Pixel-wise elevation differences with a spatial resolution of 2m, derived from ArctciDEM by: "the most recent elevation - the oldest elevation". grid_ids_DEM_diff_grid42147.tif: the elevation differences. The pixel value/ 100.0 is the difference (unit: meters). grid_ids_date_diff_grid42147.tif: pixel-wise differences of acquisition dates between the most recent elevation and the oldest elevation. grid_ids_date_diff_grid42147.txt: the indices and ArcticDEM files for producing the elevation differences, we can tell the acquisition dates from the file names. grid_ids_date_diff_grid42147_newIndex.tif: the index of the most recent ArcticDEM file at each pixel (grid_ids_date_diff_grid42147.txt). grid_ids_date_diff_grid42147_oldIndex.tif: the index of the oldest ArcticDEM file at each pixel (grid_ids_date_diff_grid42147.txt).