National Land Cover Database 2011

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Introduction

The National Land Cover Database 2011 (NLCD 2011) is the most recent national land cover product created by the Multi-Resolution Land Characteristics (MRLC) Consortium ( http://http://www.mrlc.gov ). NLCD 2011 is based primarily on a decision-tree classification of circa 2011 Landsat satellite data.

The database consists of a 16-class land cover classification scheme, which has been mapped to roughness lengths for use in windPRO.

Coverage

This dataset covers the United States with a spatial resolution of 30 m.

Legends

The NLCD 2011 dataset has 16 different categories that EMD has mapped in to a suggested roughness length, z0.

Table: NLCD 2011 with Roughness Classification Data by EMD
ID Land Cover Type Land Cover Description EMD Roughness Length
11 Open Water Areas of open water, generally with less than 25% cover of vegetation or soil. z0=0.0000
12 Perennial Ice/Snow Areas characterized by a perennial cover of ice and/or snow, generally greater than 25% of total cover. z0=0.0000
21 Developed, Open Space Areas with a mixture of some constructed materials, but mostly vegetation in the form of lawn grasses. Impervious surfaces account for less than 20% of total cover. 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. z0=0.40000
22 Developed, Low Intensity Areas with a mixture of constructed materials and vegetation. Impervious surfaces account for 20% to 49% percent of total cover. These areas most commonly include single-family housing units. z0=0.40000
23 Developed, Medium Intensity Areas with a mixture of constructed materials and vegetation. Impervious surfaces account for 50% to 79% of the total cover. These areas most commonly include single-family housing units. z0=0.40000
24 Developed High Intensity Highly developed areas where people reside or work in high numbers. Examples include apartment complexes, row houses and commercial/industrial. Impervious surfaces account for 80% to 100% of the total cover. z0=0.80000
31 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. Generally, vegetation accounts for less than 15% of total cover. z0=0.00240
41 Deciduous Forest Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. More than 75% of the tree species shed foliage simultaneously in response to seasonal change. z0=0.40000
42 Evergreen Forest Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. More than 75% of the tree species maintain their leaves all year. Canopy is never without green foliage. z0=0.40000
43 Mixed Forest Areas dominated by trees generally greater than 5 meters tall, and greater than 20% of total vegetation cover. Neither deciduous nor evergreen species are greater than 75% of total tree cover. z0=0.40000
51 Dwarf Scrub Alaska only areas dominated by shrubs less than 20 centimeters tall with shrub canopy typically greater than 20% of total vegetation. This type is often co-associated with grasses, sedges, herbs, and non-vascular vegetation. z0=0.03000
52 Shrub/Scrub Areas dominated by shrubs; less than 5 meters tall with shrub canopy typically greater than 20% of total vegetation. This class includes true shrubs, young trees in an early successional stage or trees stunted from environmental conditions. z0=0.10000
71 Grassland/Herbaceous Areas dominated by gramanoid or herbaceous vegetation, generally greater than 80% of total vegetation. These areas are not subject to intensive management such as tilling, but can be utilized for grazing. z0=0.03000
72 Sedge/Herbaceous Alaska only areas dominated by sedges and forbs, generally greater than 80% of total vegetation. This type can occur with significant other grasses or other grass like plants, and includes sedge tundra, and sedge tussock tundra. z0=0.03000
73 Lichens Alaska only areas dominated by fruticose or foliose lichens generally greater than 80% of total vegetation. z0=0.00240
74 Moss Alaska only areas dominated by mosses, generally greater than 80% of total vegetation. z0=0.00240
81 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. Pasture/hay vegetation accounts for greater than 20% of total vegetation. z0=0.03000
82 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. Crop vegetation accounts for greater than 20% of total vegetation. This class also includes all land being actively tilled. z0=0.03000
90 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. z0=0.40000
95 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. z0=0.10000

Citation

Jin, S., Yang, L., Danielson, P., Homer, C., Fry, J., and Xian, G. 2013. A comprehensive change detection method for updating the National Land Cover Database to circa 2011. Remote Sensing of Environment, 132: 159 – 175.

External Link

http://www.mrlc.gov/nlcd2011.php