AUTHORS: Jesslyn Brown; Charles Robison; Jon Dewitz; Heather Tollerud; Suming Jin; Rylie Fleckenstein; Chris Barber; George Xian; Josephine Horton; Congcong Li; Danny Howard
ABSTRACT: Land cover is a high priority data theme within the U.S. federal government and is foundational for many applications. These data are often combined with other data sources to provide a robust structure for scientific study and to inform decisions by managers and the public. The U.S. Geological Survey (USGS) is building a capability for an integrated annual land cover and land cover change framework using cloud computing. To provide the most relevant land cover and land cover change information for the United States, mapped land cover (and derived products) should involve regular production, updating and improvement based on robust research, and validation of land cover and land cover change. USGS has recently released an annual record of land cover and fractional impervious surface for the conterminous U.S. (CONUS) called Annual National Land Cover Database (NLCD) spanning a thirty-nine-year period from 1985 to 2023. The NLCD has characterized land cover and land cover change nation-wide paving the way for Annual NLCD. Utilizing the Landsat observations, legacy NLCD has produced land cover and other data themes at 30-meter spatial resolution. In earlier releases, NLCD released map products for CONUS across nine epochs from 2001 to 2021 (2001, 2004, 2006, 2008, 2011, 2013, 2016, 2019, and 2021), producing maps describing characteristics of the land surface such as thematic class (e.g., developed, cultivated crops, and forest), percent impervious surface, and percent tree canopy cover. Annual NLCD employs a new methodology, operating in the cloud, based on the long Landsat satellite record, various chained deep learning models, harmonic time series analysis, and several post-classification procedures producing land cover through time. The database will have higher frequency and lower latency and will inform users of land change dynamics, including forest regrowth after harvest or wildfire, climatologically driven water cycles, and land use management patterns such as urban growth. An update is expected in 2025. Products for other regions (Alaska and Hawaii) are planned in 2026.
