Homer, C., C. Huang, L. Yang, B. Wylie and M. Coan, 2004. Development of a 2001 national land cover database for the United States. Photogrammetric Engineering and Remote Sensing.
The USGS acknowledges the support of Earth Satellite Corporation in development of data in this zone.
The NLCD 2001 was created by partitioning the U.S. into mapping zones. A total of 66 mapping zones were delineated within the conterminous U.S. based on ecoregion and geographical characteristics, edge matching features and the size requirement of Landsat mosaics. Mapping zone 12 encompasses whole or portions of several states including Nevada and California. Questions about the NLCD mapping zone 12 can be directed to the NLCD 2001 land cover mapping team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.
By combining the training data with Landsat spectral data and other ancillary data, percent imperviousness prediction models were developed using a regression tree algorithm (named "Cubist"). All data layers used as input for running the Cubist in order to establish the prediction model for imperviousness are listed in the "Supplemental Information" section. Three ancillary data sets were used for urban/suburban delineation masking, which is essential to confine the imperviousness mapping within the developed areas.
After the best combination of possible input data layers had been determined and the final percent impervious layer produced, the urban mask created was used to eliminate those pixels from the final percent impervious file that fall outside identified impervious surface areas. Thus, the impervious pixels identified within the mask were retained, while all non-impervious surface pixels were removed from the final product. This corrected for any small areas of pixels that may have been included as part of the impervious surface layer because their spectral signature was not covered in the Cubist modeling process. Finally, visual inspection of imperviousness layer was made with limited manual editing to eliminate non-urban areas based on area of interest delineated by the mapping team.
Acquisition dates of Landsat ETM+ (TM) scenes used for land cover classification in zone 12 are as follows:
SPRING-
Index 1 for Path 39/Row 34 on 05/03/00 = Scene_ID 7039034000012450
Index 2 for Path 40/Row 31 on 04/08/00 = Scene_ID 7040031000009950
Index 2 for Path 40/Row 32 on 04/08/00 = Scene_ID 7040032000009950
Index 3 for Path 40/Row 33 on 04/24/00 = Scene_ID 7040033000011550
Index 2 for Path 40/Row 31 on 04/08/00 = Scene_ID 7040031000009950
Index 4 for Path 41/Row 31 on 05/04/01 = Scene_ID 7041031000112450
Index 4 for Path 41/Row 32 on 05/04/01 = Scene_ID 7041032000112450
Index 4 for Path 41/Row 33 on 05/04/01 = Scene_ID 7041033000112450
Index 5 for Path 41/Row 34 on 04/08/03 = Scene_ID 7041034000309850
Index 6 for Path 42/Row 31 on 05/11/01 = Scene_ID 7042031000113150
Index 7 for Path 42/Row 32 on 03/21/00 = Scene_ID 7042032000008150
Index 8 for Path 42/Row 33 on 04/06/00 = Scene_ID 7042033000009750
Index 8 for Path 42/Row 34 on 04/06/00 = Scene_ID 7042034000009750
Index 9 for Path 43/Row 31 on 04/29/00 = Scene_ID 7043031000012050
Index 9 for Path 43/Row 32 on 04/29/00 = Scene_ID 7043032000012050
Index10 for Path 43/Row 33 on 05/31/00 = Scene_ID 7043033000015250
Index11 for Path 44/Row 32 on 05/12/02 = Scene_ID 7044032000213250
LEAF ON (Summer)-
Index 1 for Path 39/Row 34 on 05/03/00 = Scene_ID 7039034000012450
Index 2 for Path 40/Row 31 on 07/13/00 = Scene_ID 7040031000019550
Index 2 for Path 40/Row 32 on 07/13/00 = Scene_ID 7040032000019550
Index 3 for Path 40/Row 33 on 08/14/00 = Scene_ID 7040033000022750
Index 4 for Path 40/Row 34 on 06/11/00 = Scene_ID 7040034000016350
Index 5 for Path 41/Row 31 on 07/10/02 = Scene_ID 7041031000219150
Index 6 for Path 41/Row 32 on 07/20/00 = Scene_ID 7041032000020250
Index 7 for Path 41/Row 33 on 07/20/00 = Scene_ID 7041033000020250
Index 7 for Path 41/Row 34 on 07/20/00 = Scene_ID 7041034000020250
Index 8 for Path 42/Row 31 on 07/27/00 = Scene_ID 7042031000020950
Index 8 for Path 42/Row 32 on 07/27/00 = Scene_ID 7042032000020950
Index 8 for Path 42/Row 33 on 07/27/00 = Scene_ID 7042033000020950
Index 8 for Path 42/Row 34 on 07/27/00 = Scene_ID 7042034000020950
Index 9 for Path 43/Row 31 on 06/30/99 = Scene_ID 7043031009918150
Index10 for Path 43/Row 32 on 07/16/99 = Scene_ID 7043032009919750
Index11 for Path 43/Row 33 on 07/18/00 = Scene_ID 7043033000020050
Index12 for Path 44/Row 32 on 07/28/01 = Scene_ID 7044032000120950
LEAF-OFF (Fall)-
Index 1 for Path 39/Row 34 on 10/08/99 = Scene_ID 7039034009928150
Index 2 for Path 40/Row 31 on 10/15/99 = Scene_ID 7040031009928850
Index 3 for Path 40/Row 32 on 09/29/99 = Scene_ID 7040032009927250
Index 2 for Path 40/Row 33 on 10/15/99 = Scene_ID 7040033009928850
Index 2 for Path 40/Row 34 on 10/15/99 = Scene_ID 7040034009928850
Index 4 for Path 41/Row 31 on 09/04/99 = Scene_ID 7041031009924750
Index 4 for Path 41/Row 32 on 09/04/99 = Scene_ID 7041032009924750
Index 5 for Path 41/Row 33 on 10/08/00 = Scene_ID 7041033000028250
Index 5 for Path 41/Row 34 on 10/08/00 = Scene_ID 7041034000028250
Index 6 for Path 42/Row 31 on 09/27/99 = Scene_ID 7042031009927050
Index 7 for Path 42/Row 32 on 09/11/99 = Scene_ID 7042032009925450
Index 6 for Path 42/Row 33 on 09/27/99 = Scene_ID 7042033009927050
Index 8 for Path 42/Row 34 on 10/18/01 = Scene_ID 7042034000129150
Index 9 for Path 43/Row 31 on 10/06/00 = Scene_ID 7043031000028050
Index10 for Path 43/Row 32 on 10/20/99 = Scene_ID 7043032009929350
Index 9 for Path 43/Row 33 on 10/06/00 = Scene_ID 7043033000028050
Index11 for Path 44/Row 32 on 10/19/02 = Scene_ID 7044032000229250
Landsat data and ancillary data used for the imperviousness prediction -
Data Type of DEM composed of 1 band and a Continuous Variable Type.
Data Type of Slope composed of 1 band and a Continuous Variable Type.
Data Type of Aspect composed of 1 band of Categorical Variable Type.
Data type of Position Index composed of 1 band of Continuous Variable Type.
Ancillary data used for urban area masking include:
1. NOAA Defense Meteorological Satellite Program 1 km city light data (1 band)
2. MRLC 1992 classification (1 band)
3. TIGER 2000 roads (1 band)