshop: Towards Upscaling Flux Information from Towers to the Globe • June 7-9, 2011, Berkeley, CA • Open Registration, but limited to 150 total.. • To learn more about the workshop and to register, visit: • http://nature.berkeley.edu/biometlab/fluxnet2011/fluxwkshp.html • Registration/Lunches/Coffee are free • There are limited travel funds available for graduate students, postdocs and workshop speakers.
Highlights/ Successes • Papers in Science and Nature • Beer et al; Mahecha et al; Jung et al. • Explosion of Synthesis Papers • New Generation of Spatial Upscaling Papers • Xiao et al; Jung et al; Beer et al; Mu et al. • Citation Count is Growing
Concluding Comments • We Must Continue to Work Together to Address Important and Contemporary Questions Pertaining to Earth System Science and Climate Change • A Large and Growing Community of Modelers and Synthesis Scientists are Dependent Upon our Data • Data are Produced with Govt Support, so it is the Ethical Duty • Protections are in place to protect Data, PIs and Students in the Short Term, 1-2 years • It should be the obligation of PIs to Release Data Sets in the Long-Run, e.g. Older Datasets, to Advance Science