The 7- x 7-km grid containing the field or tower site is provided to enable comparison of pixel values of MODIS products with field data collected at a site. The values are intended to be examined over time either as a collection of individual values or combined (e.g., the average and range) within a 3- x 3-km grid or a 5- x 5-km grid around the site. Examples of analyses using the ASCII subset data can be found in presentations. If users would like to examine the MODIS data spatially in a map, we suggest that they obtain the GeoTIFF subsets or MODIS products from the LP DAAC.

Please note that the grid and pixel sizes are not exact multiples of 1 km, but are only approximations. For instance, the grid and pixel size for the 1 km Sinusoidal grid is approximately 926 m. For additional information, please view the MODIS Web site.

Location of the Field Site / Tower Site: The location of the field study or flux tower sites is in decimal degrees provided by the site investigators. We used that information and the MODIS Tile Mapper to identify the pixel in which the site is located. In the site location information, we indicate which pixel contains the field or tower site.

Site Corner Points: For the 1, 147 sites subsetted for Collection 5, we provide field site and corner coordinates in the data visualization page.

For Collection 5, we provide a table of the coordinates, in latitude/longitude decimal degrees, of the center and corners of the 7-km x 7-km subsets are provided for reference. The corner coordinates represent the outermost corner of the respective pixels, which are identified by compass directions northeast (NE), southeast (SE), southwest (SW) and northwest (NW). In addition, the coordinates of the flux tower or field site are provided along with the pixel in which the field or tower site is located.