This extension adds a coordinate transformation matrix and other metadata to allow transformation of pdf coordinates to a projected cartesian coordinate system. Gis glossary of terms a b c d e f g h i j k l m n o p q r. The terms geographic coordinate system and datum are used interchangeably, but as noted above, a gcs includes a datum, spheroid, units of measure and a prime meridian. Each page has detailed information on the individual gis data layers that are stored on the city of cambridge gis system. In this way, datums act similar to starting points when you give someone directions. The borough does not provide reprojection services. Gis data synonyms, gis data pronunciation, gis data translation, english dictionary definition of gis data.
In surveying and geodesy, a datum is a set of reference points on the earths surface against which position measurements are made, and often an associated model of the shape of the earth reference ellipsoid to define a geographic coordinate system. There is an assumption that up to 80% of all activities is linked to location. Statistics are related to territory and it means that they could be linked to a specific location. Gis glossary of terms abcdefghijklmnopqrstu vwxyza. A gis geographic information system is a powerful tool used for computerized mapping and spatial analysis. Gis data definition of gis data by the free dictionary. For instance, when you want to tell someone how to get to your house, you give them a. For the juno, the gps settings are displayed at the bottom, with. An arcinfo interchange format used to transfer coverages, grids and tins between.
Depending on equipment and procedures, this network can provide users the ability to achieve centimeter positioning for surveying applications or submeter positioning for gis mapping. Data dictionary nys streets nys gis program office document description this document contains the attribute field names and descriptions for the nys gis program offices nys streets layer. Examples include the north american datum of 1927 and the australian geodetic datum of 1966. Arcinfo is the top tier of the arcgis product suite. Handbook on geographic information systems and digital mapping. Some map projection parameters, such as the central meridian and standard parallel, are defined in angular units. Arcpad 6 the datum transformation shift wgs84 versus nad27. Gis dictionary geospatial definition glossary gis geography. A type of market analysis primarily used to look at competing sites or to select potential new locations. Naturally, there needs to exist consistent and standard regional or global reference frames.
Ether, the native ethereum protocol account unit may itself lose value in a. For a more complete description of the system and of each layer see the full data dictionary document. Why geography matters 8 gis helps answer such questions by combining data from governments and other sources in a custom map. Books from esri press are available to resellers worldwide through independent publishers group. The global positioning system uses the world geodetic system wgs84 as its reference coordinate system. Handbook on geographic information systems and digital. The scale is arbitrarily defined, such as from 1 to 10 by ones, 1 to 100 by 0. The coordinates for data change depending on the datum and spheroid on which those coordinates are based, even if they are using the same map projection and parameters.
Gis data dictionary the gis database dictionary is an online guide for our gis user community. For example, maps in the united states are often based on the north american datum of 1927 nad27 or 1983 nad83. A geodetic datum plural datums, not data is a reference from which spatial measurements are made. Cartographic and gis technical note glossary of common gis and gps terms a almanac. Gis a computer application used to store, view, and analyze geographical and statistical information. The esri press dictionary of gis terminology isbn 1879102781 first printing december 2000 printed in the united states of america. Nad83 datum north american datum, 1983 same as wgs84. Published by environmental systems research institute, inc.
Guide to trimble geoxh gps with terrasync the geoxh provides submeter accuracy after postprocessing, and can be configured to. A particular spheroid can be selected for use in a specific geographic area, because that particular spheroid does an exceptionally good job of mimicking the geoid for that part of the world. A datum is a model of the earth that is used in mapping. In a gis, attribute tables are often joined or related to spatial data layers, and the attribute values they contain can be used to find, query, and symbolize features or raster cells. In vector data, the basic units of spatial information are points, lines arcs and polygons. In a gis, a data dictionary might contain the full names of attributes, meanings of. Datum definition is something given or admitted especially as a basis for reasoning or inference.
It comprises of a reference ellipsoid, a standard coordinate system, altitude data and a geoid. A geodetic datum or geodetic system is a coordinate system, and a set of reference points, used to locate places on the earth or similar objects a geodetic datum is a tool used to define the shape and size of the earth, as well as the reference point for the various coordinate systems used in mapping the earth. Appendix a includes a list of valid field domains and additional descriptive information for field names in bold. All of them are correct, it just depends on whatever is appropriate for your area. All gps coordinates are based on the wgs84 datum surface. It will help you understand what content is required to deploy the maps and apps included in arcgis solutions for local government and how you can configure the information model to meet specific needs in your organization. Datum nad83 longitude longitude value of the wells coordinate. Datum definition, a single piece of information, as a fact, statistic, or code. In addition, many commercial gis software packages include reprojection tools. Geopdf is a published extension ogc 089r1 to the adobe pdf file format, from terrago technologies. A web service of the address point file of buildings and properties in new york state.
Use this parameter to apply one or more datum transformations to the map when sr is different than the map services spatial reference. In a gis, a data dictionary might contain the full names of attributes, meanings of codes, scale of source data, accuracy of locations, and map projections used. There are basically three classes of gps receivers. A gis provides functionality to capture, store, query, analyze, display and output geographic information. Continuously operating reference stations cors network. Nad27 datum north american datum, 1927 same as clarke 1866. Examples are the world geodetic system of 1984, the north american datum of 1983, and the geodetic datum of australia of 1994. Data dictionary to record attributes in greater detail. Datum a set of parameters and control points used to accurately define the threedimensional shape of the earth e. For north america, the spheroid of choice is grs 1980, on which the north american datum 1983 nad83 is.
Datum transformation a datum transformation is a mathematical calculation that converts the coordinates of a position in one datum to coordinates in terms of another datum. Nonspatial information about a geographic feature in a gis, usually stored in a table and linked to the. The layers described are created, edited and stored in esris geodatabase format but have been converted to more common formats for public use. This dictionary provides basic downloads and descriptions of the map features data layers in newtons gis database. Throughout time, hundreds of different datums have been used each one. The elevation above a reference datum, usually sea level, of any point on the earths surface or in the atmosphere. A method of manual data classification that seeks to partition data into classes based on. University lands oil and gas well data dictionary field name field definition api unique, permanent numeric identifier assigned to the well by the rrc latitude latitude value of the wells coordinate. A vectorbased geographic information system gis developed and marketed by esri, inc.
Therefore, any malfunction, unplanned function or unexpected operation of the ethereum protocol may cause the datum network or dats to malfunction or operate in a way that is not expected. The gis dictionary contains definitions of gis, cartography, remote sensing, and geographic terms. Similar to the north american datum of 1983 nad83, it. A horizontal geodetic datum based on an ellipsoid that has its origin at the earths center of mass. Vertical datum short integer this code represents the vertical datum of source dem. Please see example workflow here for a fictional case. Nysnet is a spatial reference network of continuously operating global positioning system gps reference stations cors throughout new york state that can be used for differential gps applications. Introduction to gis workbook university of maryland. A local datum in this sense stands in contrast to a geocentric datum. A data dictionary is used to catalog and communicate the structure and content of data, and provides meaningful descriptions for individually named data objects.
Download the data to your computer, and remove it from the gps. Most of the human activities are linked directly or indirectly to location. For this seminar we will be using arcgis desktop 10, the newest version of a popular gis software produced by esri. An approximate definition of sea level is the datum wgs 84, an ellipsoid, whereas a more accurate definition is earth gravitational model 2008 egm2008, using at least 2,159. The geographic approach benefits organizations of all sizes and in almost every industry, and there is a growing interest in and awareness of its economic and strategic value. Crossreferenceslisted after the last definition in an entry with see also, these terms are related in some way to the headword. Geographic concepts are defined here and are arranged alphabetically. The corresponding datum is the basis for a planar coordinate system datum a datum in general is a reference point, surface, or baseline from which measurements are made. Gis data dictionary gis city of cambridge, massachusetts. Chapter 2 gps data collection and delivery standards 2. Datums, coordinate systems, coordinate reference systems.
In an active network, users may list a networks datum points in the survey explorer. Address points are scale triggered and will turn on at 1. A coordinate system is usually defined by a map projection, a spheroid of reference, a datum, one or more standard parallels, a central meridian, and possible. Datums, coordinate systems, coordinate reference systems and datum transformations dean c. The zvalue in a threedimensional coordinate system. The second chapter discusses, inter alia, costbenefit analysis of an investment in digital cartography and gis, plans for census cartographic process, digital map database development, quality assurance, database maintenance, and use of gis during census enumeration. Yes it is very much possible to create a new datum in arcgis, and then create a 7p transformation to convert tofrom that datum. There are many types of datums, but most fall into two categories. In the coordinate system tab select newgeographic coordinate system. The datum consists of a series of numbers that define the shape and size of the ellipsoid and its orientation in space. Coordinate feet, alaska zone 4, using the north american datum of 1983.
If you are working with data dictionary information within formal. Data dictionary local government information model. Amfm automated mappingfacilities management automated cartography or geographic information systems gis used by utilities and public works organizations for storing. If you are in need of a different data projection, there are a variety of consultants available to undertake this task. Vector representation vector representation of data in the vector based model figure 4, geospatial data is represented in the form of coordinates. The data dictionary includes a description of the contents, format, and structure of the local government information model and the relationship between its elements. A video digitizer can be used in place of a manual digitizer, but since it.
823 102 78 106 1267 1177 1453 616 308 815 334 919 881 225 1153 845 508 702 599 1478 1104 741 1489 136 103 945 162 332 413