UM Geospatial Digital Special Collections

Citation: Multi-Resolution Land Characteristics Consortium (2023). NLCD 2021 Land Cover (CONUS) [gis dataset]. Multi-Resolution Land Characteristics Consortium, U.S. Geological Survey, Sioux Falls, SD. https://doi.org/10.5066/P9JZ7AO3. last updated: 2024-10-28 (update frequency: Never). Abstract: The U.S. Geological Survey (USGS), in partnership with several federal agencies, has now developed and released seven National Land Cover Database (NLCD) products: NLCD 1992, 2001, 2006, 2011, 2016, 2019, and 2021. Beginning with the 2016 release, land cover products were created for two-to-three-year intervals between 2001 and the most recent year. These products provide spatially explicit and reliable information on the Nation’s land cover and land cover change. NLCD continues to provide innovative, consistent, and robust methodologies for production of a multi-temporal land cover and land cover change database. NLCD 2021 adds an additional year to the map products produced for NLCD 2019, with a streamlined compositing process for assembling and preprocessing Landsat imagery and geospatial ancillary datasets; a temporally, spectrally, and spatially integrated land cover change analysis strategy; a theme-based post-classification protocol for generating land cover and change products; a continuous fields biophysical parameters modeling method; and a scripted operational system. The overall accuracy of the 2019 Level I land cover was 91%. Results from this study confirm the robustness of this comprehensive and highly automated procedure for NLCD 2021 operational mapping (see https://doi.org/10.1080/15481603.2023.2181143 for the latest accuracy assessment publication). Questions about the NLCD 2021 land cover product can be directed to the NLCD 2021 land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov. See included spatial metadata for more details. Key words: land cover, Landsat, Sentinel-2, CONUS, United States Open Geospatial Consortium Standards: | WMS (coming soon) | WFS (coming soon) Analytical Functions: gdsc_zonal_statistics(table=us_2021_nlcd_land_cover,lat=25.718,lng=-80.279,radius=500) ETL documentation

ETL for us_2021_nlcd_land_cover

######### # GDSC ETL is performed in two steps: shell script to ETL data into postgres # and then additional transformations with SQL in postGIS (if needed). #### ######### # Step 1 - bash script (pseudo code) #### # create directory structure and move into it mkdir -p /data/us_2021_nlcd_land_cover/{download,etl} && cd /data/us_2021_nlcd_land_cover # set update flag based on last update and update frequency do_update=0 if date() < last_update + update_frequency else do_update = 1 # download if update flag is set: if do_update == 1 then wget -O download/us_2021_nlcd_land_cover.zip 'https://s3-us-west-2.amazonaws.com/mrlc/nlcd_2021_land_cover_l48_20230630.zip' # unzip to download directory if update flag is set if do_update == 1 then unzip -d download download/us_2021_nlcd_land_cover.zip && rm download/us_2021_nlcd_land_cover.zip