GLDAS currently uses the land surface datasets from the Moderate Resolution Imaging Spectroradiometer (MODIS) as our "standard". The GLDAS version 2 products (GLDAS2) use the data described on this page. Previously, GLDAS has used the Advanced Very High Resolution Radiometer (AVHRR) based datasets, in which we refer to our "old standard". The old standard vegetation parameter datasets are used in GLDAS version 1 products (GLDAS1) and are available at the bottom of this page.
GLDAS Land/Sea Mask Dataset
GLDAS adopted the MOD44W MODIS Water Mask as the standard land/sea mask. The mask data [Carroll et al, 2009] is produced at University of Maryland and described here. Instead of deriving the mask from a land cover data as done in GLDAS1, the standard mask is "imposed" to land cover data and other surface parameter maps in GLDAS2. In order to create the land/sea masks on this page, the percent coverage of 0.01 degree water pixels in each GLDAS grid box was used such that grid boxes made up of more than 50% water were assigned a "water" value of 0 in the GLDAS land/sea mask, while all other grid boxes received a "land" value of 1.
GLDAS standard Land/Sea Mask
- GLDAS standard Land/Sea Mask Data (NetCDF): 0.25 degree, 1 degree
- GLDAS standard Land/Sea Mask Data in other format (zip file including big_endian Binary format, Fortran code to read in, GrADS control file, and Ascii format data in 0.25 degree): 0.25 degree, 1 degree
GLDAS Land Cover Dataset
GLDAS runs its 1-D land surface models on vegetation-based tiles to simulate variability below the scale of the model grid squares. A tile is not tied to a specific location within the grid square. Instead, each tile represents the area covered by a given vegetation type. The maximum number of tiles per grid square is determined by the user. A high resolution MODIS land cover dataset is the basis for designating tile space. In GLDAS2, different land cover classification schemes are used depending on the land surface model.
The land cover in GLDAS2/Noah version 3.3 is based on a 30 arc second MODIS vegetation data that uses modified IGBP classification scheme (see details). The predominant vegetation type in each 1/4 grid square is shown below.
|1||Evergreen Needleleaf Forest|
|2||Evergreen Broadleaf Forest|
|3||Deciduous Needleleaf Forest|
|4||Deciduous Broadleaf Forest|
|13||Urban and Built-Up|
|14||Cropland/Natural Vegetation Mosaic|
|15||Snow and Ice|
|16||Barren or Sparsely Vegetated|
|20||Bare Ground Tundra|
- GLDAS Dominant Vegetation Type Data (NetCDF): 0.25 degree, 1 degree
- GLDAS Dominant Vegetation Type Data in other format (zip file including big_endian Binary data, Fortran code to read in, GrADS control file, and ASCII data at 0.25 degree): 0.25 degree, 1 degree