The ASTER Surface Reflectance VNIR and SWIR (AST_07) data product contains measures of the fraction of incoming solar radiation reflected from the Earth’s surface to the ASTER instrument corrected for atmospheric effects and viewing geometry for both the Visible and Near Infrared (VNIR) and Shortwave Infrared (SWIR) sensors. Each product delivery includes two Hierarchical Data Format - Earth Observing System (HDF-EOS) files: one for the VNIR, and the other for the SWIR. They are distinguished from one another by a one-second difference in the production time that appears as part of the file name.
|File Size||~124 MB|
|Temporal Extent||2000-03-06 to Present|
|Coordinate System||Universal Transverse Mercator (UTM)|
|Datum||World Geodetic System (WGS84)|
|File Format||HDF-EOS or GeoTIFF|
|Geographic Dimensions||~60 km x 60 km|
|Number of Science Dataset (SDS) Layers||9|
|Columns/Rows||4200 x 4980 (VNIR) and 2100 x 2490 (SWIR)|
|Pixel Size||15 m (VNIR) and 30 m (SWIR)|
|SDS Name||Description||Units||Data Type||Fill Value||No Data Value||Valid Range||Scale Factor|
|VNIR_Band1||15 meter resolution VNIR Band 1 (0.52 to 0.60 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||VNIR_Band2||15 meter resolution VNIR Band 2 (0.63 to 0.69 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||VNIR_Band3N||15 meter resolution VNIR Band 3 (0.78 to 0.86 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band4||30 meter resolution SWIR Band 4 (1.600 to 1.700 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band5||30 meter resolution SWIR Band 5 (2.145 to 2.185 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band6||30 meter resolution SWIR Band 6 (2.185 to 2.225 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band7||30 meter resolution SWIR Band 7 (2.235 to 2.285 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band8||30 meter resolution SWIR Band 8 (2.295 to 2.365 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001||SWIR_Band9||30 meter resolution SWIR Band 9 (2.360 to 2.430 µm)||N/A||16-bit signed integer||N/A||N/A||0 to 1000||0.001|
There are three groups of ancillary data inputs used in the atmospheric correction of ASTER radiance and reflectance:
Users are advised that ASTER SWIR data acquired from April 2008 to the present exhibit anomalous saturation of values and anomalous striping. This effect is also present for some prior acquisition periods. Please refer to the ASTER SWIR User Advisory Document for more details.