Defines which impervious layer pixels are roads and provides the best fit description for impervious pixels that are not roads. Download the NLCD2016 land cover classification legend. (2011) for our analysis. (MRLC) Consortium, a partnership of federal agencies led by the Standard error for the model as a percentage from 0 to 45. rive impervious surface coefficients per NLCD 92 class in por-tions of the Mid-Atlantic physiographic region. The U.S. NLCD impervious surface data set may provide a high-quality nationally consistent land cover data set in a GIS-ready format that can be used to estimate TIA value. bare ground, litter, sagebrush, big sagebrush and annual herbaceous, along The proportion of shrub canopy in each 30m pixel. NLCD also provides unique products not represented in LCMAP data that may be useful for specific user applications. Primary road in urban area : interstates and other major roads. The annual only grass and forb proportion in each in 30m pixel. Tree Canopy- is the layer of stems of trees, leaves, branches that cover the ground when viewed from above. A new product for NLCD 2016 land cover is the NLCD Land Cover Change Index. Download the per pixel estimates of percent imperviousness legend. The proportion of big sagebrush canopy in each 30m pixel. The annual and perennial grass and forb proportion in each 30m pixel. Mixed forest: areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. 30-meter pixel in the Western United States covered by shrub, herbaceous, Remote Sensing of Environment, 114, 1676-1686. Download the per pixel estimates of percent tree canopy legend. Included in NLCD2011, NLCD2011_AK, NLCD2011_HI, and NLCD2011_PR. These areas most commonly include large-lot single-family housing units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion control, or aesthetic purposes. Impervious surfaces account for 80 to100 percent of the total cover. parts of Kenai Peninsula Borough and Anchorage Municipality are available. 1992 data are primarily based on unsupervised classification of Landsat data, while the rest of the images rely on the imperviousness data layer for the ... USGS/NLCD, Percent of the pixel that's covered by tree canopy. Accuracy assessment of NLCD 2006 focused on four primary products: 2001 land cover, 2006 land cover, land-cover change between 2001 and 2006, and impervious surface … while the rest of the images rely on the imperviousness data layer for the Included in images NLCD2001, NLCD2006, NLCD2011, and NLCD2016. Thinned road outside urban area : small tertiary roads that generally are not paved and have been removed from the landcover but remain as part of the impervious surface product. Impervious surfaces account for 50% to 79% of the total cover. These areas most commonly include single-family housing units. Cultivated crops: areas used for the production of annual crops, such as corn, soybeans, vegetables, tobacco, and cotton, and also perennial woody crops such as orchards and vineyards. Additional Generally, vegetation accounts for less than 15% of total cover. Tree cover is only available on a strip along the coast from the southern Source, A New Generation of the United States National Land Cover Database: Requirements, Research Priorities, Design, and Implementation Strategies. Consequently, the actual cell sizes were 1.44 ha (4-x-4 NLCD pixels), 5.76 ha (8-x-8 NLCD pixels), 10.89 ha (11-x-11 NLCD pixels), 32.49 ha (19-x-19 NLCD pixels), 51.84 ha (24-x-24 NLCD pixels), 98.01 ha (33-x-33 NLCD pixels), and 198.81 ha (47-x-47 NLCD pixels). 4. NLCD 2011 percent developed impervious pixels, identified as changed, were extracted to NLCD developed class codes using NLCD 2011 legend thresholds for developed classes and added to the change pixel map. Perennial ice/snow: areas characterized by a perennial cover of ice and/or snow, generally greater than 25% of total cover. (They could not be merged in due to having a different projection from the continental US Population Data (required only for imperviousness coefficient derivation process) Obtaining the Data . NLCD Legend Land Cover Class Descriptions Developed, High Intensity Developed, High Intensity - Includes highly developed areas where people reside or work in high numbers. Impervious Surface– are mainly artificial surface covered by impenetrable materials (asphalt, concrete, etc.) The suite of cell sizes was … Emergent herbaceous wetlands: areas where perennial herbaceous vegetation accounts for greater than 80% of vegetative cover and the soil or substrate is periodically saturated with or covered with water. Tertiary road in urban area : any two-lane road. Lichens: Alaska only areas dominated by fruticose or foliose lichens generally greater than 80% of total vegetation. These areas most commonly include large-lot single-family housing units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion control, or aesthetic purposes. Impervious surfaces account for 20-49 percent of total cover. These areas are not subject to intensive management such as tilling, but can be utilized for grazing. For the impervious layer, only the These areas most commonly include single-family housing units. National Land Cover Dataset: Impervious Surface 2001 The National Land Cover Dataset (NLCD) Impervious Surface 2001 is a raster impervious cover map developed by the U.S. Geological Survey (USGS) for the conterminous United States, southeast Alaska, Hawaii, and Puerto Rico at a spatial resolution of 30 meters. NLCD 2006 percent developed impervious pixels, identified as changed, were extracted to NLCD developed class codes using NLCD 2001 legend thresholds for developed classes and added to the change pixel map. NLCD (the National Land Cover Database) is a 30-m Landsat-based land cover database spanning 8 epochs (1992, 2001, 2004, 2006, 2008, 2011, 2013 and 2016). Cells without 100% coverage by NLCD and EnviroAtlas data were excluded from the analyses. (Note: These coefficients will be derived as an example in the Tutorial and the process can be repeated for other areas.) Yang, L., Jin, S., Danielson, P., Homer, C., Gass, L., Case, A., Costello, C., Dewitz, J., Fry, J., Funk, M., Grannemann, B., Rigge, M. and G. Xian. Included in images NLCD2011, NLCD2011_AK, NLCD2011_HI, NLCD2011_PR, and NLCD2016. USA NLCD Impervious Surface USA NLCD Land Cover 2006 USA NLCD Land Cover 2011 USA NLCD Land Cover Change. NLCD classes. Included in NLCD2016. image is not directly comparable to any later editions of NLCD. The change index was designed to assist NLCD users to … Standardized land cover is mapped in 20 classes for both 2006 and 2011. Evergreen forest: areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. This index provides a simple and comprehensive way to visualize change from all 7 dates of land cover in a single layer. NLCD Legend Land Cover Class Descriptions 22 Developed, Low Intensity -Includes areas with a mixture of constructed materials and vegetation. images.). NLCD Code:24 NLCD Class: HIGH INTENSITY DEVELOPED SE Gap Analysis Project - Land Cover Legend Most U.S. Geological Survey (USGS) information resides apartment complexes, row houses and commercial/industrial. Island. Impervious surface layers (currently provided at nominal 5-year intervals) provide information valuable for hydrologic applications, for example. Included in NLCD2016. This is a powerful tool for analyzing the significance of land cover with, for our specific case, land surface temperature (LST). Developed, medium intensity: areas with a mixture of constructed materials and vegetation. Woody wetlands: areas where forest or shrubland vegetation accounts for greater than 20% of vegetative cover and the soil or substrate is periodically saturated with or covered with water. The colored rectangles represent the NLCD points contained within each GOES-16 bounded pixel (red circles). This type can occur with significant other grasses or other grass like plants, and includes sedge tundra and sedge tussock tundra. These areas most commonly include single-family housing units. NLCD 2016 represents the latest evolution of NLCD land cover products focused on providing innovative land cover and land cover change data for the Nation. Impervious surfaces account for 20-49 percent of total cover. Crop vegetation accounts for greater than 20% of total vegetation. Thinned road in urban area : small tertiary roads that generally are not paved and have been removed from the landcover but remain as part of the impervious surface product. These products have Points common to all image pairs were used for classification via decision tree, with cross-validation and boosting options. urban classes and on a decision-tree classification for the rest. NLCD (the National Land Cover Database) is a 30-m Landsat-based land cover Pasture/hay: areas of grasses, legumes, or grass-legume mixtures planted for livestock grazing or the production of seed or hay crops, typically on a perennial cycle. with estimating shrub height and sagebrush height. NLCD provides spatial reference and descriptive data for characteristics of the land surface such as thematic class (for example, urban, agriculture, and forest), percent impervious surface, and percent tree canopy cover. This intermediate change pixel product was generalized using the NLCD Smart Eliminate tool with the following minimum mapping units (mmu) applied: 1 acre (approximately 5 … NLCD 2006 in turn has built upon NLCD 2001 by incorporating land-cover and impervious surface change for the continental United States (Fry et al., 2011, Xian et al., 2011). The USA NLCD Land Cover Change layer shows only the land cover that changed type between 2006 and 2011, displaying areas of no change with a transparent symbol. Note that the impervious layers and tree cover layers for Alaska 2011 The legends are also available as metadata on each image. To illustrate change in percent impervious surface, zonal statistics were performed on spatial data for the change of impervious surface between the years 2001 and 2006. Moss: Alaska only areas dominated by mosses, generally greater than 80% of total vegetation. NLCD Legend … database spanning 8 epochs (1992, 2001, 2004, 2006, 2008, 2011, 2013 and 2016). The original land cover map To access this dataset in Earth Engine, please sign up for Earth Engine Examples include apartment complexes, row houses, and commercial/industrial. Impervious surfaces account for 50-79 percent of the total cover. Examples include apartment complexes, row houses and commercial/industrial. Sedge/herbaceous: Alaska only areas dominated by sedges and forbs, generally greater than 80% of total vegetation. National Land Cover Data Base (NLCD)– is a 16-classes land cover classification scheme. *To view and print the PDF you must obtain and install the Acrobat® Reader, available at no charge from Adobe Systems. Urban classes were excluded, as they are derived from a separate product, the impervious estimation. The impervious surface data are represented as the percent impervious cover for each unique watershed. Impervious surfaces account for 80 to100 percent of the total cover. NLCD Legend Land Cover Class Descriptions Developed, High Intensity Developed, High Intensity - Includes highly developed areas where people reside or work in high numbers. Developed, open space: areas with a mixture of some constructed materials, but mostly vegetation in the form of lawn grasses. The higher the value, the greater the model uncertainty in estimating the canopy value for that cell. Included in NLCD2016. Deciduous forest: areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. NLCD 2016 Shrub Component products characterize the percentage of each Percent Canopy Density, Percent Impervious Surface (Salt Lake and Mesa sites) – Secondary road outside urban area : non-interstate highways. The NLCD consistently quantifies the percent anthropogenic TIA for the NLCD at a 30-meter … U.S. Geological Survey. (Source: NLCD Legend Land Cover Class Descriptions) Value Definition; 11: Open Water - All areas of open water, generally with less than 25% cover or vegetation or soil 12: Perennial Ice/Snow - All areas characterized by a perennial cover of ice and/or snow, generally greater than 25% of total cover. Developed high intensity: highly developed areas where people reside or work in high numbers. Included in NLCD2016. NLCD 2016 updates all previously released versions of impervious products for CONUS (NLCD 2001, NLCD 2006, NLCD 2011) along with a new date of impervious surface for 2016. only have data for parts of Alaska. New for NLCD 2016 is an impervious surface descriptor layer. These areas most commonly include single-family housing units. The symbology uses a 7-class graduated color ramp with thresholds set according to Schueler et al (2009) Reformulated Impervious Cover Model. Grassland/herbaceous: areas dominated by gramanoid or herbaceous vegetation, generally greater than 80% of total vegetation. surface characteristic value tables in the appendices of the AERSURFACE User’s Guide Included in NLCD2016. NLCD products are created by the Multi-Resolution Land Characteristics These areas most commonly include large-lot single-family housing units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion control, or aesthetic purposes. Nonroad impervious surface in urban area. in the public domain and may be used without restriction. The dead plant material proportion in each 30m pixel. Source is available. mrlc,nlcd,usgs,blm, https://developers.google.com/earth-engine/datasets, Ask questions using the google-earth-engine tag, Sign up for the Google Developers newsletter, Acknowledging or Crediting USGS as Information NLCD released its most expansive and detailed database to date in mid-2019, sorting each 30-meter plot of ground in the country into a land cover class – e.g. The classes in the 2016 product legend are given below. This class includes true shrubs, young trees in an early successional stage, or trees stunted from environmental conditions. Impervious surfaces account for less than 20% of total cover. Nonroad impervious surface outside urban area. 1992 data are primarily based on unsupervised classification of Landsat data, NLCD 2016 products include 20 classes of land cover for Alaska, as well as a separate product that defines impervious surfaces in urban areas (usually composed of concrete, asphalt, stone, and metal — widely recognized as a key indicator of environmental quality in urban areas). been produced by USGS in collaboration with the Bureau of Land Management. This class also includes all land being actively tilled. The proportion of sagebrush canopy in each 30m pixel. New for NLCD 2016 is an impervious surface descriptor layer. NLCD Legend Land Cover Class Descriptions: 21: Developed, Open Space - Includes areas with a mixture of some constructed materials, but mostly vegetation in the form of lawn grasses. Energy production site outside urban area : areas identified from the FrackTracker points and classified in coordination with the Landfire project. eight epochs, plus separate images for Alaska, Hawaii, and Puerto Rico in 2001 and 2011. This intermediate change pixel product was generalized using the NLCD Smart Eliminate tool with the following minimum mapping units (mmu) applied: 1 acre (approximately 5 … Open water: areas of open water, generally with less than 25% cover of vegetation or soil. Average height of shrubs. More than 75% of the tree species shed foliage simultaneously in response to seasonal change. Accuracy assessment of NLCD 2006 land cover and impervious surface James D. Wickham a,⁎, Stephen V. Stehman b, Leila Gass c, Jon Dewitz d, Joyce A. Fry d, Timothy G. Wade a … … tip of the Alaskan Panhandle up through the Kenai Peninsula, plus Kodiak This type is often co-associated with grasses, sedges, herbs, and non-vascular vegetation. Primary road outside urban area : interstates and other major roads. This dataset has one image for the continental US for each of the With the production and release of NLCD 2006, MRLC has initiated a shift from land-cover mapping to land-cover monitoring (Fry et al., 2011). Download the NLCD2016 land cover classification legend. Earth Engine is free to use for research, education, and nonprofit use. Because of challenges in comparing NLCD datasets from these two years, we used spatial data calculated by Fry et al. The USGS acknowledges the support of USGS NLCD 2006 Land Cover … The 1992 then return to this page. Impervious surfaces account for 80% to 100% of the total cover. Neither deciduous nor evergreen species are greater than 75% of total tree cover. The classification system used by NLCD2016 is modified from the Anderson Land Cover Classification System*. NLCD 2016 land cover and impervious surface product versions of previous dates must be downloaded for proper comparison. All images except NCLD2011_HI and NLCD2011_PR include the landcover classification scheme described in the 2016 Product Legend. The polygon does not appear to be a “sealed” surface, and therefore its classification as impervious in the reference data could be debated. developed, cropland, wetland – as well as offering information on tree canopy cover, impervious urban surfaces, a roads and energy development layer, and grass/shrub coverage layers for the Western U.S. Shrub/scrub: areas dominated by shrubs less than 5 meters tall with shrub canopy typically greater than 20% of total vegetation. Included in images NLCD2001, NLCD2001_AK, NLCD2001_HI, NLCD2001_PR, NLCD2006, NLCD2011, NLCD2011_AK, and NLCD2016. Impervious surfaces account for less than 20 percent of total cover. Percent of the pixel covered by developed impervious surface. Included in NLCD2016. Impervious surfaces account for 20% to 49% percent of total cover. ... Impervious surfaces account for less than 20% of total cover. Tertiary road outside urban area : any two-lane road. 2018, A New Generation of the United States National Land Cover Database: Requirements, Research Priorities, Design, and Implementation Strategies, p. 108–123. Impervious surfaces, including paved areas such as roads, parking lots, and sidewalks as well as rooftops, prevent water from draining naturally into the ground. landcover,shrub,shrubland, Canopy is never without green foliage. NLCD 2016 offers 7 integrated epochs of land cover for years 2001, 2003, 2006, 2008, 2011, 2013, and 2016. NLCD Legend Land Cover Class Descriptions 23 Developed, Medium Intensity - Includes areas with a mixture of constructed materials and vegetation. Also included in this release are thematic … Included in NLCD2016. NLCD provides spatial reference and descriptive data for characteristics of the land surface such as thematic class (for example, urban, agriculture, and forest), percent impervious surface, and percent tree canopy cover. NLCD Legend Land Cover Class Descriptions: 12: Perennial Ice/Snow - All areas characterized by a perennial cover of ice and/or snow, generally greater than 25% of total cover. These boundings will allow us to calculate statistics relating GOES-16 data to ground parameters (NLCD). These roads have been separated in the western United States so that a better categorization of developed features is represented in the landcover. More than 75% of the tree species maintain their leaves all year. Secondary road in urban area : non-interstate highways. Updating the 2001 National Land Cover Database impervious surface products to 2006 using Landsat imagery change detection methods. information on Acknowledging or Crediting USGS as Information No masking of obvious non-tree areas is performed for this product. Developed classes in these years are directly derived from and updated following the impervious surface cycle. Barren land (rock/sand/clay): areas of bedrock, desert pavement, scarps, talus, slides, volcanic material, glacial debris, sand dunes, strip mines, gravel pits, and other accumulations of earthen material. (2011) and Xian et al. NLCD (the National Land Cover Database) is a 30-m Landsat-based land cover database spanning 8 epochs (1992, 2001, 2004, 2006, 2008, 2011, 2013 and 2016). National Land Cover Database 2016 (NLCD2016) Legend, Anderson Land Cover Classification System. Included in NLCD2016. Average height of sagebrush. These roads have been separated in the western United States so that a better categorization of developed features is represented in the landcover. Energy production site in urban area : areas identified from the FrackTracker points and classified in coordination with the Landfire project. This descriptor layer identifies types of roads, core urban areas, and energy production sites for each impervious pixel to allow deeper analysis of developed features. Included in NLCD2016. Impervious surfaces account for 80 to100 percent of the total cover. Dwarf scrub: Alaska only areas dominated by shrubs less than 20 centimeters tall with shrub canopy typically greater than 20% of total vegetation. The results are many, including an increased burden on stormwater infrastructure, erosion, reduced water quality, 'heat island effects', and both ground-level and water pollution. The bare ground proportion in each 30m pixel. 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