Metadata for 1992 National Land Cover Data (NLCD) for Montana Metadata for 1992 National Land Cover Data (NLCD) for Montana
Identification Information:
Citation:
Originator: U.S. Geological Survey
Publication date: 2000
Title: 1992 National Land Cover Data (NLCD) for Montana
Edition: 2000-05
Publication place: Helena, Montana
Publisher: Montana State Library
Online linkage: https://ftpgeoinfo.msl.mt.gov/Data/Spatial/NonMSDI/Raster/NLCD_1992.zip
Larger Work Citation:
Title: 2016 National Land Cover Data
Online linkage: https://mslservices.mt.gov/Geographic_Information/Data/DataList/datalist_Details.aspx?did={7670ad63-9233-4754-87d6-da0138c7f8e6}
Browse graphic file name: https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Thumbnails/20031113_426_thumb.jpg
Browse graphic file description: Thumbnail image of National Land Cover Dataset 1992 map
Browse graphic file name: https://ftpgeoinfo.msl.mt.gov/Documents/Maps/Individual/20031113_426_nlcd.gif
Browse graphic file description: National Land Cover Dataset 1992 map

Abstract:
This is the 1992 National Land Cover Data Set for Montana, projected to Montana State Plane Coordinates and converted to TIFF format.

The National Land Cover Data Set was produced as part of a cooperative project between the U.S. Geological Survey (USGS) and the U.S. Environmental Protection Agency (USEPA) to produce a consistent, land cover data layer for the conterminous U.S. based on 30-meter Landsat thematic mapper (TM) data. National Land Cover Data (NLCD) was developed from TM data acquired by the Multi-resoultion Land Characterization (MRLC) Consortium. The MRLC Consortium is a partnership of federal agencies that produce or use land cover data. Partners include the USGS (National Mapping, Biological Resources, and Water Resources Divisions), USEPA, the U.S. Forest Service, and the National Oceanic and Atmospheric Administration.

The Montana NLCD set was produced as part of a project area encompassing portions of Federal Regions 8 and 10. This data set was produced under the direction of the MRLC Regional Land Cover Characterization Project of the USGS EROS Data Center (EDC), Sioux Falls, SD. Questions about the data set can be directed to the MRLC Regional Team at (605) 594-6114 or mrlc@edcmail.cr.usgs.gov.

This data set was extracted from the larger regional data set. State boundaries from the USGS 1:100,000 Digital Line Graph (DLG) series were used as the basis for extracting the state data. In many instances, the precision of the boundaries in the 1:100,000 DLG data does not match the spatial precision of the Landsat TM data. To overcome the possibility of data being lost in the extraction process, a 300 meter (10 pixel) buffer was added to the state boundary used to extract the state data.

The base data set for this project was leaves-off Landsat TM data, nominal-1992 acquisitions. Other ancillary data layers included leaves-on TM, USGS 3-arc second Digital Terrain Elevation Data (DTED) and derived slope, aspect and shaded relief, Bureau of the Census population and housing density data, USGS land use and land cover (LUDA), and National Wetlands Inventory (NWI) data if available.

Caveats and Concerns:
Both irrigated and dryland agriculture are practiced in this region.

In the dryland areas small grains predominate; fields are classified as fallow when there is no evidence of visible vegetation indicating a prescribed alternation between cropping and tillage. Crop types in the irrigated areas were difficult to reliably distinguish; row crops are likely to be under represented where no field observations or other ancillary information was incorporated.
Purpose:
Many federal agencies, including the U.S. Geological Survey, the U.S. Environmental Protection Agency, the U.S. Forest Service, the National Oceanic and Atmospheric Administration, state goverments, and various environmental groups need up-to-date intermediate scale land cover data.

The most recent intermediate scale land cover data set generated for the conterminous United States was developed by the USGS in the 1970's.

Although this data set is probably still adequate for some applications, many land cover changes have occurred since the data set was compiled. The main objective of this project is to generate a relatively current, consistent, seamless, and accurate land cover data set for the conterminous United States.

Potential uses of land cover data are many and varied, and include assessing ecosystem status and health, modeling nutrient and pesticide runoff, understanding spatial patterns of biodiversity, land use planning, deriving landscape pattern metrics, and developing land management policy.

Time period of content:
Beginning date: 05/26/1985
Ending date: 06/19/1995
Currentness reference: ground condition
Status:
Progress: Complete
Maintenance and update frequency:
The MRLC is preparing NLCD 2001, whose release date has not been determined. See http://landcover.usgs.gov/natlandcover_2000.html
Access constraints: None
Use constraints:
The Montana State Library provides this product/service for informational purposes only. The Library did not produce it for, nor is it suitable for legal, engineering, or surveying purposes. Consumers of this information should review or consult the primary data and information sources to ascertain the viability of the information for their purposes. The Library provides these data in good faith but does not represent or warrant its accuracy, adequacy, or completeness. In no event shall the Library be liable for any incorrect results or analysis; any direct, indirect, special, or consequential damages to any party; or any lost profits arising out of or in connection with the use or the inability to use the data or the services provided. The Library makes these data and services available as a convenience to the public, and for no other purpose. The Library reserves the right to change or revise published data and/or services at any time.

The user must have a firm understanding of how the datasets were compiled and the resulting limitations of these data. The National Land Cover Dataset was compiled from Landsat satellite TM imagery (circa 1992) with a spatial resolution of 30 meters and supplemented by various ancillary data (where available). The analysis and interpretation of the satellite imagery was conducted using very large, sometimes multi-state image mosaics (i.e. up to 18 Landsat scenes). Using a relatively small number of aerial photographs for 'ground truth', the thematic interpretations were necessarily conducted from a spatially-broad perspective. Thus, the reliability of the data is greatest at the state or multi-state level.

Important Caution Advisory
With this in mind, users are cautioned to carefully scrutinize the data to see if they are of sufficient reliability before attempting to use the dataset for larger-scale or local analyses. This evaluation must be made remembering that the NLCD represents conditions in the early 1990s.
Point of contact:
Montana State Library
P.O. Box 201800
Helena, Montana 59620-1800


Telephone: 406-444-5354
TDD/TTY telephone: Montana Relay 711
Fax: 406-444-0266
E-Mail: geoinfo@mt.gov


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Data Quality Information:
Attribute accuracy report:
The accuracy of this data has not been assesed for Montana. See http://landcover.usgs.gov/accuracy/ for the status of accuracy assement of the NLCD.

The MRLC's general discussion of the accuracy of the NLCD follows: While we believe that the approach taken has yielded a very good general land cover classification product for a large region, it is important to indicate to the user where there might be some potential problems. The biggest concerns are listed below:

1) Some of the TM data sets are not temporally ideal. Leaves-off data sets are heavily relied upon for discriminating between hay/pasture and row crop, and also for discriminating between forest classes. The success of discriminating between these classes using leaves-off data sets hinges on the time of data acquisition. When hay/pasture areas are non-green, they are not easily distinguishable from other agricultural areas using remotely sensed data. However, there is a temporal window during which hay and pasture areas green upbefore most other vegetation (excluding evergreens, which have different spectral properties); during this window these areas are easily distinguishable from other crop areas. The discrimination between hay/pasture and deciduous forest is likewise optimized by selecting data in a temporal window where deciduous vegetation has yet to leaf out. It is difficult to acquire a single-date of imagery (leaves-on or leaves-off) that adequately differentiates between both deciduous/hay and pasture and hay-pasture/row crop.

2) The data sets used cover a range of years (see data sources), and changes that have taken place across the landscape over the time period may not have been captured. While this is not viewed as a major problem for most classes, it is possible that some land cover features change more rapidly than might be expected (e.g. hay one year, row crop the next).

3) Wetlands classes are extremely difficult to extract from Landsat TM spectral information alone. The use of ancillary information such as National Wetlands Inventory (NWI) data is highly desirable. We relied on GAP, LUDA, or proximity to streams and rivers as well as spectral data to delineate wetlands in areas without NWI data.

4) Separation of natural grass and shrub is problematic. Areas observed on the ground to be shrub or grass are not always distinguishable spectrally. Likewise, there was often disagreement between LUDA and GAP on these classes.

Horizontal Positional Accuracy Report:
Each Landsat Thematic Mapper image used to create the NLCD was precision terrain-corrected using 3-arc-second digital terrain elevation data (DTED), and georegistered using ground control points. This resulted in a root mean square registration error of less than 1 pixel (30 meters).

Lineage:
Source information:
Originator: U.S. Geological Survey
Publication date: 2000
Title: National Land Cover Data Set, Montana
Edition: 2000-05
Source contribution:
The data set is a re-formatted version of this source. The dates of the source Landsat scenes follows:
LEAF OFF:
Path Row Date Path Row Date
034 028 19 Jun 89 034 029 19 Jun 89
035 026 19 Jun 95 035 027 10 Jun 92
035 028 10 Jun 92 035 029 10 Jun 92
036 026 15 Jun 91 036 027 06 Jun 88
036 028 09 Jun 89 036 029 15 Jun 91
037 026 11 Jun 87 037 027 10 May 93
037 028 10 May 93 037 029 28 May 88
038 026 27 Jun 88 038 027 26 May 88
038 028 30 Jun 89 038 029 30 May 86
039 026 04 Jun 88 039 027 04 Jun 88
039 028 04 Jun 88 039 029 05 May 92
040 026 28 May 86 040 027 28 May 86
040 028 28 May 86 040 029 13 Jun 86
041 026 09 Jun 86 041 027 03 May 92
041 028 24 May 88 042 026 16 Jun 88
042 027 26 May 86
LEAF ON:
Path Row Date Path Row Date
034 028 09 Aug 93 034 029 09 Aug 93
035 026 16 Aug 93 035 027 16 Aug 93
035 028 16 Aug 93 035 029 16 Aug 93
036 026 07 Aug 93 036 027 07 Aug 93
036 028 07 Aug 93 036 029 04 Aug 92
037 026 14 Aug 93 037 027 14 Aug 93
037 028 14 Aug 93 037 029 28 Sep 92
038 026 22 Sep 93 038 027 22 Sep 93
038 028 22 Sep 93 038 029 22 Sep 93
039 026 10 Sep 92 039 027 09 Aug 92
039 028 09 Aug 92 039 029 09 Aug 92
040 026 19 Aug 93 040 027 20 Jul 88
040 028 19 Aug 93 040 029 13 Jul 92
041 026 28 Aug 88 041 027 21 Aug 91
041 028 21 Aug 91 042 026 14 Aug 92
042 027 14 Aug 92
Beginning date: 05/26/1985
Ending date: 06/19/1995

Process step:
This is the MRLC's description of some of the methods used to create the NLCD:

The project is being carried out on the basis of 10 Federal Regions that make up the conterminous United States; each region is comprized of multiple states; each region is processed in subregional units that are limited to the area covered by no more than 18 Landsat TM scenes. The general NLCD procedure is to:
(1) mosaic subregional TM scenes and classify them using an unsupervised clustering algorithm,
(2) interpret and label the clusters/classes using aerial photographs as reference data,
(3) resolve the labeling of confused clusters/classes using the appropriate ancillary data source(s), and
(4) incorporate land cover information from other data sets and perform manual edits to augment and refine the "basic" classification developed above.

Two seasonally distinct TM mosaics are produced, a leaves-on version (summer) and a leaves-off (spring/fall) version. TM bands 3 4 5 and 7 are mosaicked for both the leaves-on and leaves-off versions. For mosaicking purposes, a base scene is selected for each mosaic and the other scenes are adjusted to mimic spectral properties of the base scene using histogram matching in regions of spatial overlap.

Following mosaicking, either the leaves-off version or leaves-on version is selected to be the "base" for the land cover mapping process. The 4 TM bands of the "base" mosaic are clustered to produce a single 100-class image using an unspervised clustering algorithm. Each of the spectrally distinct clusters/classes is then assigned to one or more Anderson level 1 and 2 land cover classes using National High Altitude Photography program (NHAP) and National Aeria l Photography program (NAPP) aerial photographs as a reference. Almost invariably, individual spectral clusters/classes are confused between two or more land cover classes.

Separation of the confused spectral clusters/classes into appropriate NLCD class is accomplished using ancillary data layers. Standard ancillary data layers include: the "non-base" mosaic TM bands and 100-class cluster image; derived TM normalized vegetation index (NDVI), various TM band ratios, TM date bands; 3-arc second Digital Terrain Elevation Data (DTED) and derived slope, aspect and shaded relief; population and housing density data; USGS land use and land cover (LUDA); and National Wetlands Inventory (NWI) data if available.

Other ancillary data sources may include soils data, unique state or regional land cover data sets, or data from other federal programs such as the National Gap Analysis Program (GAP) of the USGS Biological Resources Division (BRD). For a given confused spectral cluster/class, digital values of the various ancillary data layers are compared to determine:
(1) which data layers are the most effective for splitting the confused cluster/class into the appropriate NLCD class, and
(2) the appropriate layer thresholds for making the split(s). Models are then developed using one to several ancillary data layers to split the confused cluster/class into the NLCD class. For example, a population density threshold is used to separate high-intensity residential areas from commercial/industrial /transportation. Or a cluster/class might be confused between row crop and grasslands. To split this particular cluster/class, a TM NDVI threshold might be identified and used with an elevation threshold in a class-spliting model to make the appropriate NLCD class assignments. A purely spectral example is using the temporally opposite TM layers to discriminate confused cluster/classes such as hay pasture vs. row crops and deciduous forests vs. evergreen forests; simple thresholds that contrast the seasonal differences in vegetation between leaves-on vs. leaves-off.

Not all cluster/class confusion can be successfully modeled out. Certain classes such as urban/recreational grasses or quarries/strip mines/gravel pits that are not spectrally unique require manual editing. These class features are typically visually identified and then reclassified using on-screen digitizing and recoding. Other classes such as wetlands require the use of specific data sets such as NWI to provide the most accurate classification. Areas lacking NWI data are typically subset out and modeling is used to estimate wetlands in these localized areas. The final NLCD product results from the classification (interpretation and labeling) of the 100-class "base"cluster mosaic using both automated and manual processes, incorporating both spectral and conditional data layers.
Process date: 06/01/1999
Process step:
Convert the downloaded National Land Cover data file into ESRI GRID format and project the data to Montana State Plane Coordinates.
Process date: 2000
Process step: Convert the data to TIFF format and create a colormap.
Process date: 11/04/2013
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Spatial Data Organization Information:
Raster object information:
Raster object type: Pixel
Row count: 17696
Column count: 30638
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Spatial Reference Information:
Horizontal coordinate system definition:
Grid coordinate system name: State Plane Coordinate System 1983
SPCS zone identifier: 2500
Lambert conformal conic:
Standard parallel: 45
Standard parallel: 49
Longitude of central meridian: -109.5
Latitude of projection origin: 44.25
False easting: 600000.00000
False northing: 0.00000
Planar distance units: meters
Geodetic model:
Horizontal datum name: North American Datum of 1983
Ellipsoid name: Geodetic Reference System 80
Semi-major axis: 6378137
Denominator of flattening ratio: 298.257
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Entity and Attribute Information:
Entity type label: NLCD_1992.tif.vat.dbf
Entity type definition: Value Attribute Table

Attribute label: OID
Attribute definition: Database sequence number

Attribute label: VALUE
Attribute definition: Land Cover Code


Attribute
Value
Definition of
Attribute Value
11 Open Water
12 Perennial Ice/Snow
21 Low Intensity Residential
22 High Intensity Residential
23 Commercial/Industrial/Transportation
31 Bare Rock/Sand/Clay
32 Quarries/Strip Mines/Gravel Pits
33 Transitional
41 Deciduous Forest
42 Evergreen Forest
43 Mixed Forest
51 Shrubland
61 Orchards/Vineyards/Other
71 Grasslands/Herbaceous
81 Pasture/Hay
82 Row Crops
83 Small Grains
84 Fallow
85 Urban/Recreational Grasses
91 Woody Wetlands
92 Emergent Herbaceous Wetlands

Attribute label: COUNT
Attribute definition: Number of grid cells with this value in the dataset

Attribute label: LandCover
Attribute definition: Land Cover Description

Entity and attribute overview:
NLCD Land Cover Classification System Land Cover Class Definitions

Water - All areas of open water or permanent ice/snow cover.
11. Open Water - All areas of open water; typically 25 percent or greater cover of water (per pixel).

12. Perennial Ice/Snow - All areas characterized by year-long cover of ice and/or snow.

Developed - Areas characterized by a high percentage (30 percent or greater) of constructed materials (e.g. asphalt, concrete, buildings, etc).
21. Low Intensity Residential - Includes areas with a mixture of constructed materials and vegetation. Constructed materials account for 30-80 percent of the cover. Vegetation may account for 20 to 70 percent of the cover. These areas most commonly include single-family housing units. Population densities will be lower than in high intensity residential areas.

22. High Intensity Residential - Includes highly developed areas where people reside in high numbers. Examples include apartment complexes and row houses. Vegetation accounts for less than 20 percent of the cover. Constructed materials account for 80 to100 percent of the cover.

23. Commercial/Industrial/Transportation - Includes infrastructure (e.g. roads, railroads, etc.) and all highly developed areas not classified as High Intensity Residential.

Barren - Areas characterized by bare rock, gravel, sand, silt, clay, or other earthen material, with little or no "green" vegetation present regardless of its inherent ability to support life. Vegetation, if present, is more widely spaced and scrubby than that in the "green" vegetated categories; lichen cover may be extensive.

31. Bare Rock/Sand/Clay - Prennially barren areas of bedrock, desert pavement, scarps, talus, slides, volcanic material, glacial debris, beaches, and other accumulations of earthen material.

32. Quarries/Strip Mines/Gravel Pits - Areas of extractive mining activities with significant surface expression.

33. Transitional - Areas of sparse vegetative cover (less than 25 percent of cover) that are dynamically changing from one land cover to another, often because of land use activities. Examples include forest clearcuts, a transition phase between forest and agricultural land, the temporary clearing of vegetation, and changes due to natural causes (e.g. fire, flood, etc.).

Forested Upland - Areas characterized by tree cover (natural or semi-natural woody vegetation, generally greater than 6 meters tall); tree canopy accounts for 25-100 percent of the cover.
41. Deciduous Forest - Areas dominated by trees where 75 percent or more of the tree species shed foliage simultaneously in response to seasonal change.

42. Evergreen Forest - Areas dominated by trees where 75 percent or more of the tree species maintain their leaves all year. Canopy is never without green foliage.

43. Mixed Forest - Areas dominated by trees where neither deciduous nor evergreen species represent more than 75 percent of the cover present. Shrubland - Areas characterized by natural or semi-natural woody vegetation with aerial stems, generally less than 6 meters tall, with individuals or clumps not touching to interlocking. Both evergreen and deciduous species of true shrubs, young trees, and trees or shrubs that are small or stunted because of environmental conditions are included.

51. Shrubland - Areas dominated by shrubs; shrub canopy accounts for 25-100 percent of the cover. Shrub cover is generally greater than 25 percent when tree cover is less than 25 percent. Shrub cover may be less than 25 percent in cases when the cover of other life forms (e.g. herbaceous or tree) is less than 25 percent and shrubs cover exceeds the cover of the other life forms.

Non-natural Woody - Areas dominated by non-natural woody vegetation; non-natural woody vegetative canopy accounts for 25-100 percent of the cover. The non-natural woody classification is subject to the availability of sufficient ancillary data to differentiate non-natural woody vegetation from natural woody vegetation.
61. Orchards/Vineyards/Other - Orchards, vineyards, and other areas planted or maintained for the production of fruits, nuts, berries, or ornamentals.

Herbaceous Upland - Upland areas characterized by natural or semi-natural herbaceous vegetation; herbaceous vegetation accounts for 75-100 percent of the cover.
71. Grasslands/Herbaceous - Areas dominated by upland grasses and forbs. In rare cases, herbaceous cover is less than 25 percent, but exceeds the combined cover of the woody species present. These areas are not subject to intensive management, but they are often utilized for grazing.

Planted/Cultivated - Areas characterized by herbaceous vegetation that has been planted or is intensively managed for the production of food, feed, or fiber; or is maintained in developed settings for specific purposes. Herbaceous vegetation accounts for 75-100 percent of the cover.
81. Pasture/Hay - Areas of grasses, legumes, or grass-legume mixtures planted for livestock grazing or the production of seed or hay crops.

82. Row Crops - Areas used for the production of crops, such as corn, soybeans, vegetables, tobacco, and cotton.

83. Small Grains - Areas used for the production of graminoid crops such as wheat, barley, oats, and rice.

84. Fallow - Areas used for the production of crops that are temporarily barren or with sparse vegetative cover as a result of being tilled in a management practice that incorporates prescribed alternation between cropping and tillage.

85. Urban/Recreational Grasses - Vegetation (primarily grasses) planted in developed settings for recreation, erosion control, or aesthetic purposes. Examples include parks, lawns, golf courses, airport grasses, and industrial site grasses. Wetlands - Areas where the soil or substrate is periodically saturated with or covered with water as defined by Cowardin et al.

91. Woody Wetlands - Areas where forest or shrubland vegetation accounts for 25-100 percent of the cover and the soil or substrate is periodically saturated with or covered with water.

92. Emergent Herbaceous Wetlands - Areas where perennial herbaceous vegetation accounts for 75-100 percent of the cover and the soil or substrate is periodically saturated with or covered with water.
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Distribution Information:
Distributor:
Montana State Library
PO Box 201800
Helena, MT 59620-1800


Telephone: 406-444-5354
Telephone: 406-444-5354
TDD/TTY telephone: Montana Relay 711
Fax: 406-444-0266
E-Mail: geoinfo@mt.gov
E-Mail: geoinfo@mt.gov


Resource description: Downloadable Data


Distribution liability:
The Montana State Library provides this product/service for informational purposes only. The Library did not produce it for, nor is it suitable for legal, engineering, or surveying purposes. Consumers of this information should review or consult the primary data and information sources to ascertain the viability of the information for their purposes. The Library provides these data in good faith but does not represent or warrant its accuracy, adequacy, or completeness. In no event shall the Library be liable for any incorrect results or analysis; any direct, indirect, special, or consequential damages to any party; or any lost profits arising out of or in connection with the use or the inability to use the data or the services provided. The Library makes these data and services available as a convenience to the public, and for no other purpose. The Library reserves the right to change or revise published data and/or services at any time.

Standard order process:
Digital form:
Format name: GeoTIFF
megabytes
Online option:
https://ftpgeoinfo.msl.mt.gov/Data/Spatial/NonMSDI/Raster/NLCD_1992.zip
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Metadata Reference Information:
Metadata date: 01/21/2014
Metadata review date: 04/17/2013
Metadata review date: 09/29/2004
Metadata review date: 04/25/2003
Metadata contact:
Montana State Library
PO Box 201800
Helena, Montana 59620-1800


Telephone: 406-444-5354
TDD/TTY telephone: Montana Relay 711
Fax: 406-444-0266
E-Mail: geoinfo@mt.gov


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