For information regarding requirement for publishing your data in the GeoPortal. Please see the "Guide to Creating and Editing Metadata in ArcGIS for Publishing to the MSDIS GeoPortal".
MSDIS serves more than 12,000 data files via FTP. The files have been zipped or gzipped for faster downloading. Gzip compresses ASCII files by about 70%. If you are unfamiliar with gzip or need to download software able to decompress gzipped files, check out the ZIP HELP PAGE. Examples of how to use GNU's gzip program are also available.
Some of the data on the FTP server are organized by Geography i.e. by State or by County extent but MSDIS is transitioning to a new FTP structure based on ISO categories. These data can easily be accessed in three main ways:
1. Via the Geoportal (http://msdisweb.missouri.edu/geoportal/)
2. Via custom web interface
to the FTP server using a web browser
Many of the datasets served by MSDIS have simple web interfaces to allow easy location of data with links to the FTP location for download. The "Data" index page under the "Data" tab of this page contains links to all of these interfaces.
3. Directly from the FTP server
using a web browser or FTP client software or using command
If you are comfortable navigating an FTP server you can do so. Just choose your method, either from your web browser, from FTP client software such as WS-FTP or from the Command prompt. The URL of the public area of MSDIS FTP is ftp://msdis.missouri.edu/pub/
Some of the GIS data available from MSDIS are ArcInfo interchange files which are used to transfer coverages, INFO data files, text files such as AML macros, and other ArcInfo files between various machines. An interchange file contains all coverage information and appropriate INFO file information in a fixed-length, ASCII format. It can be fully or partially compressed and uncompressed ASCII depending upon the EXPORT option used.
Although MSDIS is moving away from ArcInfo Interchange files, some files are in export (.e00) format. Tabular datasets are available in INFO and .dbf formats. You will need ArcGIS or ArcView from ESRI, CAD, mapping or Geographic Information System software that can read ArcInfo export files to use the datasets.
The files have been gzipped (compressed) for faster downloading. Gzip compresses ASCII files by about 70%. If you are unfamiliar with gzip or need to download software able to decompress gzipped files, check out the ZIP HELP PAGE.
We receive many enquires regarding the lack of availability of data in Shapefile format for use with ArcView. Currently, only a few shapefiles are available. However, it is a straightforward process to bring a ArcInfo interchange file into ArcView using the Import71 module. Import71 comes with ArcView. For non ArcView users, Import71 can be downloaded from a number of sources on the internet including:
There are many other comprehensive on-line tutorials for first time users of Import71 giving step by step instructions with screen shots. An internet search will quickly point you in the right direction. To save you time here are few links:
|GIS Library at MIT||http://libraries.mit.edu/gis/teach/howe00import71.html|
Data on MSDIS are provided in several other formats for specific applications. For example, imagery (raster) data in GeoTIF format or MrSID format, Census 2000 maps in Adobe Portable Document Format, NRCS soils maps in Shapefile format. Free viewers are available for most of these formats but will still need GIS software to make full use of them. The following table provides a quick summary:
|Other Data Types|
|File Extension||File Type||Example Data Type|
|Census 2000 official tract & voting district outline maps|
MrSid Georeference File
|DOQQ County Mosaics
& National Agricultural Imagery Program
| Tagged Image File Format
USGS Metadata Document File
TIFF Georeference File
ArcView Lookup File
DBase IV index
|Flood Insurance Maps|
|ArcView Spatial Index
ArcView Shapefile Index
Extensible Markup Language
ArcView Shapefile (Points)
|Missouri DNR Geology / Hydrology|
|Microsoft Acess Database
ArcView Shapefile (Points)
|NRCS Soils Data Viewer|
Most data on MSDIS are projected in the UTM (Universal Transverse Mercator). This system is a specialized application of the transverse Mercator projection which is both cylindrical and conformal. It divides the world into 60 numbered zones, both north and south, separated by the equator. Each zone spans six degrees of longitude and has its own central meridian. This system was adopted by the US Army Map Service in 1947 for their use in worldwide mapping and continues to be used worldwide. Most of Missouri falls into UTM zone 15 but part or all of 8 counties in the boot heel area of the state fall in Zone 16.
Some MSDIS data are provided in stateplane. The State Plane coordinate system is not a projection. It is a coordinate system that divides all fifty of the United States, Puerto Rico and the US Virgin Islands into over 120 numbered zones. Construction of a coordinate system for each zone is based on one of three projections: the Lambert Conformal Conic, the Transverse Mercator or the Oblique Mercator. The plane coordinate system used in Kansas is based on the Lambert Conformal Conic projection with two standard parallels for each zone--North and South. Each zone has an assigned USGS code, each having a designated central origin that is specified in degrees. Generally used on 7.5 and 15-minute topographic quadrangles.
There are two phases of the North American Datum - NAD27 and NAD83 - one local the other geocentric. Most data on MSDIS is NAD83. Local datum align a spheroid to closely fit the earth's surface in a particular area. A point on the surface of the spheroid is matched to a point on the earth's surface - this point is the origin of the datum and has fixed coordinates. All other points are calculated from the origin. The North American Datum of 1927 is a local datum based on the Clarke 1866 spheroid and centered on an area named "Meades Ranch" in Kansas.
Geocentric datum relate coordinates to the earth's center of mass. Such datum have been improved by modern satellite data. The North American Datum of 1983 is based on the modern GRS 1980 ellipsoid - almost identical to the most widely used WGS 1984 ellipsoid which is also geocentric. Both earth and satellite data went into the determination of this datum. Because raw GPS data is based on the WGS 1984 ellipsoid, the data is also compatible with NAD83.
Metadata are included in the files you can download from MSDIS. XML format is discoverable via the Data Search Tool. HTML format is accessible from links via the Dataset Listing Page.