G-LiHT Hyperspectral Radiance image, acquired over Bowie, Maryland in June, 2012.View full-size image
Goddard’s LiDAR, Hyperspectral, and Thermal Imager (G-LiHT) mission is a portable, airborne imaging system that aims to simultaneously map the composition, structure, and function of terrestrial ecosystems. G-LiHT primarily focuses on a broad diversity of forest communities and ecoregions in North America, mapping aerial swaths over the conterminous United States (CONUS), Alaska, Puerto Rico, and Mexico.
The purpose of G-LiHT’s Hyperspectral Radiance data product (GLRADS) is to provide high-resolution radiance data, ranging in wavelength from 418 to 920 nanometers across 114 spectral bands. Radiance data is computed as the ratio between observed upwelling radiance and downwelling hemispheric irradiance, then corrected for differences in cross-track illumination and Bidirectional Reflectance Distribution Function (BRDF) using an empirically derived multiplier. At a nominal flying height of 335 m above ground level (AGL), the at-sensor radiance is a close approximation of surface radiance.
GLRADS data are processed as a zipped raster data product (GeoTIFF) with associated header file (.hdr) at 1 meter spatial resolution over locally defined areas. A low-resolution browse is also provided with a color map applied in PNG format.
|File Size||>1 GB|
|Temporal Extent||2011-06-30 to Present|
|Spatial Extent||North America|
|Coordinate System||Universal Transverse Mercator (UTM)|
|Datum||World Geodetic System (WGS84)|
|Number of Science Dataset (SDS) Layers||1|
|Pixel Size||1 m|
|SDS Name||Description||Units||Data Type||Fill Value||No Data Value||Valid Range||Scale Factor|
|Band 1-114||Radiance||N/A||32-bit floating point||N/A||N/A||0 to 10000||0.0001|
Information on the GLRADS product can be found on the G-LiHT website.