Vancouver Island 1m DEMs have some big holes
The Canadian HRDEM dataset is made up of a number of different projects, each consisting of 1m or 2m lidar DEMs of different parts of Canada.
The project covering parts of Vancouver Island, named Vancouver_Island_Sunshine_Coast_2018, has a few rasters with corrupt data. Typically this is manifested in blocky areas with very low elevation, though there are a few areas with very high elevation.
Visualising the data, the corrupt areas are very clear. Here’s a heatmap of dtm_1m_utm10_w_5_136:
Looking at a hillshaded render, it seems there is some realistic texturing inside the corrupt region, but with both an incorrect vertical shift and diagonal striped artefacts:
These are the files with potential corruption:
dtm_1m_utm10_w_10_137.tif dtm_1m_utm10_w_10_138.tif dtm_1m_utm10_w_10_146.tif dtm_1m_utm10_w_11_137.tif dtm_1m_utm10_w_11_138.tif dtm_1m_utm10_w_11_140.tif dtm_1m_utm10_w_11_141.tif dtm_1m_utm10_w_11_147.tif dtm_1m_utm10_w_11_152.tif dtm_1m_utm10_w_11_153.tif dtm_1m_utm10_w_12_138.tif dtm_1m_utm10_w_12_140.tif dtm_1m_utm10_w_12_148.tif dtm_1m_utm10_w_12_149.tif dtm_1m_utm10_w_13_138.tif dtm_1m_utm10_w_13_139.tif dtm_1m_utm10_w_13_149.tif dtm_1m_utm10_w_13_150.tif dtm_1m_utm10_w_14_139.tif dtm_1m_utm10_w_14_140.tif dtm_1m_utm10_w_14_141.tif dtm_1m_utm10_w_15_139.tif dtm_1m_utm10_w_15_144.tif dtm_1m_utm10_w_15_154.tif dtm_1m_utm10_w_16_140.tif dtm_1m_utm10_w_16_142.tif dtm_1m_utm10_w_16_144.tif dtm_1m_utm10_w_16_153.tif dtm_1m_utm10_w_17_143.tif dtm_1m_utm10_w_17_157.tif dtm_1m_utm10_w_18_157.tif dtm_1m_utm10_w_19_142.tif dtm_1m_utm10_w_19_157.tif dtm_1m_utm10_w_19_158.tif dtm_1m_utm10_w_1_150.tif dtm_1m_utm10_w_20_158.tif dtm_1m_utm10_w_21_146.tif dtm_1m_utm10_w_21_158.tif dtm_1m_utm10_w_22_147.tif dtm_1m_utm10_w_24_148.tif dtm_1m_utm10_w_26_160.tif dtm_1m_utm10_w_28_157.tif dtm_1m_utm10_w_2_141.tif dtm_1m_utm10_w_2_146.tif dtm_1m_utm10_w_3_136.tif dtm_1m_utm10_w_4_136.tif dtm_1m_utm10_w_4_139.tif dtm_1m_utm10_w_5_136.tif dtm_1m_utm10_w_5_148.tif dtm_1m_utm10_w_6_151.tif dtm_1m_utm10_w_7_136.tif dtm_1m_utm10_w_7_150.tif dtm_1m_utm10_w_7_151.tif dtm_1m_utm10_w_8_136.tif dtm_1m_utm10_w_8_145.tif dtm_1m_utm10_w_9_137.tif dtm_1m_utm10_w_9_145.tif dtm_1m_utm10_w_9_146.tif dtm_1m_utm9_e_10_158.tif dtm_1m_utm9_e_10_161.tif dtm_1m_utm9_e_10_162.tif dtm_1m_utm9_e_11_161.tif dtm_1m_utm9_e_11_162.tif dtm_1m_utm9_e_13_160.tif dtm_1m_utm9_e_14_157.tif dtm_1m_utm9_e_16_159.tif dtm_1m_utm9_e_19_148.tif dtm_1m_utm9_e_21_146.tif dtm_1m_utm9_e_21_147.tif dtm_1m_utm9_e_21_158.tif dtm_1m_utm9_e_22_158.tif dtm_1m_utm9_e_23_157.tif dtm_1m_utm9_e_23_158.tif dtm_1m_utm9_e_24_142.tif dtm_1m_utm9_e_25_158.tif dtm_1m_utm9_e_26_143.tif dtm_1m_utm9_e_26_153.tif dtm_1m_utm9_e_27_145.tif dtm_1m_utm9_e_27_154.tif dtm_1m_utm9_e_28_141.tif dtm_1m_utm9_e_28_145.tif dtm_1m_utm9_e_29_140.tif dtm_1m_utm9_e_29_141.tif dtm_1m_utm9_e_4_161.tif dtm_1m_utm9_e_5_160.tif dtm_1m_utm9_e_5_161.tif dtm_1m_utm9_e_6_159.tif dtm_1m_utm9_e_7_158.tif dtm_1m_utm9_e_7_160.tif dtm_1m_utm9_e_7_161.tif dtm_1m_utm9_e_7_163.tif dtm_1m_utm9_e_8_160.tif dtm_1m_utm9_e_9_160.tif dtm_1m_utm9_e_9_162.tif dtm_1m_utm9_e_9_163.tif
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