US NLCD

National Land Cover Database (NLCD) is a Landsat TM derived classification of the United States. It has a nominal resolution of 30 m. The first data set was created in 1995 from circa 1992 imagery and was followed by 2001 NLCD and then NLCD 2006, along with version 2 of NLCD 2001. NLCD 2011 was released in April 2014.

Download the data and store so MICRODEM can recognize it:

From the National Map (larger tiles and more of them possible; you can get 3x3� tiles or state coverage) or
MLRC.

NLCD for Annapolis, MD

Note the greater number of categories in the 200/2006/2011 version (especially coastal wetlands), and greater urban detail.

NLCD 1992/2001 Changes

Currently requires deleting the PRJ file that comes with the Geotiff from the USGS Seamless Server, and using the registration in the Tiff file, or not unzipping the file.
Because of the conical projection, some of the operations that define a box based on lat/long will have anomalies in operations. You should consider this for any analysis you do with this data set, and might want to reproject the data.

NLCD 1992

NLCD 1992 classes defined

(USGS definitions on Web)

NLCD 2001/2006/2011

NLCD 2001 Classes defined

NLCD 2001 overview on web

(USGS Class definitions on web)

Allows you to open Land Cover from the main toolbar. You can do the following on the Calculate menu. Both of these options require that the NLCD data be indexed in the integrated database, but you can perform the operations on any open map.

NLCD Classification: roam over the map and see the NLCD category on the right edge of the status bar.
NLCD Box: outline a box, and see the percentage of each category in the box.

Mask DEM/grid with NLCD.

Co-occurrence matrix to see changes from one time period to another

We have noticed some anomalies in the NLCD classifications; single points can be off. Consider NLCD an area average.

There is a canopy dataset.

Legends for NLCD classification, on File menu.

NLCD References

Vogelmann, J.E., S.M. Howard, L. Yang, C.R. Larson, B.K. Wylie, N. Van Driel, 2001, Completion of the 1990s National Land Cover Data Set for the Conterminous United States from Landsat Thematic Mapper Data and Ancillary Data Sources: Photogrammetric Engineering & Remote Sensing, vol.67, p.650-652.
Collin Homer, Jon Dewitz, Joyce Fry, Michael Coan, Nazmul Hossain, Charles Larson, Nate Herold, Alexa McKerrow, J. Nick VanDriel, and James Wickham, 2007, Completion of the 2001 National Land Cover Database for the Conterminous United States: Photogrammetric Engineering & Remote Sensing, vol.73, no.4, p.337-341.
Fry, J.A., Xian, G., Jin, S., Dewitz, J.A., and 5 others, 2011, Completion of the 2006 National Land Cover Database for the Conterminous United States: Photogrammetric Engineering & Remote Sensing, vol.77, no.9, p.858-864.
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.

Last revision 7/1/2014