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ISLSCP II FASIR-adjusted NDVI Biophysical Parameter Fields, 1982-1998
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Revision date: March 31, 2010


The Fourier-Adjusted, Sensor and Solar zenith angle corrected, Interpolated, Reconstructed (FASIR) adjusted Normalized Difference Vegetation Index (NDVI) data set and derived biophysical parameter fields were generated to provide a 17-year, satellite record of monthly changes in the photosynthetic activity of terrestrial vegetation. This multiple resolution (1/4, 1/2 and 1 degree in latitude and longitude) biophysical parameter data set contains essential variables for the calculation of photosynthesis, and the energy and water exchange between the Earth's surface (in particular of vegetation) and the lower boundary layer of the atmosphere. The Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) is related to the light absorption and the photosynthetic capacity of vegetation. It also serves as an intermediate variable to calculate vegetation cover fraction (Vcover), total Leaf Area Index (LAI_T), green leaf area index (LAI_G), roughness length (z0), zero plane displacement (d), and snow-free albedo. The biophysical parameters were derived assuming one canopy layer. The production of the FASIR NDVI data set and its associated biophysical parameters was funded by NASA's Land Surface Hydrology program and the Higher Education Funding Council for Wales (HEFCW) as a core component of the International Satellite Land Surface Climatology Project (ISLSCP) Initiative II Data Collection.

Additional Documentation:

This data set is one of the products of the International Satellite Land-Surface Climatology Project, Initiative II (ISLSCP II) data collection, which contains 50 global time series data sets for the ten-year period 1986 to 1995. A complete description of the data, their derivation, acknowledgements, and references provided by the ISLSCP II Data Management Staff is included with this data set as a companion file named 1_fasir_biophys_doc.pdf.

ISLSCP II is a consistent collection of data sets that were compiled from existing data sources and algorithms, and were designed to satisfy the needs of modelers and investigators of the global carbon, water and energy cycle. The data were acquired from a number of U.S. and international agencies, universities, and institutions. The data and documentation have undergone two peer reviews.

ISLSCP is one of several projects of Global Energy and Water Cycle Experiment (GEWEX) [] and has the lead role in addressing land-atmosphere interactions -- process modeling, data retrieval algorithms, field experiment design and execution, and the development of global data sets.

Related Data Sets

ISLSCP II GIMMS Monthly NDVI, 1981-2002

ISLSCP II FASIR-adjusted NDVI, 1982-1998

ISLSCP II Leaf Area Index (LAI) from Field Measurements, 1932-2000

Data Citation:

Cite this data set as follows:

Sietse, O.L. 2010. ISLSCP II FASIR-adjusted NDVI Biophysical Parameter Fields, 1982-1998. In Hall, Forrest G., G. Collatz, B. Meeson, S. Los, E. Brown de Colstoun, and D. Landis (eds.). ISLSCP Initiative II Collection. Data set. Available on-line [] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/970

File Information:

The archived data sets for ISLSCP II have been organized by categories. This data set is in the vegetation category--a collection of vegetation and albedo data sets.

Data Set Spatial Extent: Global gridded

Westernmost Longitude: -180 W

Easternmost Longitude: 180 E

Northernmost Latitude: 90 N

Southernmost Latitude: -90 S

Projection: Geographic

Data Set Spatial Resolution: one, half, and quarter degree in both latitude and longitude

Data Set Temporal Extent: January 1982-December 1998

Data File Format

All of the data files in each data set within the ISLSCP Initiative II data collection are in ESRI ASCII GRID format for ArcInfo. The file format consists of numerical fields of varying length, which are delimited by a single space and arranged in columns and rows.

There are 16  data files which have been combined according to spatial resolution: one degree, half degree, and quarter degree respectively: 15 files are named according to the biophysical field descriptors. See the examples below.  There is also 1 data file which contains the vegetation cover for the entire period from 1982 to 1998:

Biophysical field descriptors used in file names
Field Description
fapar Fraction of photosynthetically active radiation absorbed by the green fraction of the vegetation canopy
tlai Total leaf area index
glai Green leaf area index
rough  Aerodynamic roughness length (z0)
0plane Zero plane displacement (d) 

The individual files contained in the .zip files are named based on the month and year of the data.

        Example: fasir_fapar413_1d_199009.asc is the 1-degree FAPAR from September 1990.

Data file naming conventions are described in the 0_fasir_biophys_readme.txt 

Data Access:

These data are available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC)  [].

Data Archive Contact Information:

Telephone: +1 (865) 241-3952