DEM
DEM
Hi. I downloaded some tiff digital elevation models. But then I noticed that the height values were from 0 to 2. The images show mountains and valleys, could the values be in kilometers, or some other unit?
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LP DAAC - dgolon
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Re: DEM
Hi @slozanot which DEM data product(s) are you trying to use?
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ASF - hjkristenson
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Re: DEM
Hi @slozanot,
The DEM file included in the ALOS PALSAR RTC product package is a copy of the DEM used to perform the radiometric terrain correction. The values are in meters, but the values will differ from the original DEM used, as an ellipsoid correction is applied before it can be used for RTC. These files are not intended to be used in place of a standard DEM product, but are included to assist in interpreting/evaluating the RTC products.
The source DEMs used for this project vary depending on the location of the granule. Details about the DEMs used and the adjustments applied are available here:
https://asf.alaska.edu/information/palsar-rtc-dem-information/
Note that the DEM file is resampled to match the pixel spacing of the RTC product, so the pixel spacing does not necessarily reflect the resolution of the source DEM.
General information about the ALOS PALSAR RTC products is available here:
https://asf.alaska.edu/data-sets/derived-data-sets/alos-palsar-rtc/alos-palsar-radiometric-terrain-correction/
The DEM file included in the ALOS PALSAR RTC product package is a copy of the DEM used to perform the radiometric terrain correction. The values are in meters, but the values will differ from the original DEM used, as an ellipsoid correction is applied before it can be used for RTC. These files are not intended to be used in place of a standard DEM product, but are included to assist in interpreting/evaluating the RTC products.
The source DEMs used for this project vary depending on the location of the granule. Details about the DEMs used and the adjustments applied are available here:
https://asf.alaska.edu/information/palsar-rtc-dem-information/
Note that the DEM file is resampled to match the pixel spacing of the RTC product, so the pixel spacing does not necessarily reflect the resolution of the source DEM.
General information about the ALOS PALSAR RTC products is available here:
https://asf.alaska.edu/data-sets/derived-data-sets/alos-palsar-rtc/alos-palsar-radiometric-terrain-correction/