The MOD17A3HGF V6.1 product provides information about annual Gross and Net Primary Productivity (GPP and NPP) at 500m pixel resolution. Annual NPP is derived from the sum of all 8-day Net Photosynthesis(PSN) products (MOD17A2H) from the given year. The PSN value is the difference of the Gross Primary Productivity (GPP) …

The MOD17A2H Version 6 data product was decommissioned on July 31, 2023. Users are encouraged to use the MOD17A2H Version 6.1 data product.

The MOD17A2H Version 6 Gross Primary Productivity (GPP) product is a cumulative 8-day composite of values with 500 meter (m) pixel size based on the radiation use efficiency concept that can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. The data product includes information about GPP and Net Photosynthesis (PSN). The PSN band values are the GPP less the Maintenance Respiration (MR). The data product also contains a PSN Quality Control (QC) layer. The quality layer contains quality information for both the GPP and the PSN.

Known Issues * For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.

Improvements/Changes from Previous Versions * The product uses updated Biome Property look-up tables (BPLUT) and an updated version of the daily Global Modeling and Assimilation Office (GMAO) meteorological data. * The products are now generated at the native resolution of 500 m using the Moderate Resolution Imaging Spectroradiometer (MODIS) Leaf Area Index(LAI)/Fraction of Photosynthetically Active Radiation (FPAR) (MOD15A2H) 8-day composite at 500 m resolution.

The MODIS Gross Primary Production (GPP) CONUS dataset estimates GPP using MODIS Surface Reflectance for CONUS. GPP is the amount of carbon captured by plants in an ecosystem and is an essential component in the calculations of Net Primary Production (NPP). GPP is calculated using the MOD17 algorithm (see MOD17 User Guide) with MODIS Surface Reflectance, gridMET, and the National Land Cover Database.

The MOD17A2H V6.1 Gross Primary Productivity (GPP) product is a cumulative 8-day composite with a 500m pixel size. The product is based on the radiation-use efficiency concept and can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. Documentation: User's Guide Algorithm Theoretical Basis Document (ATBD) General Documentation

Gross Primary Productivity (GPP) represents the cumulative amount of carbon dioxide (CO2) assimilated by green plants through photosynthesis at specific time intervals and spatial scales. It is the main component of the carbon exchange between the terrestrial biosphere and the atmosphere, and has a major influence on global climate and terrestrial ecosystem functioning. Over the last two decades, the continuous and reliable collection of global land surface variables by EOS-MODIS, and the parallel development of the eddy-covariance flux tower network (FLUXNET) have enabled the integration of MODIS observations with tower measurements for the calibration and validation of remote sensing models to obtain global GPP estimates. Despite the significant progress and success to date, current remote sensing GPP models based on the light use efficiency (LUE) concept share several limitations, including the difficulty in accurately predicting LUE variability and the associated use of land cover m..., The eLUE Gross Primary Productivity (eLUE-GPP) is based on a simple yet ecologically sound ecosystem light use efficiency (eLUE) GPP model, using the more than two decades of global MODIS Enhanced Vegetation Index (EVI) product and the publicly available FLUXDATA2015 dataset, to generate a global GPP product (eLUE-GPP) from February 2000 to March 2024. The eLUE-GPP is available in both global and site scales and at various temporal and spatial resolutions. , , # eLUE-GPP (MODIS): A Global Gross Primary Productivity Product based on ecosystem light-use-efficiency model and MODIS EVI

https://doi.org/10.5061/dryad.v9s4mw74h

The eLUE Gross Primary Productivity (eLUE-GPP) is based on a simple yet ecologically sound ecosystem light use efficiency (eLUE) GPP model, using the more than two decades of global MODIS Enhanced Vegetation Index (EVI) product and the publicly available FLUXDATA2015 dataset, to generate a global GPP product (eLUE-GPP) from February 2000 to March 2024. The eLUE-GPP is available in both global and site scales and at various temporal and spatial resolutions.

Description of the data and file structure

The eLUE-GPP product has two Science Datasets, comprising GPP and GPP uncertainty. To reduce data storage size, the original values have been adjusted to integers. Users are advised to refer to the scaling factors for value restoration when using the data.

The eLUE-GPP dataset prov...

The MOD17A3HGF Version 6.1 product provides information about annual Gross and Net Primary Production (GPP and NPP) at 500 meter (m) pixel resolution. Annual Terra Moderate Resolution Imaging Spectroradiometer (MODIS) GPP and NPP is derived from the sum of all 8-day GPP Net Photosynthesis (PSN) products (MOD17A2H) from the given year. The PSN value is the difference of the GPP and the Maintenance Respiration (MR).The MOD17A3HGF will be generated at the end of each year when the entire yearly 8-day MOD15A2H is available. Hence, the gap-filled MOD17A3HGF is the improved MOD17, which has cleaned the poor-quality inputs from 8-day Leaf Area Index and Fraction of Photosynthetically Active Radiation (LAI/FPAR) based on the Quality Control (QC) label for every pixel. If any LAI/FPAR pixel did not meet the quality screening criteria, its value is determined through linear interpolation. However, users cannot get MOD17A3HGF in near-real time because it will be generated only at the end of a given year.Known Issues Operational and uncertainty issues are provided under Section 2 in the User Guide. For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.Improvements/Changes from Previous Versions The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).* The product uses Climatology LAI/FPAR as back up to the operational LAI/FPAR.

This dataset provides global gridded daily estimates of gross primary production (GPP) and uncertainties at 0.05-degree resolution for the period 2000-03-01 to the recent past. The GPP was derived from the MODerate-resolution Imaging Spectroradiometer (MODIS) instruments on the NASA Terra and Aqua satellites using the MCD43C4v006 Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectances (NBAR) product as input to neural networks that were used to globally upscale GPP estimated from selected FLUXNET 2015 eddy covariance tower sites. Additional data will be added periodically.

Abstract: MODIS Collection 6.1 8-day gap-filled Gross Primary Production (GPP) and Net Photosynthesis data on the MODIS sinusoidal grid are taken from the netCDF files produced at ICDC, for which the bit-encoded quality information given in the HDF-files was already decoded, and re-gridded to build a global map of grid-cell mean GPP and net photosynthesis and their variances on a global equirectangular climate modeling grid (CMG). Only those GPP or net photosynthesis values are used where i) the cloud flag indicates either clear sky or assumed clear sky, where the MODLAND quality is good and where the confidence flag suggests best quality or good quality data. The confidence flag is provided as a grid-cell mean rounded value with fractions of the five original flags being provided for convenience. Cloud conditions are included in form of the primary cloud flag and the fraction this primary cloud flag occupies among the valid 500 m sinusoidal grid grid cells. Two separate layers of the number of valid grid cells of the 500 m sinusoidal grid are given, one is for the geophysical data and one is for the flags.

TableOfContents: grid cell mean Gross_Primary_Production (GPP); grid cell mean Net Photosynthesis; GPP standard deviation over grid cell; Net Photosynthesis standard deviation over grid cell; number of used GPP or net photosynthesis values per grid cell; number of used confidence and quality flag values per grid cell; grid cell mean confidence flag; fraction of confidence flag 0 in grid cell; fraction of confidence flag 1 in grid cell; fraction of confidence flag 2 in grid cell; fraction of confidence flag 3 in grid cell; fraction of confidence flag 4 in grid cell; primary cloud flag; primary cloud flag fraction

Technical Info: dimension: 720 columns x 360 rows x unlimited; temporalExtent_startDate: 2000-02-18; temporalExtent_endDate: 2023-12-31; temporalResolution: 8-daily; spatialResolution: 0.5; spatialResolutionUnit: degrees; horizontalResolutionXdirection: 0.5; horizontalResolutionXdirectionUnit: degrees; horizontalResolutionYdirection: 0.5; horizontalResolutionYdirectionUnit: degrees; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: MODerate Resolution Spectroradiometer (MODIS); instrumentType: visible_to_infrared_spectroradiometer; instrumentLocation: Earth Observation Satellite (EOS) Terra; instrumentProvider: NOAA/NASA

Methods: [1] Running, S. W., and M. Zhao, Users Guide Daily GPP and Annual NPP (MOD17A2H/A3H) and Year-end Gap-Filled (MOD17A2HGF/A3HGF) Products NASA Earth Observing System MODIS Land Algorithm, (For Collection 6), Version 4.0, January 2, 2019; [2] Running, S. W., R. R. Nemani, F. A. Heinsch, M. Zhao, M. Reeves, and H. Hashimoto, A continuous satellite-derived measure of global terrestrial primary production. Bioscience, 54(6), 547-560, 2004; [3] Running, S. W., A measurable planetary boundary layer for the biosphere. Science, 337(6101), 1458-1459, 2012; [4] Zhao, M., F. A. Heinsch, R. R. Nemani, and S. W. Running, Improvements of the MODIS terrestrial gross and net primary production global data set. Remote Sensing of Environment, 95(2), 164-176, 2005

Units: Units for all variables (see TableOfContents): kg C m-2; kg C m-2; kg C m-2; kg C m-2; 1; 1; 1; percent; percent; percent; percent; percent; 1; percent

geoLocations: westBoundLongitude: -180.0 degrees East; eastBoundLongitude: 180.0 degrees East; southBoundLatitude: -90.0 degrees North; northBoundLatitude: 90.0 degrees North; geoLocationPlace: global on land

Size: (files are packed into one zip-archive per year)

• 2001-2021 and 2023: 46 files per year, each approximately 12975000 bytes
• 2000: 40 files of same size
• Data of the year 2022 are not published because data provided by LPDAAC seemed to be not reliable

Format: netCDF

DataSources:

Original data on sinusoidal grid tiles in hdf-format: https://doi.org/10.5067/MODIS/MOD17A2HGF.061 (last accessed: 2024-05-07), see also https://lpdaac.usgs.gov/products/mod17a2hgfv061/ (last accessed: 2024-05-07)

Data on sinusoidal grid tiles in netCDF format: https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html (last accessed: 2024-05-10) or https://doi.org/10.25592/uhhfdm.14463 (last accessed: 2024-06-25).

Contact: stefan.kern (at) uni-hamburg.de

Web page: https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html (last accessed: 2024-05-10)

This dataset provides global gridded daily estimates of gross primary production (GPP) and uncertainties at 0.5 deg latitude by 0.625 deg longitude resolution for the period March 2000 to present. The GPP is derived from MODerate-resolution Imaging Spectroradiometer (MODIS) instruments on NASA Terra and Aqua satellites. GPP is derived using the MODIS Nadir Bidirectional Reflectance Distribution Function (BRDF)-Adjusted Reflectances (NBAR) product, which is used as input to neural network models to globally upscale GPP estimated from selected collocated FLUXNET 2015 and OneFlux eddy covariance tower sites used for model training. Version 2.2 is the current version of the dataset.If you have any questions, please read the README document first and post your question to the NASA Earthdata Forum (forum.earthdata.nasa.gov) or email the GES DISC Help Desk (gsfc-dl-help-disc@mail.nasa.gov).

Abstract: MODIS Collection 6.1 yearly gap-filled Gross Primary Production (GPP) and Net Primary Production (NPP) data on the MODIS sinusoidal grid are taken from the netCDF files produced at ICDC, for which the bit-encoded quality information given in the HDF-files was already decoded, and re-gridded to build a global map of grid-cell mean GPP and NPP and their variances on a global equirectangular climate modeling grid (CMG). Only those GPP or NPP values are used where i) the cloud flag indicates either clear sky or assumed clear sky, where the MODLAND quality is good and where the confidence flag suggests best quality or good quality data. The confidence flag is provided as a grid-cell mean rounded value with fractions of the five original flags being provided for convenience. Cloud conditions are included in form of the primary cloud flag and the fraction this primary cloud flag occupies among the valid 500 m sinusoidal grid grid cells. Two separate layers of the number of valid grid cells of the 500 m sinusoidal grid are given, one is for the geophysical data and one is for the flags.

TableOfContents: grid cell mean Gross_Primary_Production (GPP); grid cell mean Net_Primary_Production (NPP); GPP standard deviation over grid cell; NPP standard deviation over grid cell; number of valid used GPP or NPP values per grid cell; number of valid used confidence and quality flag values per grid cell; grid cell mean confidence flag; fraction of confidence flag 0 in grid cell; fraction of confidence flag 1 in grid cell; fraction of confidence flag 2 in grid cell; fraction of confidence flag 3 in grid cell; fraction of confidence flag 4 in grid cell; primary cloud flag; primary cloud flag fraction

Technical Info: dimension: 720 columns x 360 rows x unlimited; temporalExtent_startDate: 2001-01-01; temporalExtent_endDate: 2023-12-31; temporalResolution: Yearly; spatialResolution: 0.5; spatialResolutionUnit: degrees; horizontalResolutionXdirection: 0.5; horizontalResolutionXdirectionUnit: degrees; horizontalResolutionYdirection: 0.5; horizontalResolutionYdirectionUnit: degrees; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: MODerate Resolution Spectroradiometer (MODIS); instrumentType: visible_to_infrared_spectroradiometer; instrumentLocation: Earth Observation Satellite (EOS) Terra; instrumentProvider: NOAA/NASA

Methods: [1] Running, S. W., and M. Zhao, Users Guide Daily GPP and Annual NPP (MOD17A2H/A3H) and Year-end Gap-Filled (MOD17A2HGF/A3HGF) Products NASA Earth Observing System MODIS Land Algorithm, (For Collection 6), Version 4.0, January 2, 2019; [2] Running, S. W., R. R. Nemani, F. A. Heinsch, M. Zhao, M. Reeves, and H. Hashimoto, A continuous satellite-derived measure of global terrestrial primary production. Bioscience, 54(6), 547-560, 2004; [3] Running, S. W., A measurable planetary boundary layer for the biosphere. Science, 337(6101), 1458-1459, 2012; [4] Zhao, M., F. A. Heinsch, R. R. Nemani, and S. W. Running, Improvements of the MODIS terrestrial gross and net primary production global data set. Remote Sensing of Environment, 95(2), 164-176, 2005

Units: Units for all variables (see TableOfContents): kg C m-2; kg C m-2; kg C m-2; kg C m-2; 1; 1; 1; percent; percent; percent; percent; percent; 1; percent

geoLocations: westBoundLongitude: -180.0 degrees East; eastBoundLongitude: 180.0 degrees East; southBoundLatitude: -90.0 degrees North; northBoundLatitude: 90.0 degrees North; geoLocationPlace: global on land

Size: (files are packed into one zip-archive)

• 2001-2023: 1 file per year, each approximately 12975000 bytes

Format: netCDF

DataSources:

Original data on sinusoidal grid tiles in hdf-format: https://doi.org/10.5067/MODIS/MOD17A3HGF.061 (last accessed: 2024-06-03), see also https://lpdaac.usgs.gov/products/mod17a3hgfv061/ (last accessed: 2024-06-03)

Data on sinusoidal grid tiles in netCDF format: https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html (last accessed: 2024-07-09) or https://doi.org/10.25592/uhhfdm.14633 (last accessed: 2024-07-09).

Contact: stefan.kern (at) uni-hamburg.de

Web page: https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html (last accessed: 2024-07-09)

The MYD17A3HGF V6.1 product provides information about annual Gross and Net Primary Productivity (GPP and NPP) at 500m pixel resolution. Annual NPP is derived from the sum of all 8-day Net Photosynthesis(PSN) products (MYD17A2H) from the given year. The PSN value is the difference of the Gross Primary Productivity (GPP) …

The MOD17A2HGF Version 6.1 Gross Primary Productivity (GPP) product is a cumulative 8-day composite of values with 500 meter (m) pixel size based on the radiation use efficiency concept that can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. The Terra Moderate Resolution Imaging Spectroradiometer (MODIS) data product includes information about GPP and Net Photosynthesis (PSN). The PSN band values are the GPP less the Maintenance Respiration (MR). The data product also contains a PSN Quality Control (QC) layer. The quality layer contains quality information for both the GPP and the PSN.The MOD17A2HGF will be generated at the end of each year when the entire yearly 8-day MOD15A2H is available. Hence, the gap-filled MOD17A2HGF is the improved MOD17, which has cleaned the poor-quality inputs from 8-day Leaf Area Index and Fraction of Photosynthetically Active Radiation (FPAR/LAI) based on the Quality Control (QC) label for every pixel. If any LAI/FPAR pixel did not meet the quality screening criteria, its value is determined through linear interpolation. However, users cannot get MOD17A2HGF in near-real time because it will be generated only at the end of a given year.Known Issues Operational and uncertainty issues are provided under Section 2 in the User Guide. For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.Improvements/Changes from Previous Versions The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).* The product uses Climatology LAI/FPAR as back up to the operational LAI/FPAR.

Net Primary Productivity (NPP) defines the rate at which all plants in an ecosystem produce net useful chemical energy. In other words, NPP is equal to the difference between the rate at which plants in an ecosystem produce useful chemical energy (or GPP), and the rate at which they expend some of that energy for respiration. The version-55 of the NPP product is produced by the Numerical Terradynamic Simulation Group (NTSG)/University of Montana (UMT). It corrects the problem with cloud-contaminated MODIS LAI-FPAR inputs to the MOD17 algorithm. The original, uncorrected datasets constitute the version-4 NPP products. For further details regarding the differences between the NTSG and NASA versions of this product, please consult the document referenced in the following news release: Terra MODIS GPP/NPP Products from NTSG/University of Montana Version-55 Terra/MODIS NPP products are validated to Stage-3; this means that its accuracy was assessed and uncertainties in the product were well-established via independent measurements made in a systematic and statistically robust way that represents global conditions. These data are deemed ready for use in science applications.

This data set provides data for MODIS-derived (1) gross primary productivity (GPP) for the years 2000-2010, (2) fraction of photosynthetically active radiation (fPAR) for the years 2003-2013, (3) sea surface temperature (SST) for the years 2003-2013, and (4) the NOAA-source Multivariate ENSO Index (MEI) data for the years 2003-2013 (as a measure of the El Nino/Southern Oscillation). The study areas were three transects on the Baja California Peninsula, Mexico, and the adjacent Pacific Ocean. The terrestrial transects, in order from North to South, West to East included Punta Colonet (three sites-PC1, PC2, PC3), Punta Abreojos (two sites-PA1, PA2), and Magdalena Bay (three sites-MB1, MB2, MB3).

The Terra/MODIS Gross Primary Productivity (GPP) product (MOD17A2) is a cumulative composite of GPP values based on the radiation-use efficiency concept that is potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. MOD17A2 is an 8-day composite at 1-km spatial resolution delivered as a gridded level-4 product in Sinusoidal projection.

The MODIS Adaptive Processing System (MODAPS) at the Goddard Spaceflight Center produces this GPP product. Users are encouraged to use the Numerical Terradynamic Simulation Group (NTSG)/University of Montana’s (UMT) version of this product available as version-55 from the LP DAAC. For more information, refer to the product details via the “Version 055” tab.

Version-5 and Version-55 Terra/MODIS GPP products are validated to Stage-3; this means that its accuracy was assessed and uncertainties in the product were well-established via independent measurements made in a systematic and statistically robust way that represents global conditions. These data are deemed ready for use in science applications.

V005 Data Set Characteristics: Area: ~10 degrees x 10 degrees lat/long Image Dimensions: 1200 x 1200 rows/columns File Size: ~0.2 MB Resolution: 1 kilometer Projection: Sinusoidal Data Format: HDF-EOS Science Data Sets (SDS HDF Layers): 3

This dataset contains estimated gross primary productivity (GPP), photosynthetically active radiation (PAR), soil adjusted near infrared reflectance of vegetation (SANIRv), the fraction of C4 crops in vegetation (fC4), and their uncertainties for the conterminous United States (CONUS) from 2000 to 2019. The daily estimates are SatelLite Only Photosynthesis Estimation (SLOPE) products at 250-m resolution. There are three distinct features of the GPP estimation algorithm: (1) SLOPE couples machine learning models with MODIS atmosphere and land products to accurately estimate PAR, (2) SLOPE couples gap-filling and filtering algorithms with surface reflectance acquired by both Terra and Aqua MODIS satellites to derive a soil-adjusted NIRv (SANIRv) dataset, and (3) SLOPE couples a temporal pattern recognition approach with a long-term Crop Data Layer (CDL) product to predict dynamic C4 crop fraction. PAR, SANIRv and C4 fraction are used to drive a parsimonious model with only two parameters to estimate GPP, along with a quantitative uncertainty, on a per-pixel and daily basis. The slope GPP product has an R2 = 0.84 and a root-mean-square error (RMSE) of 1.65 gC m-2 d-1.

The MYD17A2H Version 6.1 Gross Primary Productivity (GPP) product is a cumulative 8-day composite of values with 500 meter (m) pixel size based on the radiation use efficiency concept that can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. The Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) data product includes information about GPP and Net Photosynthesis (PSN). The PSN band values are the GPP minus the Maintenance Respiration (MR). The data product also contains a PSN Quality Control (QC) layer. The quality layer contains quality information for both the GPP and the PSN. Known Issues For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.Improvments/Changes from Previous Version The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. A polarization correction has been applied to the L1B Reflective Solar Bands (RSB). The product uses Climatology LAI/FPAR as back up to the operational LAI/FPAR.

The MYD17A3HGF Version 6.1 product provides information about annual Gross and Net Primary Production (GPP and NPP) at 500 meter (m) pixel resolution. Annual Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) GPP and NPP is derived from the sum of all 8-day GPP and Net Photosynthesis (PSN) products (MYD17A2H) from the given year. The PSN value is the difference of the GPP and the Maintenance Respiration (MR).The MYD17A3HGF will be generated at the end of each year when the entire yearly 8-day MYD15A2H is available. Hence, the gap-filled MYD17A3HGF is the improved MYD17, which has cleaned the poor-quality inputs from 8-day Leaf Area Index and Fraction of Photosynthetically Active Radiation (FPAR/LAI) based on the Quality Control (QC) label for every pixel. If any LAI/FPAR pixel did not meet the quality screening criteria, its value is determined through linear interpolation. However, users cannot get MYD17A3HGF in near-real time because it will be generated only at the end of a given year.Known Issues Operational and uncertainty issues are provided under Section 2 in the User Guide. For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.Improvments/Changes from Previous Version The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017. A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).* The product uses Climatology LAI/FPAR as back up to the operational LAI/FPAR.

The MYD17A2H Version 6 data product was decommissioned on July 31, 2023. Users are encouraged to use the MYD17A2H Version 6.1 data product.The MYD17A2H Version 6 Gross Primary Productivity (GPP) product is a cumulative 8-day composite of values with 500 meter (m) pixel size based on the radiation use efficiency concept that can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. The data product includes information about GPP and Net Photosynthesis (PSN). The PSN band values are the GPP minus the Maintenance Respiration (MR). The data product also contains a PSN Quality Control (QC) layer. The quality layer contains quality information for both the GPP and the PSN. Known Issues For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.Improvements/Changes from Previous Versions The product uses updated Biome Property Look-Up Tables (BPLUT) and an updated version of the daily Global Modeling and Assimilation Office (GMAO) meteorological data.* The products are now generated at the native resolution of 500 m using the Moderate Resolution Imaging Spectroradiometer (MODIS) Leaf Area Index (LAI)/Fraction of Photosynthetically Active Radiation (FPAR) (MYD15A2H) 8-day composite at 500 m resolution.

Abstract: MODIS Collection 6.1 yearly gap-filled Gross Primary Production (GPP) and Net Primary Production (NPP) data on the MODIS sinusoidal grid provided by LPDAAC: https://doi.org/10.5067/MODIS/MOD17A3HGF.061 (last accessed: 2024-07-09) are read together with their bit-encoded quality information from the HDF-files. The quality information is decoded and provided in form of separate flag layers in addition to the NPP data for each tile of the MODIS sinusoidal grid in netCDF file format (see https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html). For each tile, latitude and longitude information of the center of each 500 m x 500 m pixel is provided in a separate netCDF file.

TableOfContents: gross_primary_production (gpp); net_primary_production (npp); npp_quality_flag; npp_confidence_flag

Technical Info: dimension: 2400 columns x 2400 rows x unlimited; temporalExtent_startDate: 2001-01-01; temporalExtent_endDate: 2023-12-31; temporalResolution: yearly; spatialResolution: 500; spatialResolutionUnit: meter; horizontalResolutionXdirection: 500; horizontalResolutionXdirectionUnit: meter; horizontalResolutionYdirection: 500; horizontalResolutionYdirectionUnit: meter; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: MODerate Resolution Spectroradiometer (MODIS); instrumentType: visible_to_infrared_spectroradiometer; instrumentLocation: Earth Observation Satellite (EOS) Terra; instrumentProvider: NOAA/NASA

Methods: [1] Running, S. W., and M. Zhao, Users Guide Daily GPP and Annual NPP (MOD17A2H/A3H) and Year-end Gap-Filled (MOD17A2HGF/A3HGF) Products NASA Earth Observing System MODIS Land Algorithm, (For Collection 6), Version 4.0, January 2, 2019; [2] Running, S. W., R. R. Nemani, F. A. Heinsch, M. Zhao, M. Reeves, and H. Hashimoto, A continuous satellite-derived measure of global terrestrial primary production. Bioscience, 54(6), 547-560, 2004; [3] Running, S. W., A measurable planetary boundary layer for the biosphere. Science, 337(6101), 1458-1459, 2012; [4] Zhao, M., F. A. Heinsch, R. R. Nemani, and S. W. Running, Improvements of the MODIS terrestrial gross and net primary production global data set. Remote Sensing of Environment, 95(2), 164-176, 2005

Units: kg C m-2; kg C m-2;1; 1

geoLocations: westBoundLongitude: depends on tile; eastBoundLongitude: depends on tile; southBoundLatitude: depends on tile; northBoundLatitude: depends on tile; geoLocationPlace: global on land, see: https://modis-land.gsfc.nasa.gov/MODLAND_grid.html

Size: (files are packed into one zip-archive per year)

• 2001-2023: each zip file is about 2.1 Gbyte large; each single file approximately 34.5 Mbytes, for the number of tiles see https://modis-land.gsfc.nasa.gov/MODLAND_grid.html

Format: netCDF

DataSources:

Original data on sinusoidal grid tiles in hdf-format: https://doi.org/10.5067/MODIS/MOD17A3HGF.061 (last accessed: 2024-06-03), see also https://lpdaac.usgs.gov/products/mod17a3hgfv061/ (last accessed: 2024-06-03)

Contact: stefan.kern (at) uni-hamburg.de

Web page: https://www.cen.uni-hamburg.de/en/icdc/data/land/modis-primaryproduction.html (last accessed: 2024-07-08)