NLDAS Vegetation Class/Mask

NLDAS Vegetation Class & Mask Illustrations and Datasets


THIS is the official NLDAS vegetation data page. Another vegetation page is available which contains datasets which may be useful to some users, but they do not play a role in NLDAS simulations.

The land mask and land cover classification map used for NLDAS is the University of Maryland's UMD Land Cover Classification. Imagery from AVHRR satellites from between 1981 and 1994 were used to create a static land cover map. The 14-class UMD map at 1-km was used for NLDAS. If more than 50% of all UMD 1-km pixels within each 1/8th-degree NLDAS grid box are identified as water, then the NLDAS land mask is defined as water for that grid box, and no NLDAS output is available for that 1/8th-degree grid box.

Data from an early version of Boston University's MODIS land cover type product, which uses a 17-type IGBP (International Geosphere-Biosphere Programme) classification is also presented on the NLDAS grid, but is not currently used by the NLDAS project.

The NON-ADJUSTED UMD and IGBP 1/8th-degree datasets are based solely on the 1-km UMD and IGBP vegetation datasets. Fractional coverage amounts were arrived at by first counting up the number of occurrences of a particular type of vegetation (1-km scale) within an 1/8th-degree grid box, and then dividing this number by the total number of 1-km pixels in an 1/8th-degree box.

The ADJUSTED 1/8th-degree datasets are based both on the 1-km UMD or IGBP data, and on a 1-km fractional vegetation coverage dataset from Bob Dickinson's group which contains the maximum vegetation fraction over a seasonal cycle. Instead of simply dividing the total number of occurrences of a particular type of vegetation (at 1-km) in an 1/8th-degree box by the total number of 1-km pixels in that box, each occurrence of the vegetation type is first multiplied by Dickinson's fractional coverage at the 1-km scale. These fractional 1-km vegetation values are then summed up to 1/8th-degree scale to create an adjusted number of occurrences of that particular type of vegetation in an 1/8th-degree box (now a real number, not an integer). The bare soil fractions of each pixel are also kept track of and added up with the pixels specified in the UMD and IGBP datasets as "Bare Soil" or "Barren" to create a total count of "Bare Soil" or "Barren" 1-km pixels in an 1/8th-degree box (again, now a real number, not an integer). As before, these numbers are then divided by the total number of 1-km pixels in the 1/8th-degree box to arrive at the final product - fractional coverage of the particular type of vegetation and "Bare Soil" or "Barren" land in an 1/8th-degree grid box. The use of Dickinson's dataset has the effect of creating larger percentages of "Bare Soil" and "Barren" areas (which can be seen in the plots below).

The first four or five plots of each dataset display the percent of each NLDAS grid box occupied by each of the 14 UMD or 17 IGBP vegetation categories and were constructed as described above. In order to create the land/water masks on this page, the percent coverage of water in each NLDAS grid box was used such that grid boxes made up of more than 50% water were assigned a "water" value of 0 in the NLDAS land/water mask, while all other grid boxes received a "land" value of 1. The fractional coverage values in all four vegetation datasets enabled the creation of the NLDAS predominant vegetation datasets. These datasets contain, for each vegetation classification scheme, the four most predominant vegetation types in each 1/8th-degree grid box. While the "predominant vegetation type" plots and datasets have each been rectified to the unified land/water mask created from the original UMD data, all of the other plots, and all of the other data files are based on masks from their respective datasets. Therefore, the native land/water mask plot are provided for each dataset.

NLDAS Unified Mask

The image and data files in this section are different forms of the NLDAS unified mask and are based on non-adjusted UMD vegetation data. Other land/water masks are located on this site and are each based on their respective vegetation datasets (i.e. UMD, adjusted UMD, IGBP, adjusted IGBP); however, only the unified (non-adjusted UMD) mask contained in this section should be used in NLDAS modeling efforts.

image of NLDAS unified land/water mask
NLDAS unified land/water mask (JPEG, 22kb)

NLDAS UMD Illustrations

Categories 0-3
UMD Vegetation Fractional Coverages (Categories 0-3) (JPEG, 112kb)

Categories 4-7
UMD Vegetation Fractional Coverages (Categories 4-7) (JPEG, 140kb)

Categories 8-11
UMD Vegetation Fractional Coverages (Categories 8-11) (JPEG, 144kb)

Categories 12-13
UMD Vegetation Fractional Coverages (Categories 12-13) (JPEG, 68kb)

UMD Land/Water Mask
UMD Land/Water Mask (JPEG, 56kb)

Predominant Vegetation Types
NLDAS UMD Predominant Vegetation Types (JPEG, 224kb)

NLDAS UMD Datasets

  • (Binary) - NLDAS_UMDpredomveg.bin
    This file contains the predominant UMD vegetation type in binary format. You may find NLDAS_UMDpredomveg.F90 helpful to read the file, as well as a NLDAS_UMDpredomveg.ctl GrADS control file.
  • (ASCII) - NLDAS_UMDpredomveg.asc
    This ASCII file lists the frequency with which each of the 14 UMD vegetation types occurs in each of the 1/8th-degree NLDAS grid boxes. The file is formatted as follows:

    Column 1 Grid Column Number
    Column 2 Grid Row Number
    Column 3 Latitude (center of 1/8th-degree grid boxes)
    Column 4 Longitude (center of 1/8th-degree grid boxes)
    Column 5 Total number of 1-km pixels in 1/8th-degree grid box
    Column 6 Frequency of Water (And Goode's Interrupted Space) (Category 0)
    Column 7 Frequency of Evergreen Needleleaf Forest (Category 1)
    Column 8 Frequency of Evergreen Broadleaf Forest (Category 2)
    Column 9 Frequency of Deciduous Needleleaf Forest (Category 3)
    Column 10 Frequency of Deciduous Broadleaf Forest (Category 4)
    Column 11 Frequency of Mixed Cover (Category 5)
    Column 12 Frequency of Woodland (Category 6)
    Column 13 Frequency of Wooded Grassland (Category 7)
    Column 14 Frequency of Closed Shrubland (Category 8)
    Column 15 Frequency of Open Shrubland (Category 9)
    Column 16 Frequency of Grassland (Category 10)
    Column 17 Frequency of Cropland (Category 11)
    Column 18 Frequency of Bare Ground (Category 12)
    Column 19 Frequency of Urban and Built-Up (Category 13)

All illustrations and datasets presented below are provided for informational purposes only,
and are NOT currently used by the NLDAS project.


NLDAS UMD Illustrations (With Fractional Vegetation Adjustment)

Categories 0-3
Adjusted UMD Vegetation Fractional Coverages (Categories 0-3) (JPEG, 108kb)

Categories 4-7
Adjusted UMD Vegetation Fractional Coverages (Categories 4-7) (JPEG, 140kb)

Categories 8-11
Adjusted UMD Vegetation Fractional Coverages (Categories 8-11) (JPEG, 132kb)

Categories 12-13
Adjusted UMD Vegetation Fractional Coverages (Categories 12-13) (JPEG, kb)

Adjusted UMD Land/Water Mask
Adjusted UMD Land/Water Mask (JPEG, 56kb)

Adjusted UMD Predominant Vegetation Types
Adjusted UMD Predominant Vegetation Types (JPEG, 224kb)

NLDAS UMD Datasets (With Fractional Vegetation Adjustment)

  • (Binary) - NLDAS_UMDpredomadjustveg.bin
    This file contains the adjusted predominant UMD vegetation type in binary format. You may find NLDAS_UMDpredomadjustveg.F90 helpful to read the file, as well as a NLDAS_UMDpredomadjustveg.ctl GrADS control file.
  • (ASCII) - NLDAS_UMDpredomadjustveg.asc
    This ASCII file lists the frequency with which each of the 14 adjusted UMD vegetation types occurs in each of the 1/8th-degree NLDAS grid boxes. The file is formatted as follows:

    Column 1 Grid Column Number
    Column 2 Grid Row Number
    Column 3 Latitude (center of 1/8th-degree grid boxes)
    Column 4 Longitude (center of 1/8th-degree grid boxes)
    Column 5 Total number of 1-km pixels in 1/8th-degree grid box
    Column 6 Vegetation Fraction
    Column 7 Frequency of Water (And Goode's Interrupted Space) (Category 0)
    Column 8 Frequency of Evergreen Needleleaf Forest(Category 1)
    Column 9 Frequency of Evergreen Broadleaf Forest (Category 2)
    Column 10 Frequency of Deciduous Needleleaf Forest (Category 3)
    Column 11 Frequency of Deciduous Broadleaf Forest (Category 4)
    Column 12 Frequency of Mixed Cover (Category 5)
    Column 13 Frequency of Woodland (Category 6)
    Column 14 Frequency of Wooded Grassland (Category 7)
    Column 15 Frequency of Closed Shrubland (Category 8)
    Column 16 Frequency of Open Shrubland (Category 9)
    Column 17 Frequency of Grassland (Category 10)
    Column 18 Frequency of Cropland (Category 11)
    Column 19 Frequency of Bare Ground (Category 12)
    Column 20 Frequency of Urban and Built-Up (Category 13)

NLDAS IGBP Illustrations

Categories 1-4
IGBP Vegetation Fractional Coverages (Categories 1-4) (JPEG, 112kb)

Categories 5-8
IGBP Vegetation Fractional Coverages (Categories 5-8) (JPEG, 136kb)

Categories 9-12
IGBP Vegetation Fractional Coverages (Categories 9-12) (JPEG, 128kb)

Categories 13-16
IGBP Vegetation Fractional Coverages (Categories 13-16) (JPEG, 124kb)

Category 17
IGBP Vegetation Fractional Coverages (Category 17) (JPEG, 52kb)

IGBP Land/Water Mask
IGBP Land/Water Mask (JPEG, 60kb)

Predominant Vegetation Types
NLDAS IGBP Predominant Vegetation Types (JPEG, 200kb)

NLDAS IGBP Datasets

  • (Binary) - NLDAS_IGBPpredomveg.bin
    This file contains the predominant IGBP vegetation type in binary format. You may find NLDAS_IGBPpredomveg.F90 helpful to read the file, as well as a NLDAS_IGBPpredomveg.ctl GrADS control file.
  • (ASCII) - NLDAS_IGBPpredomveg.asc
    This ASCII file lists the frequency with which each of the 17 IGBP vegetation types occurs in each of the 1/8th-degree NLDAS grid boxes. The file is formatted as follows:

    Column 1 Grid Column Number
    Column 2 Grid Row Number
    Column 3 Latitude (center of 1/8th-degree grid boxes)
    Column 4 Longitude (center of 1/8th-degree grid boxes)
    Column 5 Total number of 1-km pixels in 1/8th-degree grid box
    Column 6 Frequency of Evergreen Needleleaf Forest (Category 1)
    Column 7 Frequency of Evergreen Broadleaf Forest (Category 2)
    Column 8 Frequency of Deciduous Needleleaf Forest (Category 3)
    Column 9 Frequency of Deciduous Broadleaf Forest (Category 4)
    Column 10 Frequency of Mixed Forest (Category 5)
    Column 11 Frequency of Closed Shrublands (Category 6)
    Column 12 Frequency of Open Shrublands (Category 7)
    Column 13 Frequency of Woody Savannah (Category 8)
    Column 14 Frequency of Savannahs (Category 9)
    Column 15 Frequency of Grasslands (Category 10)
    Column 16 Frequency of Permanent Wetlands (Category 11)
    Column 17 Frequency of Croplands (Category 12)
    Column 18 Frequency of Urban and Built-Up (Category 13)
    Column 19 Frequency of Cropland / Natural Vegetation Mosaic (Category 14)
    Column 20 Frequency of Snow and Ice (Category 15)
    Column 21 Frequency of Barren or Sparsely Vegetated (Category 16)
    Column 22 Frequency of Water Bodies (Category 17)

NLDAS IGBP Illustrations (With Fractional Vegetation Adjustment)

Categories 1-4
Adjusted IGBP Vegetation Fractional Coverages (Categories 1-4) (JPEG, 108kb)

Categories 5-8
Adjusted IGBP Vegetation Fractional Coverages (Categories 5-8) (JPEG, 128kb)

Categories 9-12
Adjusted IGBP Vegetation Fractional Coverages (Categories 9-12) (JPEG, 124kb)

Categories 13-16
Adjusted IGBP Vegetation Fractional Coverages (Categories 13-16) (JPEG, 128kb)

Category 17
Adjusted IGBP Vegetation Fractional Coverages (Category 17) (JPEG, 52kb)

IGBP Land/Water Mask
Adjusted IGBP Land/Water Mask (JPEG, 56kb)

Predominant Vegetation Types
Adjusted NLDAS IGBP Predominant Vegetation Types (JPEG, 204kb)

NLDAS IGBP Datasets (With Fractional Vegetation Adjustment)

  • (Binary) - NLDAS_IGBPpredomadjustveg.bin
    This file contains the adjusted predominant IGBP vegetation type in binary format. You may find NLDAS_IGBPpredomadjustveg.F90 helpful to read the file, as well as a NLDAS_IGBPpredomadjustveg.ctl GrADS control file.
  • (ASCII) - NLDAS_IGBPpredomadjustveg.asc
    This ASCII file lists the frequency with which each of the 17 adjusted IGBP vegetation types occurs in each of the 1/8th-degree NLDAS grid boxes. The file is formatted as follows:

    Column 1 Grid Column Number
    Column 2 Grid Row Number
    Column 3 Latitude (center of 1/8th-degree grid boxes)
    Column 4 Longitude (center of 1/8th-degree grid boxes)
    Column 5 Total number of 1-km pixels in 1/8th-degree grid box
    Column 6 Vegetation Fraction
    Column 7 Frequency of Evergreen Needleleaf Forest (Category 1)
    Column 8 Frequency of Evergreen Broadleaf Forest (Category 2)
    Column 9 Frequency of Deciduous Needleleaf Forest (Category 3)
    Column 10 Frequency of Deciduous Broadleaf Forest (Category 4)
    Column 11 Frequency of Mixed Forest (Category 5)
    Column 12 Frequency of Closed Shrublands (Category 6)
    Column 13 Frequency of Open Shrublands (Category 7)
    Column 14 Frequency of Woody Savannah (Category 8)
    Column 15 Frequency of Savannahs (Category 9)
    Column 16 Frequency of Grasslands (Category 10)
    Column 17 Frequency of Permanent Wetlands (Category 11)
    Column 18 Frequency of Croplands (Category 12)
    Column 19 Frequency of Urban and Built-Up (Category 13)
    Column 20 Frequency of Cropland / Natural Vegetation Mosaic (Category 14)
    Column 21 Frequency of Snow and Ice (Category 15)
    Column 22 Frequency of Barren or Sparsely Vegetated (Category 16)
    Column 23 Frequency of Water Bodies (Category 17)