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NACP Regional: Gridded 1-deg Observation Data and Biosphere and Inverse Model Outputs

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Revision Date: May 2, 2013

Summary:

This data set contains standardized gridded observation data, terrestrial biosphere model output data, and inverse model simulations of carbon flux parameters that were used in the North American Carbon Program (NACP) Regional Synthesis activities. The data set provides five observation data files (MODIS GPP, MODIS NPP, FIA forest biomass/forest area, NASS crop NPP, and NASS agricultural land fraction) and simulation results from 18 terrestrial biosphere models (TBM) (28 variables; 114 files) and seven inverse models (IM) (two variables; 8 files).

To produce this data set, the NACP Modeling and Synthesis Thematic Data Center (MAST-DC) resampled original model simulation results and observation measurement data to 1-degree spatial resolution for North American region, interpolated into monthly or yearly temporal resolution, and reformatted into Climate and Forecast (CF) convention compatible netCDF format.

This data set is related to two other processed regional data sets (i.e., NACP Regional: Supplemental Gridded Observations, Biosphere and Inverse Model Outputs; and NACP Regional: National Greenhouse Gas Inventories and Aggregated Gridded Model Data) and the originally-submitted NACP Regional: Original Observation Data and Biosphere and Inverse Model Outputs.

Detailed descriptions of observation data, TBMs, and IMs can be found in the companion file Regional-Description_of_Observations_and_Models.pdf.

MAST-DC was a component of the NACP (www.nacarbon.org) designed to support NACP by providing data products and data management services needed for modeling and synthesis activities. The overall objective of MAST-DC was to provide data management support to NACP investigators and agencies performing modeling and synthesis activities.

Data and Documentation Access:

Get Data: http//:daac.ornl.gov/cgi-bin/dsviewer.pl?ds_id=1157

Companion Documentation for this Data Set:

Model Characteristics Overview and References: NACP_Model_Characteristics.pdf

Related Data Products:

 

 

Data Citation:

Cite this data set as follows:

Wei, Y., W.M. Post, R.B. Cook, D.N. Huntzinger, P.E. Thornton, A.R. Jacobson, I. Baker, J. Chen, F. Chevallier, F.M. Hoffman, A. Jain, S. Liu, R. Lokupitiya, D.A. McGuire, A. Michalak, G.G. Moisen, R.P. Neilson, P. Peylin, C. Potter, B. Poulter, D. Price, J. Randerson, C. Rödenbeck,  H. Tian, E. Tomelleri, G. van der Werf, N. Viovy, T.O. West, J. Xiao, N. Zeng, and M. Zhao. 2013. NACP Regional: Gridded 1-deg Observation Data and Biosphere and Inverse Model Outputs. Data set. Available on-line [http://daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. http://dx.doi.org/10.3334/ORNLDAAC/1157

 

Table of Contents:

1. Data Set Overview:

Project: North American Carbon Program (NACP)

The NACP (Denning et al., 2005; Wofsy and Harriss, 2002) is a multidisciplinary research program to obtain scientific understanding of North America's carbon sources and sinks and of changes in carbon stocks needed to meet societal concerns and to provide tools for decision makers. Successful execution of the NACP has required an unprecedented level of coordination among observational, experimental, and modeling efforts regarding terrestrial, oceanic, atmospheric, and human components. The program has relied upon a rich and diverse array of existing observational networks, monitoring sites, and experimental field studies in North America and its adjacent oceans. It is supported by a number of different federal agencies through a variety of intramural and extramural funding mechanisms and award instruments.

NACP and MAST-DC organized several synthesis activities to evaluate and inter-compare biosphere model outputs and observation data at local to continental scales for the time period of 2000 through 2005. The synthesis activities have included three component studies, each conducted on different spatial scales and producing numerous data products: (1) site-level analyses that examined process-based model estimates and observations at over 30 AmeriFlux and Fluxnet-Canada tower sites across North America; (2) a regional, mid-continent intensive study centered in the agricultural regions of the United States and focused on comparing inventory-based estimates of net carbon exchange with those from atmospheric inversions; and (3) a regional and continental synthesis evaluating model estimates against each other and available inventory-based estimates across North America. A number of other NACP syntheses were conducted, including ones focusing on non-CO2 greenhouse gases, the impact of disturbance on carbon exchange, and coastal carbon dynamics. The Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) is the archive for the NACP synthesis data products.

This data set contains part of the third NACP synthesis product described above: regional analyses. It provides standardized 1-degree gridded observation (OM) data, terrestrial biosphere model (TBM) output data, and inverse model (IM) simulations that were processed by MAST-DC and used in the NACP Regional Synthesis activities (Table 1). The data set includes five (5) OM data files (MODIS GPP, MODIS NPP, FIA forest biomass/forest area, NASS crop NPP, and NASS agricultural land fraction), 114 TBM data files, and eight (8) IM data files. To produce this data set, the originally-submitted data were resampled to 1-degree spatial resolution for North American region, interpolated into monthly or yearly temporal resolution, and reformatted into Climate and Forecast (CF) convention compatible netCDF format (Table 2).

This data set is related to two other processed regional data sets (i.e., supplemental observation data and biosphere and inverse model outputs; and national greenhouse gas (GHG) inventories and model outputs aggregated by GHG inventory zones) and the originally-submitted observation data and model outputs (see Related Data Products above). Detailed descriptions of observation data, TBM, and IM models can be found in a separate document: Regional-Description_of_Observations_and_Models.pdf.



Table 1. Contributors

Last NameFirst Name Organization Email Role
WeiYaxing ORNL weiy@ornl.gov MAST-DC
PostWilfred M. University of Tennessee wmp@ornl.gov MAST-DC
CookRobert B. ORNL cookrb@ornl.gov MAST-DC
HuntzingerDeborah N. Northern Arizona University deborah.huntzinger@nau.edu Synthesis Lead
ThorntonPeter E. ORNL thorntonpe@ornl.gov MAST-DC, CLM-CN
JacobsonAndy NOAA andy.jacobson@noaa.gov Synthesis Lead, CarbonTracker
BakerIan Colorado State University baker@atmos.colostate.edu SIB3.1
ChenJing University of Toronto chenj@geog.utoronto.ca BEPS
ChevallierFrederic LSCE Frederic.Chevallier@lsce.ipsl.fr LSCE no.2
HoffmanForrest ORNL forrest@climatemodeling.org CLM-CASA
JainAtul University of Illinois at Urbana-Champaign jain@atmos.uiuc.edu ISAM
LiuShuguang USGS sliu@usgs.gov EC-LUE
LokupitiyaRavi Colorado State University ravi@atmos.colostate.edu CSU no.1
McGuireDavid A. University of Alaska Fairbanks ffadm@uaf.edu TEM6
MichalakAnna Stanford University michalak@stanford.edu Michigan Geostatistical
MoisenGretchen G. USDA Forest Service gmoisen@fs.fed.us U.S. Forest Biomass
NeilsonRonald P. USDA Forest Service rneilson@fs.fed.us MC1
PeylinPhilippe LSCE Philippe.Peylin@lsce.ipsl.fr
LSCE no.1
PotterChris NASA Ames Research Center chris.potter@nasa.gov NASA-CASA
PoulterBen Potsdam Institute for Climate Impact Research ben.poulter@pik-potsdam.de LPJmL
PriceDavid Canadian Forest Service dprice@nrcan.gc.ca
Can-IBIS
RandersonJim University of California Irvine jranders@uci.edu CASA-Transcom
RödenbeckChristian Max Planck Institute for Biogeochemistry christian.roedenbeck@bgc-jena.mpg.de Jena
TianHanqin Auburn University tianhan@auburn.edu DLEM
TomelleriEnrico Max Planck Institute for Biogeochemistry etomell@bgc-jena.mpg.de
MOD17-plus
van der WerfGuido University Amsterdam guido.van.der.werf@falw.vu.nl CASA-GFEDv2
ViovyNicolas LSCE viovy@lsce.ipsl.fr
ORCHIDEE
WestTristram O. PNNL tristram.west@pnnl.gov
Crop NPP
XiaoJingfeng University of New Hampshire j.xiao@unh.edu EC-MOD
ZengNing University of Maryland at College Park zeng@atmos.umd.edu VEGAS
ZhaoMaosheng University of Montana zhao@ntsg.umt.edu MODIS GPP/NPP


Table 2. List of Observation Measurements and Models in the Gridded 1-degree Analysis

OBSERVATION MEASUREMENTS
Observation Data Short Name
MODIS MOD17A2 Gross Primary Production (GPP) MODIS GPP
MODIS MOD17A3 Net Primary Production (NPP) MODIS NPP
Conterminous U.S. Forest Biomass/Forest Area FIA Forest Biomass
Conterminous U.S. Crop Net Primary Production (NPP)/Agricultural Land Fraction NASS Crop NPP
TERRESTRIAL BIOSPHERE MODELS
Prognostic Models Short Name
Canadian Integrated BIosphere Simulator Can-IBIS
Community Land Model with CASA (i01.55_q15) CLM-CASA
Community Land Model with Carbon&Nitrogen (i01.57_q15) CLM-CN
Dynamic Land Ecosystem Model DLEM
Integrated Science Assessment Model ISAM
Lund-Potsdam-Jena managed Land model LPJmL
MC1 Dynamic Vegetation Model MC1
Organizing Carbon and Hydrology in Dynamic Ecosystems model (v1.0) ORCHIDEE
Simple Biosphere model version 3.1 SiB3.1
Terrestrial Ecosystem Model version 6 TEM6
Vegetation Global Atmosphere and Soil model VEGAS
Diagnostic Models Short Name
Boreal Ecosystems Productivity Simulator BEPS
Carnegie-Ames-Stanford-Approach model (Transcom version) CASA-Transcom
Carnegie-Ames-Stanford-Approach model(Global Fire Emissions Database v 2 version) CASA-GFEDv2
NASA-Carnegie-Ames-Stanford-Approach model NASA-CASA
Eddy-Covariance Light Use Efficiency model EC-LUE
Eddy-Covariance model with MODIS EC-MOD
MOD17-plus MOD17+
INVERSE MODELS
Inversion Models Short Name
CarbonTracker CarbonTracker
University of Toronto Nested Global model UToronto
Michigan Geostatistical model Michigan Geostatistical
Laboratoire des Sciences du Climat et de l'Environnement (LSCE) no.1 (Peylin-LSCE) model LSCE-no1 (Peylin)
Laboratoire des Sciences du Climat et de l'Environnement (LSCE) no.2 (Chevallier-LSCE) model LSCE-no2 (Chevalier)
JENA CO2 Inverse model Jena (Rodenbeck)
CSU no. 1 (MLEF-PCTM) model CSU-no1 (MLEF-PCTM)

Table 3. Data Packages Summary

Data Set Sub Category Variables Files File Formats
Standardized Gridded Observation and Model Output Data Observation Measurements (OM) 6 (GPP, NPP, forest biomass, forest area, crop NPP, agricultural land fraction) 5 netCDF
Terrestrial Biosphere Model (TBM) Outputs 28114 netCDF
Inverse Model (IM) Outputs 2 (NEE, FF)8 netCDF

2. Data Description:

This data set contains a total of 127 data files (5 OM data files, 114 TBM output data files, and 8 IM output data files). The data have been resampled by ORNL DAAC to a standard 1-degree spatial resolution for North American region, interpolated into monthly or yearly temporal resolution, converted to a standardard measurement unit (generally, kg C/m2/month or year), and reformatted into CF convention compatible netCDF format.

Site boundaries: (All latitude and longitude given in decimal degrees)

Site (Region) Westernmost Longitude Easternmost Longitude Northernmost Latitude Southernmost Latitude
North America -170 -50 84 10

2.1. Spatial Coverage

Site: North America

2.2. Spatial Resolution

1 degree x 1 degree

2.3. Spatial Coordinate Reference System

Sphere-based Geographic Lat/Lon. In CF-compatible netCDF files, it’s defined as:
char crs;
   crs:grid_mapping_name = "latitude_longitude";
   crs:semi_major_axis = 6370997.0f;
   crs:inverse_flattening = 0.0f;

2.4. Temporal Coverage

Varies (range: 1990-2007). See Tables 2-4.

2.5. Temporal Resolution

Monthly or yearly with a few "one time" observations. See Tables 4-6.

2.6. Time Variable:

Units: “days since 1990-01-01 UTC”

Calendar: “noleap”

2.7. Data File Information

All of the data files are Climate & Forecast (CF) convention 1.0 compatible netCDF v3 formatted. Spatial resolution for all files is 1 degree x 1 degree. Spatial extent and temporal resolution and extent vary as noted. Missing values are designated by the value -9999.0. For each .zip file there is also an accompanying .txt companion file which contains file charactersitics and processing steps to convert the files into different formats.

Table 4. Observation Measurements (OM) Data Files


FILE NAMES TEMPORAL RESOLUTION TEMPORAL EXTENT SPATIAL EXTENT UNITS VARIABLE
COMPRESSED FILE NAMES * UNCOMPRESSED DATA FILE NAMES
OM_MODIS_GPP_Standardized.zip OM_MODIS_GPP_1d.nc Monthly 2000-2006 NA kg C/m^2/month Gross Primary Production (MODIS GPP)
OM_MODIS_NPP_Standardized.zip OM_MODIS_NPP_1d.nc Yearly 2000-2006 NA kg C/m^2/yr Net Primary Production (MODIS NPP)
OM_FIA_Biomass_Standardized.zip OM_FIA_Biomass_1d.nc One time ~2000 CONUS kg C/m^2_of_forest Forest biomass
m^2 Forest area
OM_NASS_Crop_Standardized.zip OM_NASS_CropNPP_1d.nc Yearly 2001-2005 CONUS mg C/total area of each 1-degree grid cell/year NASS Crop NPP
OM_NASS_AgPercent_1d.nc percentage (%) of agricultural land in each 1-degree grid cell Agricultural land fraction

Notes: CONUS = conterminous United States. NA = North America.

Table 5. Terrestrial Biosphere Model (TBM) Output Data Files



FILE NAMES TEMPORAL RESOLUTION TEMPORAL EXTENT SPATIAL EXTENT UNITS VARIABLE
COMPRESSED FILE NAMES * UNCOMPRESSED DATA FILE NAMES
TBM_BEPS_Standardized.zip TBM_BEPS_GPP_1d.nc Monthly 2000-2004 NA kg C/m^2/mo Gross primary production (GPP)
TBM_BEPS_NEE_1d.nc Net ecosystem exchange (NEE) (derived from -1*NEP)
TBM_BEPS_NEP_1d.nc Net ecosystem production (NEP)
TBM_BEPS_NPP_1d.nc Net primary production (NPP)
TBM_BEPS_Rh_1d.nc Heterotrophic respiration (Rh) (derived from NPP-NEP)
TBM_CASA-GFEDv2_Standardized.zip TBM_CASA-GFEDv2_CFire_1d.nc Monthly 2000-2005 NA kg C/m^2/mo Fire emisssions (derived from NEEF-NEE)
TBM_CASA-GFEDv2_GPP_1d.nc GPP
TBM_CASA-GFEDv2_NEE_1d.nc NEE
TBM_CASA-GFEDv2_NEEF_1d.nc Net ecosystem exchange with fire emissions (NEEF)
TBM_CASA-GFEDv2_R_1d.nc Total respiration (R)
TBM_CASA-Transcom_Standardized.zipTBM_CASA-Transcom_NEE_1d.nc Monthly 2002-2003 NA kg C/m^2/mo NEE
TBM_CLM-CASA_Standardized.zip TBM_CLM-CASA_CWDC_1d_i01.55casa_q15.nc Monthly 1990-2004 NA kg C/m^2 Coarse woody debris carbon (CWDC)
TBM_CLM-CASA_FROOTC_1d_i01.55casa_q15.nc Fine root carbon (FROOTC)
TBM_CLM-CASA_GPP_1d_i01.55casa_q15.nc kg C/m^2/mo GPP
TBM_CLM-CASA_HR_1d_i01.55casa_q15.nc Heterotrophic respiration (HR)
TBM_CLM-CASA_landfrac_1d_i01.55casa_q15.nc One time One time

Range: 0-1

Land fraction
TBM_CLM-CASA_LEAFC_1d_i01.55casa_q15.nc Monthly 1990-2004 kg C/m^2 Leaf carbon (LEAFC)
TBM_CLM-CASA_LITTERC_1d_i01.55casa_q15.nc Litter carbon
TBM_CLM-CASA_NEE_1d_i01.55casa_q15.nc kg C/m^2/mo NEE
TBM_CLM-CASA_NEP_1d_i01.55casa_q15.nc NEP
TBM_CLM-CASA_NPP_1d_i01.55casa_q15.nc NPP
TBM_CLM-CASA_SOILC_1d_i01.55casa_q15.nc kg C/m^2 Total soil organic matter carbon
TBM_CLM-CASA_TLAI_1d_i01.55casa_q15.nc >dimensionless ratio (m^2/m^2) Total projected leaf area index
TBM_CLM-CASA_VegC_1d_i01.55casa_q15.nc kg C/m^2 Vegetation carbon (derived from LEAFC+WOODC+FROOTC)
TBM_CLM-CASA_WOODC_1d_i01.55casa_q15.nc Wood carbon (WOODC)
TBM_CLM-CN_Standardized.zip TBM_CLM-CN_CWDC_1d_i01.57cn_q15.nc Monthly 1990-2004 NA kg C/m^2 Coarse woody debris carbon (CWDC)
TBM_CLM-CN_FROOTC_1d_i01.57cn_q15.nc Fine root carbon (FROOTC)
TBM_CLM-CN_GPP_1d_i01.57cn_q15.nc kg C/m^2/mo GPP
TBM_CLM-CN_HR_1d_i01.57cn_q15.nc Heterotrophic respiration (HR)
TBM_CLM-CN_landfrac_1d_i01.57cn_q15.nc One time One time Range: 0-1 Land fraction
TBM_CLM-CN_LEAFC_1d_i01.57cn_q15.nc Monthly 1990-2004 kg C/m^2 Leaf carbon (LEAFC)
TBM_CLM-CN_LITTERC_1d_i01.57cn_q15.nc Litter carbon
TBM_CLM-CN_NEE_1d_i01.57cn_q15.nc kg C/m^2/mo NEE
TBM_CLM-CN_NEP_1d_i01.57cn_q15.nc NEP
TBM_CLM-CN_NPP_1d_i01.57cn_q15.nc NPP
TBM_CLM-CN_SOILC_1d_i01.57cn_q15.nc kg C/m^2 Total soil organic matter carbon
TBM_CLM-CN_TLAI_1d_i01.57cn_q15.nc dimensionless ratio (m^2/m^2) Total projected leaf area index
TBM_CLM-CN_TOTVEGC_1d_i01.57cn_q15.nc kg C/m^2 Total vegetation carbon (derived from LEAFC+WOODC+FROOTC)
TBM_CLM-CN_WOODC_1d_i01.57cn_q15.nc Wood carbon (WOODC)
TBM_Can-IBIS_Standardized.zip TBM_Can-IBIS_CBiomass_1d.nc Monthly 2000-2005 NA kg C/m^2/year Biomass
TBM_Can-IBIS_CSoil_1d.nc Soil carbon
TBM_Can-IBIS_GPP_1d.nc kg C/m^2/mo GPP
TBM_Can-IBIS_NEE_1d.nc NEE (derived from -1*NEP)
TBM_Can-IBIS_NEP_1d.nc NEP
TBM_Can-IBIS_NPP_1d.nc NPP
TBM_Can-IBIS_Ra_1d.nc Autotrophic respiration (Ra)
TBM_Can-IBIS_Rh_1d.nc Heterotrophic respiration (Rh)
TBM_DLEM_Standardized.zip TBM_DLEM_GPP_1d.nc Monthly 2000-2005 NA kg C/m^2/mo GPP
TBM_DLEM_NEE_1d.nc NEE
TBM_DLEM_NPP_1d.nc NPP
TBM_DLEM_Ra_1d.nc Autotrophic respiration (Ra)
TBM_DLEM_Rh_1d.nc Heterotrophic respiration (Rh)
TBM_DLEM_TotLivBiom_1d.nc kg C/m^2 Total live biomass carbon (monthly mean total carbon content of the living biomass including heartwood)
TBM_DLEM_TotSoilCarb_1d.nc Monthly mean total soil carbon density
TBM_EC-LUE_Standardized.zipTBM_EC-LUE_GPP_1d.nc Monthly 2004-2005 NA kg C/m^2/mo GPP
TBM_EC-MOD_Standardized.zipTBM_EC-MOD_GPP_1d.nc Monthly 2001-2006 NA kg C/m^2/mo GPP
TBM_EC-MOD_NEE_1d.nc NEE
TBM_ISAM_Standardized.zip TBM_ISAM_NEE_1d.nc Monthly2000-2007 NA kg C/m^2/mo NEE
TBM_ISAM_NPP_1d.nc NPP
TBM_ISAM_Rh_1d.nc Heterotrophic respiration (Rh)
TBM_LPJmL_Standardized.zip TBM_LPJmL_ANEE_1d.nc Annual 1990-2006 NA kg C/m^2/year Annual net ecosystem exchange (derived from monthly NEE)
TBM_LPJmL_ANEEF_1d.nc Annual net ecosystem exchange with fire emissions (derived from ANEE+FIRE)
TBM_LPJmL_FIRE_1d.nc Fire emissions
TBM_LPJmL_GPP_1d.nc Monthly kg C/m^2/mo GPP
TBM_LPJmL_LITC_1d.nc Annual kg C/m^2 Litter carbon
TBM_LPJmL_NEE_1d.nc Monthly kg C/m^2/mo NEE
TBM_LPJmL_NPP_1d.nc NPP
TBM_LPJmL_RA_1d.nc Autotrophic respiration (RA)
TBM_LPJmL_RH_1d.nc Heterotrophic respiration (RH)
TBM_LPJmL_SOILC_1d.nc Annual kg C/m^2 Soil carbon
TBM_LPJmL_VEGC_1d.nc Live vegetation carbon
TBM_MC1_Standardized.zip TBM_MC1_BioCons_1d.nc Monthly 2000-2007 CONUS kg C/m^2/mo Biomass consumed
TBM_MC1_NBP_1d.nc Net biome production
TBM_MC1_NEE_1d.nc NEE
TBM_MC1_NEEF_1d.nc Net ecosystem exchange with fire emissions (derived from NEE+BioCons)
TBM_MC1_NPP_1d.nc NPP
TBM_MC1_RespH_1d.nc Heterotrophic respiration (respH)
TBM_MC1_TotLivBiom_1d.nc kg C/m^2 Total living biomass
TBM_MC1_TSLC_1d.nc Total soil carbon
TBM_MOD17-plus_Standardized.zip TBM_MOD17-plus_GPP_1d.nc Monthly2000-2005 NA kg C/m^2/mo GPP
TBM_MOD17-plus_NEE_1d.nc NEE (derived from Reco-GPP)
TBM_MOD17-plus_Reco_1d.nc Ecosystem respiration (Reco)
TBM_NASA-CASA_Standardized.zip TBM_NASA-CASA_NEE_1d.nc Monthly 2001-2004 CONUS kg C/m^2/mo NEE (derived from -1*NEP)
TBM_NASA-CASA_NEP_1d.nc NEP
TBM_NASA-CASA_NPP_1d.nc NPP
TBM_NASA-CASA_Rh_1d.nc Heterotrophic respiration (Rh) (derived from NPP-NEP)
TBM_ORCHIDEE_Standardized.zip TBM_ORCHIDEE_CO2FLUX_1d_v1.0.nc Monthly 2001-2007 NA kg C/m^2/mo CO2 flux
TBM_ORCHIDEE_GPP_1d_v1.0.nc GPP
TBM_ORCHIDEE_GROWTH_RESP_1d_v1.0.nc Growth respiration
TBM_ORCHIDEE_HET_RESP_1d_v1.0.nc Heterotrophic respiration (HET_RESP)
TBM_ORCHIDEE_LAI_1d_v1.0.nc dimensionless ratio (m^2/m^2) Leaf area index
TBM_ORCHIDEE_NPP_1d_v1.0.nc kg C/m^2/mo NPP
TBM_SiB3_Standardized.zip TBM_SiB3_NEE_1d.nc Monthly 2000-2005 NA kg C/m^2/mo NEE
TBM_TEM6_Standardized.zip TBM_TEM6_NACP_FireEmissions_1d.nc Monthly 2000-2006 NA>45o kg C/m^2/mo Fire emissions (derived from NCE-NEE)
TBM_TEM6_NACP_GPP_1d.nc GPP
TBM_TEM6_NACP_NCE_1d.nc Net exchange of carbon from the land to the atmosphere = Equals to NEEF (fire emissions included)
TBM_TEM6_NACP_NECB_1d.nc Net ecosystem carbon balance from the land to the atmosphere
TBM_TEM6_NACP_NEE_1d.nc NEE (derived from Rh-NPP)
TBM_TEM6_NACP_NPP_1d.nc NPP
TBM_TEM6_NACP_RH_1d.nc Heterotrophic respiration (RH)
TBM_TEM6_NACP_SOILC_1d.nc kg C/m^2 Total soil carbon
TBM_TEM6_NACP_VEGC_1d.nc Total vegetation carbon above and below ground
TBM_VEGAS_Standardized.zip TBM_VEGAS_cb_1d.nc Monthly2000-2007 NA kg C/m^2 Total biomass carbon
TBM_VEGAS_cfire_1d.nc

kg C/m^2/mo

Fire emissions
TBM_VEGAS_cleaf_1d.nc kg C/m^2 Leaf carbon
TBM_VEGAS_csoil_1d.nc Soil carbon
TBM_VEGAS_cvege_1d.nc Total vegetation carbon
TBM_VEGAS_evap_1d.nc W/m^2 Evapotranspiration
TBM_VEGAS_GPP_1d.nc kg C/m^2/mo GPP
TBM_VEGAS_LAI_1d.nc

dimensionless ratio (m^2/m^2)

Leaf area index
TBM_VEGAS_NEE_1d.nc kg C/m^2/mo NEE (fire emissions included)
TBM_VEGAS_NEP_1d.nc NEP
TBM_VEGAS_NPP_1d.nc NPP
TBM_VEGAS_Ra_1d.nc Autotrophic respiration (Ra)
TBM_VEGAS_Rh_1d.nc Heterotrophic respiration (Rh)

Notes: CONUS = conterminous United States. NA = North America. GPP = Gross Primary Production. NEE = Net Ecosystem Exchange. NEP = Net Ecosystem Production. NPP = Net Primary Production.

Table 6. Inverse Model (IM) Output Data Files

FILE NAMES TEMPORAL RESOLUTION TEMPORAL EXTENT SPATIAL EXTENT UNITS VARIABLE
COMPRESSED FILE NAMES * UNCOMPRESSED DATA FILE NAMES
IM_CarbonTracker_Standardized.zip IM_CarbonTracker_NEE_1d.nc Monthly 2000-2007 NA kg C/m^2/mo Net ecosystem exchange (NEE)
IM_CSU-no1_Standardized.zip IM_CSU-no1_FF_1d.nc Monthly 2003-2004 NA kg C/m^2/mo Fossil Fuel emissions (FF)
IM_CSU-no1_NEE_1d.nc NEE
IM_JENA_Standardized.zip IM_JENA_NEE_1d.nc Monthly 2001-2007 NA

kg C/m^2/mo

NEE
IM_LCSE-no1_Standardized.zip IM_LCSE-no1_NEE_1d.nc Monthly 2000-2004 NA kg C/m^2/mo NEE
IM_LCSE-no2_Standardized.zip IM_LCSE-no2_NEE_1d.nc Monthly 2000-2006 NA kg C/m^2/mo NEE
IM_Michigan-Geostatistical_Standardized.zip IM_Michigan-Geostatistical_NEE_1d.nc Monthly 1997-2001 NA kg C/m^2/mo NEE
IM_UToronto_Standardized.zip IM_UToronto_NEE_1d.nc Monthly 1997-2001 NA kg C/m^2/mo NEE

Notes:  NA = North America.

2.8. Observation Data and Model Output Variables

Table 7. List of Observation Data and Model Output Variables

Short Name Units Long Name Temporal Resolution Models
Gross Primary Productivity (GPP)
GPP kg C m-2 month-1 gross primary production monthly MODIS GPP, BEPS, Can-IBIS, CASA-GFEDv2, CLM-CASA, CLM-CN, DLEM, EC-LUE, EC-MOD, LPJmL, MOD17-plus, ORCHIDEE (v1.0), TEM6, VEGAS, OSU-BGC
Net Primary Productivity  (NPP)
NPP kg C m-2 month-1 net primary production monthly MODIS NPP, BEPS, Can-IBIS, CLM-CASA, CLM-CN, ISAM, LPJmL, MC1, NASA-CASA, ORCHIDEE (v1.0), TEM6, VEGAS, DLEM
NPPCrop kg C m-2 month-1 net primary production crop monthly ORCHIDEE (v2.1)
CropNPP MgC y-1 crop NPP annual NASS CropNPP
Net Ecosystem Exchange  (NEE)
NEE kg C m-2 month-1 net ecosystem exchange monthly BEPS, Can-IBIS, CASA-GFEDv2, CLM-CASA, CLM-CN, EC-MOD, ISAM, LPJmL, MC1, MOD17-plus, NASA-CASA, SiB3, TEM6, VEGAS, CASA-Transcom, DLEM, CarbonTracker, UToronto, LSCE-no1, LSCE-no2, JENA, CSU-no1, Michigan-Geostatistical
CO2FLUX kg C m-2 month-1 co2 flux monthly ORCHIDEE (v1.0)
ANEE kg C m-2 year-1 annual net ecosystem exchange yearly LPJmL
NEEF kg C m-2 month-1 net ecosystem exchange with
fire emissions
monthly MC1, CASA-GFEDv2
ANEEF kg C m-2 year-1 annual net ecosystem exchange with fire emissions yearly  LPJmL
Net Ecosystem Production
NEP kg C m-2 month-1 net ecosystem production monthly BEPS, Can-IBIS, CLM-CASA, CLM-CM,
NASA-CASA, VEGAS
Total Respiration 
R kg C m-2 month-1 respiration monthly CASA-GFEDv2
Reco kg C m-2 month-1 ecosystem respiration monthly MOD17-plus
Autotrophic Respiration 
Ra kg C m-2 month-1 autotrophic respiration monthly Can-IBIS, VEGAS, DLEM
RA kg C m-2 month-1 autotrophic respiration monthly LPJmL
Heterotrophic Respiration
Rh kg C m-2 month-1 heterotrophic respiration monthly BEPS, Can-IBIS, ISAM, NASA-CASA,
VEGAS, DLEM
HR kg C m-2 month-1 heterotrophic respiration monthly CLM-CASA, CLM-CN
RH kg C m-2 month-1 heterotrophic respiration monthly LPJmL, TEM6
RespH kg C m-2 month-1 heterotrophic respiration monthly MC1
HetResp kg C m-2 month-1 heterotrophic respiration monthly ORCHIDEE (v1.0)
Fire Emissions
Cfire kg C m-2 month-1 fire emissions monthly CASA-GFEDv2
cfire kg C m-2 month-1 fire emissions monthly VEGAS
FIRE kg C m-2 year-1 fire emissions yearly LPJmL
BioCons kg C m-2 month-1 biomass consumed monthly MC1
FireEmissions kg C m-2 month-1 fire emissions monthly TEM6
Total Living Biomass
TotLivBiom kg C m-2 monthly mean total carbon content
of the living biomass including heartwood
monthly DLEM
TotLivBiom kg C m-2 total living biomass monthly MC1
CBiomass kg C m-2 biomass yearly Can-IBIS
cb kg C m-2 total biomass carbon monthly VEGAS
Biomass kg C m-2 forest biomass one time FIA Forest Biomass
Total Soil Carbon: Total soil and litter carbon content vertically integrated over the entire soil column
TotSoilCarb kg C m-2 monthly mean total soil carbon density monthly DLEM
CSoil kg C m-2 soil carbon yearly Can-IBIS
SOILC kg C m-2 total soil organic matter C monthly CLM-CASA, CLM-CN
SOILC kg C m-2 total soil carbon monthly TEM6
SOILC kg C m-2 soil carbon yearly LPJmL
TSLC kg C m-2 total soil carbon monthly MC1
csoil kg C m-2 soil carbon monthly VEGAS
Leaf Area Index
LAI (-) leaf area index monthly ORCHIDEE (v1.0), VEGAS
TLAI (-) total projected leaf area index monthly CLM-CASA, CLM-CN
Evapevapotranspiration (ET)
evap W m-2 evapotranspiration   VEGAS
Coarse Woody Debris Carbon
 CWDC kg C m-2 coarse woody debris C monthly CLM-CASA, CLM-CN
Wood Carbon
WOODC kg C m-2 wood C monthly CLM-CASA, CLM-CN
Fine Root Carbon
FROOTC kg C m-2 fine root C monthly CLM-CASA, CLM-CN
Land Fraction
landfrac (-) land fraction monthly CLM-CASA, CLM-CN
Leaf Carbon
LEAFC kg C m-2 leaf C monthly CLM-CASA, CLM-CN
cleaf kg C m-2 leaf carbon monthly VEGAS
Litter Carbon
LITTERC kg C m-2 litter C monthly CLM-CASA, CLM-CN
LITC kg C m-2 litter carbon yearly LPJmL
Vegetation Carbon
VegC kg C m-2 vegetation C monthly CLM-CASA
cvege kg C m-2 total vegetation carbon monthly VEGAS
VEGC kg C m-2 live vegetation carbon yearly LPJmL
VEGC kg C m-2 total vegetation above and below ground monthly TEM6
TOTVEGC kg C m-2 total vegetation carbon monthly CLM-CN
Net Biome Production
NBP kg C m-2 month-1 net biome production monthly MC1
Growth Respiration
GROWTH_RESP kg C m-2 month-1 growth respiration monthly ORCHIDEE (v1.0)
Net Carbon Exchange
NCE kg C m-2 month-1 net exchange of C from the land to
the atmosphere
monthly TEM6
Net Ecosystem Carbon Balance
NECB kg C m-2 month-1 net ecosystem C balance from the land to the atmosphere monthly TEM6

 

2.9. Companion File Information

Table 8. Companion Files

FILE NAME DESCRIPTION
Regional-Description_of_Observations_and_Models.pdf Overview of observation measurement data and terrestrial biosphere and inverse models, including descriptions, sources, contacts, and a comprehensive reference list
NACP_Model_Characteristics.pdf Overview of process descriptions in participating TBMs and boundary conditions and driver data used in participating TBMs with a comprehensive reference list
NACP_Model_Metadata_Survey_Results.pdf Metadata for TBMs Intercomparison: Site Model Data Comparison and Regional Model Data Comparison: Survey Results

 

3. Data Application and Derivation:

This data product contributes to a multidisciplinary research program to obtain scientific understanding of North America's carbon sources and sinks and of changes in carbon stocks needed to meet societal concerns and to provide tools for decision makers. It is part of a NACP regional and continental synthesis to evaluate and inter-compare models and observation measurements across North America. This work provides a valuable assessment of the current status of terrestrial carbon modeling in North America by bringing together model estimates that incorporate a wide range of modeling choices and input data. This work can also be used to compare the model results to different observational data products.

4. Quality Assessment:

This data set provides the standardized, gridded observation measurements and model simulation output results that MAST-DC produced from the original data submissions. The differences (range) in estimates of regional land-atmosphere carbon fluxes in the data files in this data set appear to be driven by a combination of factors.

The participating models differ from each other because they are based on different simplifying assumptions and use different approaches (forward vs. inverse) and modeling strategies (detailed process, statistical, or observation based). They also differ structurally in how they represent the processes controlling carbon exchange between the land and atmosphere (e.g., representation of photosynthesis), in their input or environmental driver data (e.g., land cover, climate variables) and the temporal variability of those data, in their initial conditions, and in the parameter values used within their varying process descriptions. The gridded observation data also differ with regards to biome type, acquisition methods, spatial coverage and resolution, and temporal coverage and resolution. These varying approaches result in a large degree of variability in estimates of regional land-atmosphere carbon fluxes.

The variability in carbon flux estimates highlights the need for further analysis through the use of model runs following a common simulation protocol, to isolate the influences of model formulation, structure, and assumptions on flux estimates. A more formal model-data comparison is required to more definitively quantify the impact of model formulation and supporting and driver data on the accuracy of the simulation model outputs. Such efforts are underway by NACP, requiring substantial technical support for model participation, development of consistent and optimal environmental driver data sets, a unified intercomparison protocol, as well as coordination of the intercomparison effort across research groups. These NACP projects include (1) working to understand how model formulation and model choices impact overall model performance through the use of detailed simulation protocol and controlled input environmental driver data (e.g., Schwalm et al., 2010) and (2) the Multi-Scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP), which directly builds of the NACP regional synthesis products presented here.

5. Data Acquisition Materials and Methods:

Original model simulation results and observation measurement data were resampled by ORNL DAAC to a standard 1-degree spatial resolution for North American region, interpolated into monthly or yearly temporal resolution, converted to a standardard measurement unit (generally, kg C/m2/month or year), and reformatted into CF convention compatible netCDF format. [Note: FIA forest biomass/area data are also provided at half degree resolution.]

Information about the specific data processing steps taken by MAST-DC are available by contacting the Data Center as indicated below.

6. Data Access:

This data set is available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Data Archive:

Web Site: http://daac.ornl.gov

Contact for Data Center Access Information:

E-mail: uso@daac.ornl.gov
Telephone: +1 (865) 241-3952

7. References:

Denning, A.S., et al. 2005. Science implementation strategy for the North American Carbon Program: A Report of the NACP Implementation Strategy Group of the U.S. Carbon Cycle Interagency Working Group. U.S. Carbon Cycle Science Program, Washington, DC. 68 pp.

Huntzinger, D.N., W.M. Post, Y. Wei, A.M. Michalak, T.O. West, A.R. Jacobson, I.T. Baker, J.M. Chen, K.J. Davis, D.J. Hayes, F.M. Hoffman, A.K. Jain, S. Liu, A.D. McGuire, R.P. Neilson, C. Potter, B. Poulter, D. Price, B.M. Raczka, H.Q. Tian, P. Thornton, E. Tomelleri, N. Viovy, J. Xiao, W. Yuan, N. Zeng, M. Zhao, and R. Cook. 2012. North American Carbon Program (NACP) regional interim synthesis: Terrestrial biospheric model intercomparison. Ecological Modelling 232(10): 144-157. doi:10.1016/j.ecolmodel.2012.02.004

Schwalm, C. R., et al. 2010. A model-data intercomparison of CO2 exchange across North America: Results from the North American Carbon Program site synthesis. J. Geophys. Res. 115: G00H05. doi:10.1029/2009JG001229.

Wofsy, S.C., and R.C. Harriss. 2002. The North American Carbon Program (NACP). Report of the NACP Committee of the U.S. Interagency Carbon Cycle Science Program. U.S. Global Change Research Program, Washington, DC. 56 pp.

Additional Sources of Information:

Please see the Reference section in the Regional-Description_of_Observations_and_Models.pdf document for publications related to the observation measurements, TBMs, and IMs used in this study.