CarboExtreme Database

Variables and formats available

Continuous Level2 data

Level2 data are original data submitted by the PI and checked/filtered only for out-of-range values or clearly wrong data. The variables available are listed in the table here below and are provided as ASCII file with missing values reported as -9999 and timestamp indicating the end of the averaging period. The file produced has in the first line the variables codes.

Drag a column header and drop it here to group by that column
AlbAlbedo %1
APARAbsorbed PAR (400-700 nm)umol m-2 s-12
CH4Methane concentrationppb3
CO2CO2 concentration ppm4
FcCO2 flux umolCO2 m-2 s-16
Fc_CMBNEE measured using transparent chambersumolCO2 m-2 s-27
FCH4Methane (CH4) fluxnmol m-2 s-18
FCH4_CMBMethane flux measured using chambersnmol m-2 s-19
Fetch70Fetch at which footprint cumulated probability is 70%m10
Fetch90Fetch at which footprint cumulated probability is 90%m11
FetchmaxFetch at which footprint cumulated probability is maximum m12
FN2ONitrous oxide (N2O) flux nmol m-2 s-113
FN2O_CMBNitrous oxide flux measured using chambersnmol m-2 s-114
FNONitric oxide (NO) flux nmol m-2 s-115
FNO2Nitrogen dioxide (NO2) flux nmol m-2 s-116
FO3Ozone (O3) flux nmol m-2 s-117
GSoil heat flux W m-218
HSensible heat fluxW m-219
H2OWater vapour concentrationmmol mol-120
LELatent heat flux W m-221
LeafwLeaf wetness%22
LWinIncoming Longwave radiation (in the range from 4 to 50 micron)W m-223
LWoutOutgoing Longwave radiation (in the range from 4 to 50 micron)W m-224
MO_lengthMonin-Obhukov length m25
MWSMaximum wind speed m s-126
NDVINormalized Difference Vegetation Index adimensional27
NEE_piNet Ecosystem Exchange submitted by PI umolCO2 m-2 s-128
NetRadNet radiation (including SW and LW components)W m-229
NONO concentration ppb30
NO2NO2 concentration ppb31
O3O3concentration ppb32
PPrecipitation mm33
P_snowSnowfall – snow precipitationmm (or water)35
PaAtmospheric pressure Kpa36
PPFDPhotosynthetic Photon Flux Density (400-700 nm)umol m-2 s-137
PPFDbcBelow canopy PPFD (400-700 nm)umol m-2 s-138
PPFDdDiffuse incoming PPFD (400-700 nm)umol m-2 s-139
PPFDrReflected PPFD (400-700 nm)umol m-2 s-140
PRIPhotochemical Reflectance Index adimensional41
QcFcQuality check - CO2 flux (0=high, 1=medium, 2=low quality)adimensional42
QcFootQuality check -footprint (0=Fetch70 outside target area; 1=can be used, 0=measurement with footprint contaminations)adimensional43
QcHQuality check - sensible heat flux (0=high, 1=medium, 2=low quality)adimensional44
QcLEQuality check - latent heat flux (0=high, 1=medium, 2=low quality)adimensional45
QcTauQuality check - momentum flux (0=high, 1=medium, 2=low quality)adimensional46
R_UVAUVA radiation W m-247
R_UVBUVB radiation W m-248
RHRelative humidity %49
RhetHeterotrophic respiration flux umolCO2 m-2 s-150
RsSoil CO2 efflux umolCO2 m-2 s-151
SaSensible heat storage fluxW m-253
Sap_dtDifference of probes temperature for sapflow measurements°C54
SapflowSapflowmmolH2O m-2 s-155
SbHeat storage in biomassW m-256
ScCO2 storage fluxumolCO2 m-2 s-157
Sigma_vStandard deviation of lateral velocity fluctuations (cross main-wind direction after coordinates rotation)m s-158
Sigma_wStandard deviation of vertical velocity fluctuations m s-159
SNOWDSnow depth cm60
Spec_in_529incoming radiation at 529 nm umol m-2 s-161
Spec_in_568incoming radiation at 568 nm umol m-2 s-162
Spec_nir_inincoming radiation (infra-red band)umol m-2 s-163
Spec_nir_outoutgoing radiation (infra-red band)umol m-2 s-164
Spec_out_529outgoing radiation at 529 nm umol m-2 s-165
Spec_out_568outgoing radiation at 568 nm umol m-2 s-166
Spec_red_inincoming radiation (red band)umol m-2 s-167
Spec_red_outoutgoing radiation (red band)umol m-2 s-168
StemflowStemflow mm69
SwLatent heat storage fluxW m-270
SWbcBelow canopy incoming short wave radiationW m-271
SWCSoil water content%72
SWdifDiffuse incoming Shortwave radiation (in the range from 0.3 to 4.5 micron)W m-273
SWinIncoming Shortwave radiation (in the range from 0.3 to 4.5 micron)W m-274
SWoutOutgoing Shortwave radiation (in the range from 0.3 to 4.5 micron)W m-275
TaAir temperature °C76
TauMomentum flux Kg m-1 s-277
TbcTemperature below canopy °C78
TboleBole temperature°C79
TcCanopy temperature°C80
TFThroughfall mm81
TsSoil temperature°C82
TRTree transpirationml hr-183
ustarFriction velocitym s-184
WDWind directionDecimal degree85
WSWind speed m s-186
WTDWater table depth cm87
ZLStability parameter adimensional88
FNO_CMBNO flux measured using chambersnmol m-2 s-189
FNO2_CMBNO2 flux measured using chambersnmol m-2 s-190

Level3 and Level4 data

The Level3 data are standard files with a selected number of variables with NEE calculated (Fc+Sc) and quality flags related to spikes and ustar filtering. Only flags are added and the data are not changed. The instead Level4 data are filtered, gapfilled and partitioned and aggregated at different time resolutions, from halfhourly to yearly.

The data are provided as ASCII files and as Matlab files. It is possible to download an example of Level3 and Level4 data, including the data description, here below:

Download a Level3 data file

Download a Level4 data file

Ancillary data

The ancillary data available are listed in the table below. These variables have a number of qualifiers that provide additional information (e.g. SOIL_C has as qualifier the uncertainty, the measurement depth, the reference date, possible comments…) and that are automatically added to the output file; a list of the existing qualifiers for each variable is available here. Ancillary data are provided in ASCII files with six columns:

  • idVar: it is an integer number that identifies variables and qualifiers that are linked (see below the example)

  • Variable: it is the variable code as in the table below

  • Qualifier: a parameter related to the variable (e.g. the error or the method). It is "VALUE" when the variable value is reported.

  • Value: the value of the variable or variable+qualifier; can be numeric or text depending of the nature of the qualifier

  • Date: measurement or reference date in the format YYYYMMDD can be also only YYYYMM or YYYY when needed

  • Time: time of the measurement, when relevant, in the format HHMM

In the example below it is explained how to use and interpret the idVar; supposing to have two measurements of LAI, the same day, but with different methodologies. The Qualifiers are the Value, Sigma, Technique and Comment and are present in both the measurements. The idVar helps to identify which Value, Sigma and Comment are related to the two methodologies used. In the example, the records with idVar = 16 are related to the LI-2000 technique while the LAI measured using hemispherical photos are identified by the idVar = 17. An example of Ancillary data file is available here.

Example of the idVar use






16,LAI,COMMENT,10 measurement points in the footprint,20100621,-9999




17,LAI,COMMENT,3 pictures in the footprint,20100621,-9999


Drag a column header and drop it here to group by that column
AG_BIOMASS_CFAboveground biomass of crops foliage. Dry weight of foliagegC m-2
AG_BIOMASS_CHAboveground biomass of crops harvest. Dry weight of harvest materials such as fruitgC m-2
AG_BIOMASS_CTAboveground biomass of crops total. Includes live foliage and harvest materialsgC m-2
AG_BIOMASS_NWTAboveground biomass of non-woody plants. Dry weight of plants including plants and forbs. Grassland sites report the total above ground biomass. Forest sites report any non-woody plants.gC m-2
AG_BIOMASS_SFAboveground biomass of shrub foliage. Dry weight of live foliagegC m-2
AG_BIOMASS_STAboveground biomass of shrubs totalgC m-2
AG_BIOMASS_SWAboveground biomass of shrub wood. Dry weight of stems and branchesgC m-2
AG_BIOMASS_TFAboveground biomass of tree foliage. Dry weight of live foliage.gC m-2
AG_BIOMASS_TTAboveground biomass trees total. Dry weight live foliage, stems, and branches.gC m-2
AG_BIOMASS_TWAboveground biomass of tree wood. Dry weight of live stems and branches.gC m-2
AG_PROD_CFAboveground production of crops foliage. Includes live foliage only. gC m-2 yr-1
AG_PROD_CHAboveground production of crops harvest. Includes agricultural crops harvest materials such as friutgC m-2 yr-1
AG_PROD_CTAboveground production of crops total. Includes foliage and harvest materialsgC m-2 yr-1
AG_PROD_NWTAboveground production of non-woody plants. Dry weight of plants including plants and forbs. Grass sites report the total above ground biomass. Forest sites report any non-woody plants.gC m-2 yr-1
AG_PROD_SFAboveground production of shrub foliage. Includes foliage onlygC m-2 yr-1
AG_PROD_STAboveground production of shrub totalgC m-2 yr-1
AG_PROD_SWAboveground production of shrub wood. Inlcudes stems and branchesgC m-2 yr-1
AG_PROD_TFAboveground production of tree foliage. Includes overstory foliage only.gC m-2 yr-1
AG_PROD_TTAboveground production of tree total. Includes overstory foliage, stems, and branches.gC m-2 yr-1
AG_PROD_TWAboveground production of tree wood. Includes overstory stems and branches.gC m-2 yr-1
ASAMean stand age in yearsyears
CLAY_PERCClay content%
CR_BIOMASSCoarse root biomass (live)gC m-2
CR_PRODCoarse root productiongC m-2 yr-1
CROP_RESIDCrop residue. Dead mass dry weightgC m-2 yr-1
CWDCoarse woody debris. Includes debris with diameter >10 cmgC m-2
FOL_NFoliage nitrogen concentrationgN/100g foliar mass
FOL_CFoliage carbon concentrationgC/100g foliar mass
FR_BIOMASSFine root biomass (live)gC m-2
FR_PRODFine root productiongC m-2 yr-1
FWDFine woody debris. Includes debris with diameters 1cm - 10cmgC m-2
HEIGHTCCanopy heightm
LAILeaf Area Index. Averaged over the tower footprint. Calculated as m2 half-surface area leaf per m2 ground. Report green leaf LAI and not total leaf LAI.m2 m-2
LAI_DODeciduous overstory Leaf Area Index. Averaged over the tower footprintm2 m-2
LAI_EOEvergreen overstory Leaf Area Index. Averaged over the tower footprintm2 m-2
LAI_UUnderstory Leaf Area Indexm2 m-2
LIT_MASSLitter mass. Dry weight including litter and twigs < 1 cm diameter.gC m-2
LIT_NLitter nitrogen concentrationgN/100g litter
LIT_CLitter carbon concentrationgC/100g litter
LIT_PRODLitterfall. Leaf litter and twigs < 1cm diameter. Sampled periodically through the year, dried and weighed and summed over yeargC m-2 yr-1
LMALeaf mass per unit leaf areagC m-2
MSAMaximum stand age. Calculated as the mean age of the oldest 10% of treesyears
NEPNet ecosystem production. Computed from biological measurementsgC m-2 yr-1
ROCK_PERCRock content%
ROOT_NRoot nitrogen concentrationgN/100g
ROOT_CRoot carbon concentrationgC/100g
RsSite specific mean soil CO2 effluxumol m-2 s-1
RT_BIOMASSTotal root biomass (live)gC m-2
RT_PRODTotal root productiongC m-2 yr-1
SAND_PERCSand content%
SILT_PERCSilt content%
SNAGMass of standing dead trees. Dry weightgC m-2
SOIL_BDSoil bulk density%
SOIL_CSoil organic carbon. Percent by mass.Kg m-2
SOIL_DEPTHSoil depthm
SOIL_NSoil nitrogen contentKg m-2
SOIL_PHSoil PH. Total soil PH as CaCl2decimal number
SOIL_WATER_CAPSoil water holding capacitymm
SPP_OOverstory dominant speciesNRCS code or scientific
SPP_UUnderstory dominant speciesNRCS code or scientific
ST_MASSStump mass. Dry weightgC m-2
WOOD_INCRWood radial incrementmm
WOOD_NWoody tissue nitrogen concentrationgN/100g dry weight
WOOD_CWoody tissue carbon concentrationgC/100g dry weight