Table of Contents
Dataset Papers in Science
Volume 2015 (2015), Article ID 564279, 11 pages
Dataset Paper

Mapping Biophysical Parameters for Land Surface Modeling over the Continental US Using MODIS and Landsat

1Biospheric Sciences Laboratory, NASA’s Goddard Space Flight Center, Greenbelt, MD 20771, USA
2Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20742, USA
3Center for Research and Applications in Remote Sensing (CARTEL), Sherbrooke University, Sherbrooke, QC, Canada J1K 2R1
4Joint Global Change Research Institute, Pacific Northwest National Laboratory and the University of Maryland, College Park, MD 20740, USA
5Terrestrial Information Systems Laboratory, NASA’s Goddard Space Flight Center, Greenbelt, MD 20771, USA

Received 8 October 2014; Revised 12 January 2015; Accepted 12 January 2015

Academic Editor: Jai Vaze

This dataset has been dedicated to the public domain using the CC0 waiver.



Dataset Item 1 (Binary Data). It shows 13 different land cover classes, classes 0 to 12 (Table 1 and Figure 3). Each class contains two files representing the land cover type (LC<type> and the land cover type fraction (LC<type>, where “<type>” is the land cover type (0 to 12), and 46 files, for each of the time periods, labeled “biophys<period>,” namely, biophys1 to biophys46, where <period> is the 8-day time period varying from 1 to 46, each containing 7 biophysical parameters for that land cover class. For example, to obtain the biophysical parameters for the Deciduous Broadleaf class (LC2) for the 18th time period in 2001, access the LC2_biophys18 file. As an example, Table 4 illustrates the land cover class, the fraction (%), and the LAI (m2·m−2) of all 10 classes coexisting in the CMG defined by (row = 208, column = 992) for period 18. To determine the latitude and longitude from the row/column of a point, one can use the following relationship: Latitude = NL − (row-1) gridsize and Longitude = WL + (column-1) gridsize, where the NL is the northernmost latitude (49.475°), WL is the westernmost longitude (125.025°), and the gridsize is equal to 0.05°. Using these calculations, the point (row = 208, ) should be at latitude 39.125° north and longitude 75.475° west.For each class, the LC<type> file shows the code of that particular cover type in the CMG (Table 1) wherever the class exists with a fraction greater than 1% and fill value (−999.0) elsewhere. The threshold fraction of 1% is chosen to build the land cover types and is supposed to represent the error in classification emanating from the MCD12Q1. Users are encouraged to choose their own threshold fraction to build land cover type masks based on the land cover fractions. The LC<type> file contains the coregistered fraction of the particular land cover type for all pixels (Figure 4). Each data file contains 1160 columns and 490 rows. The land cover types and fractions are floating point values from 0 to 12 for the types and from 0 to 100% for the fractions. Though we have included “tundra” as a land cover class, there is no tundra recorded in the contiguous US and its land cover fraction is not provided. For portability and general access, the format storing data using the American Standard Code for Information Interchange (ASCII) is provided for scientists who prefer to write their own code to manipulate the information. Data files are 2-dimensional array with the longitude varying from west (125.025 W) to east (67.075 W) and then the latitude varying from north (49.475 N) to south (25.025 N) with an equal grid spacing of 0.05 degrees. The biophysical parameters are written in 46 data files corresponding to 46 8-day periods over which MODIS data have been composited with period 1 corresponding to day 1 to day 8 of the calendar year and period 2 corresponding to day 9 to day 16, and so on. Each file contains seven biophysical parameters for that 8-day period written as seven appended layers in the order shown in Table 2. Similar to the land cover types and fractions, the biophysical parameters are also written in ASCII format. The biophysical data files are presented as a 3-dimensional array with the longitude varying first, then the latitude, and then the biophysical parameters changing in the sequence shown in Table 2. Note that biophysical parameters are not defined over inland water (class 0) and tundra (class 10). Figure 5 shows an example of the temporal profile of the seven biophysical parameters associated with cropland in one grid cell.

Dataset Item 2 (Source Code). A simple code (test_read_biophysical_ascii.f) written in standard FORTRAN is also included with the dataset to help read the provided ASCII data files.

Dataset Item 3 (Binary Data). For portability and general access, we also provided the same dataset in binary form which is readable by some remote sensing and geographical information systems (GIS) software such as ENVI and Arcgis. For example, users can use the parameters listed in Table 5 to read the data within this item in ENVI.

Dataset Item 4 (Source Code). We also provide a simple code (test_read_biophysical_binary.f) written in standard FORTRAN to help read the provided binary data files.