Results of the North American Results of the North American Carbon Program Site-level Interim Carbon Program Site-level Interim Synthesis Model Data Comparison Synthesis Model Data Comparison

(NACP Site Synthesis)(NACP Site Synthesis)

Ken Davis, Deborah Huntzinger, Dan Riciutto, Ken Davis, Deborah Huntzinger, Dan Riciutto, Kevin SchaeferKevin Schaefer, Peter , Peter Thornton, Deb Agarwal, Arlyn Andrews, Altaf Arain, Ian Baker, Dennis Thornton, Deb Agarwal, Arlyn Andrews, Altaf Arain, Ian Baker, Dennis

Baldocchi, Alan Barr, Paul Bolstad, Peter Curtis, Michael Dietze, Danilo Baldocchi, Alan Barr, Paul Bolstad, Peter Curtis, Michael Dietze, Danilo Dragoni, Mathias Goeckede, Robert Grant, Lianhong Gu, Dave Hollinger, Dragoni, Mathias Goeckede, Robert Grant, Lianhong Gu, Dave Hollinger,

Gabriel Katul, Tony King, Chris Kucharik, Beverly Law, Shugang Liu, Erandi Gabriel Katul, Tony King, Chris Kucharik, Beverly Law, Shugang Liu, Erandi Lokupitiya, Yiqi Luo, Roser Matamala, Russ Monson, J Munger, Walter Lokupitiya, Yiqi Luo, Roser Matamala, Russ Monson, J Munger, Walter

Oechel, Ram Oren, Philippe Peylin, David Price, Andrew Richardson, Bill Oechel, Ram Oren, Philippe Peylin, David Price, Andrew Richardson, Bill Riley, Michael Sprintsin, Hanqin Tian, Christina Tonitto, Margaret Torn, Riley, Michael Sprintsin, Hanqin Tian, Christina Tonitto, Margaret Torn,

Catharine van Ingen, Shashi Verma, Tao Wang, and Ensheng WengCatharine van Ingen, Shashi Verma, Tao Wang, and Ensheng Weng

Site Synthesis ObjectivesSite Synthesis Objectives

Are the various measurement and modeling Are the various measurement and modeling estimates of carbon fluxes consistent with each estimates of carbon fluxes consistent with each other - and if not, why?other - and if not, why?

• Quantify model and observation uncertaintyQuantify model and observation uncertainty• 47 flux tower sites; 25 models47 flux tower sites; 25 models• Gap-filled observed weatherGap-filled observed weather• Observed fluxes and ancillary biological dataObserved fluxes and ancillary biological data

• January 7-9: Full workshop at ORNLJanuary 7-9: Full workshop at ORNL

• February 17-20: NACP All-Investigators MtgFebruary 17-20: NACP All-Investigators Mtg

Flux Tower SitesFlux Tower Sites

Participating ModelsParticipating Models

• Results from Results from 15 models15 models

• 9 simulations 9 simulations per siteper site

Num Model Num Model

1 AgroIBIS 14 GTEC2 BEPS 15 ISOLSM3 Can-IBIS 16 LoTEC4 CLASS-CTEM 17 LoTEC_DA5 CLM-CASA' 18 LPJml6 CLM-CN 19 ORCHIDEE7 CN-CLASS 20 SiB38 DAYCENT 21 SiBCASA9 DLEM 22 SiBcrop

10 DNDC 23 SIPNET11 ecosys 24 SSiB212 ED2 25 TECO13 EDCM

Sources of UncertaintySources of Uncertainty

• ObservationsObservations• Random errorRandom error• Systematic error Systematic error

• ModelsModels• StructureStructure• ParameterParameter• Initial conditionsInitial conditions• Meteorological ForcingMeteorological Forcing• FootprintFootprint

Uncertainty at Inter-annual Time ScaleUncertainty at Inter-annual Time ScaleAnnual total NEE at Howland site, MaineAnnual total NEE at Howland site, Maine

Disturbance UncertaintyDisturbance UncertaintyORCHIDEE at 1850 burn site, ManitobaORCHIDEE at 1850 burn site, Manitoba

Uncertainty at Seasonal Time ScaleUncertainty at Seasonal Time ScaleAverage seasonal cycle at Howland site, MaineAverage seasonal cycle at Howland site, Maine

Uncertainty at Diurnal Time ScaleUncertainty at Diurnal Time Scale

Corn Year

Soybean Year

Mead rain-fed corn-soy rotation site (Nebraska)Mead rain-fed corn-soy rotation site (Nebraska)

Observed Flux Uncertainty Observed Flux Uncertainty

(Based on Richardson et al., 2006, Ag. For. Met. 136:1-18)

-35

239

BEPS

CNCLASS

ISOLSM

ecosys

SiBCASA

SiB

LoTEC_DA

can-ibis

ConclusionsConclusions

• Site Synthesis is a powerful Site Synthesis is a powerful dataset for model evaluation and dataset for model evaluation and improvementimprovement

• Next: rigorous statistical analysis Next: rigorous statistical analysis to quantify uncertaintyto quantify uncertainty