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Laws. Project. CAD. Networks. GRASS GIS - The World Leading Free Software GIS. THREADS - ESRI Discussion Forums. ArcWeb Services - Address Finder -Reverse Geocoding. SPC UTILITIES. The State Plane Coordinate system provides coordinates on a flat grid for easy computation while maintaining a difference between geodetic and grid distance of one part in 10,000 or better. The State Plane Coordinate system divides the U.S. into a hundred or more distinct grid surfaces (Zones). Do not mix coordinates from one Zone with that in another. In you need to cross Zone boundaries, use Geodetic Positions. The utilities in this package provide methods for converting between Geodetic Positions and State Plane Coordinates or for finding an SPC Zone.

For more information about the State Plane Coordinate System contact: The National Geodetic Survey Information Services Branch phone: (301) 713-3242; Fax:(301) 713-4172 [Mon. Download SPCS83 See the text version of an article about computing State Plane Coordinates that appeared in the Professional Surveyor magazine, January 2004 Volume 24, Number 1. Update 6: ESRI Invites Support for GIS for the Nation as Part of. Update 2/9/09: John Palatiello shared this proposal with National Geospatial Advisory Committee (NGAC) last week. Do read the author’s note that explains this proposal has not been submitted to anyone, nor does it have any endorsements. You can learn more about the NGAC meeting in tomorrow’s podcast. —- update 2/2/09————- Update 2/2/09: ESRI has added a “comments” e-mail address to its Building a National GIS website. You can submit comments to: gisnation@esri.com. ——- update 1/28/09———— Update 1/28: COGO shared its letter of Jan 26 to Senator Harry Reid regarding the “National Geospatial Infrastructure & Economic Recovery.”

There is no mention of any specific proposal. COGO’s most recent action related to Congress was a letter requesting House and Senate committees be assigned oversight of geospatial activities in the federal government (press release). ——- Update 1/23/09——— ——- Update 1/21/09———- Also, on Monday, 1/19, NSGIC president sent its endorsement letter to five Congresspersons. The Carbon Portal :: Open-Geospatial .NET Community. , Digital Elevation Data and Gis. Robert De Sawal U.S.GeologicalSurvey Denver,Colorado 80225 fax 303-202-4504 e-mail rfdesawal@usgs.gov The U.S. Photogrammetric Methods Digital ground elevation data is predominantly collected photogrammetrically, from stereo aerial photography, stereo satellite imagery, global positioning systems, ground surveying, and from scanned contour data vectorized as x,y,z point data.

One photogrammetric instrument, the Gestalt Photo Mapper 2 (GPM 2), was used by the U.S. Depicts the USGeoData, Data Users Guides that provide information about Digital Line Graph and DEM data stored in the NDCDB. Another photogrammetric method of elevation production is the collection of elevation data by profiling directly from stereo aerial photography.

And Figure 3 both show how this process is accomplished. Shows what the photogrammetric profiling tracks look like in relation to the 1:24,000-scale topographic map, (1mm=78.74 feet). Demonstrates how a portion of a stereomodel was collected using this methodology. U.S. John H. Porter. Working with Coordinate Systems. The great thing about geographic information systems is that data from different sources can be juxtaposed, according to the way that each is related to the suface of the planet -- and new information emerges about possible realtionships. This is made possible by spatial referencing systems such as Latitude and Longitude or projected coordinate systems. Software is getting better at aligning images and layers that are referenced in different coordinate systems, nevertheless we often encounter problems getting layers to line up as they should.

This document provides some tips for troubleshooting and fixing alignment problems with spatial data. Topics Covered in this Document Related Documents Aligning GIS Data Layers in ArcGIS GIS databases organize information about observations with information about location. Assessing a Non-alignment Problem Most of the time ArcMap is able to load different layers and to project them apropriately. Inspect Layer Properties Identifying a Coordinate System. Technical Articles - ESRI Support. GIS Cookbook: Recipe - Joining a table. Keywords: Tables, joining, relates, sorting, data analysisCategory: Data AnalysisSoftware: ArcGIS 8/9.x Problem: I have information in a table that I would like to join to a point, polygon or line layer.

Description: Often times, the information you want to display or analyze within GIS is in two different places or formats. Often you will have a map of a standard area, like the counties in a state or the states of a country, and you will want to add external data to them so you can look at that external data in a spatial context.

In this recipe we will look at how to join data to a shapefile. Scenario: Ever since the work of John Snow and his mapping of Cholera cases, mapping cases and frequencies of diseases can help to find sources and cures. One of the major research topics of the 20th century is the search for an understanding of cancer. It helps researchers in the subject to know where the cases of cancer are the highest. Methodology:1) Open ArcMap. Mapping and Modeling Tutorials.