A

AccuracyThe degree to which a measured value conforms to true or accepted values. Accuracy is a measure of correctness. It is distinguished from precision, which measures exactness. (ESRI)

Active LayerThe Active Layer is the data set that the application searches when you select an area of the map for detailed information. To make a layer active, check the round radio button to the left of the layer name in the Table of Contents.

AIRNowAIRNow is a cross-agency, government-backed program to report conditions to the public for ozone and particle pollution. Their Web site, airnow.gov, has maps and health-related information, publications in English y en español, and resources.

Air Quality

Air Quality Index (AQI)According to the AIRNow Air Quality Index (AQI) Web site (AIRNow AQI), "The AQI is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air. EPA calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. For each of these pollutants, EPA has established national air quality standards to protect public health. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in this country."  The AQI has values ranging from 0, for good air quality and low levels of health concern, to 500, for hazardous air quality and high levels of health concern.

AltitudeThe height or vertical elevation of a point above a reference surface. Altitude measurements are usually based on a given reference datum, such as mean sea level. (ESRI) See Elevation.

AQI (Air Quality Index)According to the AIRNow AQI (Air Quality Index) Web site (AIRNow AQI), "The AQI is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The AQI focuses on health effects you may experience within a few hours or days after breathing polluted air. EPA calculates the AQI for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. For each of these pollutants, EPA has established national air quality standards to protect public health. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in this country."  The AQI has values ranging from 0, for good air quality and low levels of health concern, to 500, for hazardous air quality and high levels of health concern.

AspectThe compass direction that a topographic slope faces, usually measured in degrees from north. Aspect can be generated from continuous elevation surfaces. For example, the aspect recorded for a TIN face is the steepest downslope direction of the face, and the aspect of a cell in a raster is the steepest downslope direction of a plane defined by the cell and its eight surrounding neighbors. (ESRI)

AttributeNonspatial information about a geographic feature in a GIS, usually stored in a table and linked to the feature by a unique identifier. For example, attributes of a river might include its name, length, and sediment load at a gauging station. (ESRI)

Attribute DataTabular or textual data describing the geographic characteristics of features. (ESRI)

Attribute TableA database or tabular file containing information about a set of geographic features, usually arranged so that each row represents a feature and each column represents one feature attribute. In raster data sets, each row of an attribute table corresponds to a certain zone of cells having the same value. 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. (ESRI)

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Background Layer

Base Map, BasemapA map depicting background reference information such as landforms, roads, landmarks, and political boundaries, onto which other, thematic information is placed. A basemap is used for locational reference and often includes a geodetic control network as part of its structure. (ESRI) The NM Tracking Application Base Map shows New Mexico and county boundaries, major roads, and cities and towns.

BiomonitoringThe assessment of exposure through direct measurement of environmental chemicals in human specimens, such as blood or urine. (CDC EPHT)

BoundaryA line separating adjacent political entities, such as countries or districts; adjacent tracts of privately-owned land, such as parcels; or adjacent geographic zones, such as ecosystems. A boundary is a line that may or may not follow physical features, such as rivers, mountains, or walls. (ESRI)

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Cardinal PointOne of the four compass directions on the Earth's surface: north, south, east, or west. (ESRI)

CDCCenters for Disease Control and Prevention

Census BlockThe smallest geographic entity for which the U.S. Census Bureau tabulates decennial census data. Many blocks correspond to city blocks bounded by streets, but blocks in rural areas may include several square miles and have some boundaries that are not streets. The Census Bureau established blocks covering the entire nation for the first time in 1990. Previous censuses dating back to 1940 had blocks established only for part of the nation. (ESRI)

Census Block GroupA unit of U.S. census geography that is a combination of census blocks. A block group is the smallest unit for which the U.S. Census Bureau reports a full range of demographic statistics. There are about 700 residents per block group. A block group is a subdivision of a census tract. (ESRI)

Census GeographyAny one of various types of precisely defined geographic areas used by the U.S. Census Bureau to collect and aggregate data. The largest unit of area is the entire United States, while the smallest is a census block. (ESRI)

Census TractA small, statistical subdivision of a county that usually includes approximately 4,000 inhabitants, but which may include from 2,500 to 8,000 inhabitants. A census tract is designed to encompass a population with relatively uniform economic status, living conditions, and some demographic characteristics. Tract boundaries normally follow physical features, but may also follow administrative boundaries or other non-physical features. A census tract is a combination of census block groups. (ESRI)

Centers for Disease Control and Prevention (CDC)

Choropleth MapA thematic map in which areas are distinctly colored or shaded to represent classed values of a particular phenomenon. (ESRI)

ClassificationThe process of sorting or arranging entities into groups or categories; on a map, the process of representing members of a group by the same symbol, usually defined in a legend. (ESRI)

Column1) An item in an attribute table. 2) The vertical dimension of a table. Each column stores the values of one type of attribute for all the records, or rows, in the table. All the values in a given column are of the same data type; for example, number, string, or date. (ESRI)

Continuous DataData, such as elevation or temperature, that vary without discrete steps. Since computers store data discretely, continuous data are usually represented by TINs, rasters, or contour lines, so that any location has either a specified value or one that can be derived. (ESRI)

CoordinatesA set of values represented by the letters x, y, and optionally z or m (measure), that define a position within a spatial reference. Coordinates are used to represent locations in space relative to other locations. (ESRI) The NM Tracking Application x-coordinate is represented by Northing, or longitude, and the y-coordinate is represented by Easting, or latitude.

CountyThe primary legal subdivision of all U.S. states except Alaska and Louisiana. The U.S. Census Bureau uses counties or equivalent entities (boroughs in Alaska, parishes in Louisiana, the District of Columbia in its entirety, and municipios in Puerto Rico) as statistical subdivisions. (ESRI)

Cultural FeatureA human-made feature represented on a map, such as a road or airport. (ESRI)

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Data (also, Data Set)Any collection of related facts arranged in a particular format; often, the basic elements of information that are produced, stored, or processed by a computer. (ESRI)

DatabaseOne or more structured sets of persistent data, managed and stored as a unit and generally associated with software to update and query the data. A simple database might be a single file with many records, each of which references the same set of fields. A GIS database includes data about the spatial locations and shapes of geographic features recorded as points, lines, areas, pixels, or grid cells, as well as their attributes. (ESRI)

Data LayerA Data Layer is a data set that contains spatial information so that it is enabled for mapping.

DatumThe reference specifications of a measurement system, usually a system of coordinate positions on a surface (a horizontal datum) or heights above or below a surface (a vertical datum). (ESRI) NM Tracking Application data sets are displayed with World Geodetic System of 1984 (WGS84) Datum.

Degree1) A unit of angular measure represented by the symbol . The earth is divided into 360 degrees of longitude and 180 degrees of latitude. 2) The angle equal to 1/360th of the circumference of a circle. A degree can be divided into 60 minutes of arc or 3600 seconds of arc. (ESRI) degrees/minutes/seconds – The unit of measure for describing latitude and longitude. A degree is 1/360th of a circle. A degree is further divided into 60 minutes, and a minute is divided into 60 seconds. (ESRI)

DEMDigital Elevation Model

Digital Elevation Model (DEM)

Discrete DataData that represent phenomena with distinct boundaries. Property lines and streets are examples of discrete data. (ESRI)

DistanceThe measure of separation between two entities or locations that may or may not be connected, such as two points. Distance is differentiated from length, which implies a physical connection between entities or locations. (ESRI)

Domain

Drag [a box with the mouse button]Click on the map and keep the left mouse button depressed while you draw a box over the area of interest. Release the mouse button to set the box location. The NM Tracking Application Zoom In tool and Map Extent box allow you to drag a box on the map or map extent.

DREAM, DReAMDust Regional Atmospheric Model. DREAM is the Dust REgional Atmospheric Model that has been developed, using air quality and weather data, to forecast amounts of dust in the air we breathe. The mapping application is based on DREAM data outputs for the southwestern United States, including Nevada and southern California east to Nebraska and much of Texas. DREAM is an integrated atmospheric and dust concentration modeling system initially developed for the Mediterranean region by Dr. Slobodan Nickovic. NASA has funded the development of DREAM and the mapping application for the southwestern U.S. at the University of Arizona and the University of New Mexico's Earth Data Analysis Center.

DREAM DomainThe DREAM Domain is the area covered by the model results; it extends across the southwestern United States, including Nevada and southern California east to Nebraska and much of Texas.

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EDACEarth Data Analysis Center. Earth Data Analysis Center ... at the University of New Mexico.

ElevationThe vertical distance of a point or object above or below a reference surface or datum (generally, mean sea level). Elevation generally refers to the vertical height of land. (ESRI)

Environmental Protection Agency (EPA)http://www.epa.gov/

Environmental Public Health Tracking (EPHT)....

EPAU.S. Environmental Protection Agency. http://www.epa.gov/

EPHTEnvironmental Public Health Tracking.

ExtentThe minimum bounding rectangle (xmin, ymin and xmax, ymax) defined by coordinate pairs of a data source. All coordinates for the data source fall within this boundary. (ESRI) See Map Extent.

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FeatureA representation of a real-world object on a map. (ESRI)

Line FeatureA map feature that has length but not area at a given scale, such as a river on a world map or a street on a city map. (ESRI)

Point FeatureA map feature that has neither length nor area at a given scale, such as a city on a world map or a building on a city map. (ESRI)

Polygon FeatureA map feature that bounds an area at a given scale, such as a country on a world map or a district on a city map. (ESRI)

Full Extent, Full ViewThe limit of the geographic area shown on a map. The NM Tracking Application Full Extent or Full View is a map that shows New Mexico. Click on the Full Extent button and the map will change to the full New Mexico map, showing the same data layers that were displayed on the zoomed-in map.

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Geographic CoordinateA measurement of a location on the Earth's surface expressed in degrees of latitude and longitude. (ESRI)

Geographic DataInformation describing the location and attributes of things, including their shapes and representation. Geographic data are the composite of spatial data and attribute data. (ESRI)

Geographic Information System, GISAn integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes. A GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed. (ESRI)

GeographyThe study of the Earth's surface, encompassing the description and distribution of the various physical, biological, economic, and cultural features found on the Earth and the interaction between those features. (ESRI)

GeometryThe measures and properties of points, lines, and surfaces. In a GIS, geometry is used to represent the spatial component of geographic features. (ESRI)

GIS, Geographic Information SystemAn integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes. A GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed. (ESRI)

GridIn cartography, any network of parallel and perpendicular lines superimposed on a map and used for reference. These grids are usually referred to by the map projection or coordinate system they represent, such as universal transverse Mercator grid. (ESRI)

GTOPO30GTOPO30 is a global digital elevation model (DEM) that provides the first global coverage of moderate-resolution elevation data, from 90°S to 90°N and 180°W to 180°E. The name GTOPO30 is derived from the fact that elevations in GTOPO30 are regularly spaced in a horizontal grid of 30-arc seconds (approximately 1 kilometer). Vertical elevation is measured in meters above mean sea level. This data set results from a collaborative effort led by the staff at the U.S. Geological Survey's EROS Data Center in Sioux Falls, South Dakota, and involving the National Aeronautics and Space Administration (NASA), the United Nations Environment Programme Global Resource Information Database (UNEP/GRID), the U.S. Agency for International Development (USAID), the Instituto Nacional de Estadística Geografía e Informática (INEGI) of Mexico, the Geographical Survey Institute (GSI) of Japan, Manaaki Whenua Landcare Research of New Zealand, and the Scientific Committee on Antarctic Research (SCAR). GTOPO30 information from the U.S. Geological Survey (USGS) can be found at www.nwrc.usgs.gov/world/content/people5.html, rockyweb.cr.usgs.gov/outreach/gtopo30.html, and webgis.wr.usgs.gov/globalgis/gtopo30/gtopo30.htm.

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H

Health Policy Commission, HPCNew Mexico Health Policy Commission. HPC provides independent research, guidance, and recommendations on health policy issues that impact New Mexicans. http://www.hpc.state.nm.us/

Horizontal Geodetic DatumA geodetic datum for any extensive measurement system of positions, usually expressed as latitude-longitude coordinates, on the Earth's surface. A horizontal geodetic datum may be local or geocentric. If it is local, it specifies the shape and size of an ellipsoid representing the Earth, the location of an origin point on the ellipsoid surface, and the orientation of x- and y-axes relative to the ellipsoid. If it is geocentric, it specifies the shape and size of an ellipsoid, the location of an origin point at the intersection of x-,y-, and z-axes at the center of the ellipsoid, and the orientation of the x-,y-, and z-axes relative to the ellipsoid. Examples of local horizontal geodetic datums include the North American Datum of 1927, the European Datum of 1950, and the Indian datum of 1960; examples of geocentric horizontal geodetic datums include the North American Datum of 1983 and the World Geodetic System of 1984 (WGS84). (ESRI) The NM Tracking Application displays data sets with the World Geodetic System of 1984.

HPC, Health Policy CommissionNew Mexico Health Policy Commission. HPC provides independent research, guidance, and recommendations on health policy issues that impact New Mexicans. http://www.hpc.state.nm.us/

hrhour(s)

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K

kilometer, kmone thousand meters.

kmkilometer; one thousand meters.

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LatitudeThe angular distance, usually measured in degrees north or south of the Equator. Lines of latitude are also referred to as parallels. (ESRI)

Latitude-LongitudeA reference system used to locate positions on the Earth's surface. Distances east-west are measured with lines of longitude (also called meridians), which run north-south and converge at the North and South Poles. East-west distance measurements begin at the Prime Meridian, and are measured positively 180 degrees to the east and negatively 180 degrees to the west. Distances north-south are measured with lines of latitude (also called parallels) which run east-west. North-south distance measurements begin at the Equator and are measured positively 90 degrees to the north and negatively 90 degrees to the south. (ESRI)

LayerThe visual representation of a geographic data set in any digital map environment. Conceptually, a layer is a slice or stratum of the geographic reality in a particular area, and is more or less equivalent to a legend item on a paper map. On a road map, for example, roads, national parks, political boundaries, and rivers might be considered different layers. (ESRI) Also, a data Layer is a data set that contains spatial information so that it is enabled for mapping. 'To Layer' means to map and explore more than one data set concurrently.

LegendThe Legend contains the colors, symbols, and names that describe or represent each data set, or data layer, that is mapped.

LineOn a map, a shape defined by a connected series of unique x,y coordinate pairs. A line may be straight or curved. (ESRI)

Location1) An identifier assigned to a region or feature. 2) A position defined by a coordinate value. (ESRI)

LongitudeThe angular distance, usually expressed in degrees, minutes, and seconds, of the location of a point on the Earth's surface east or west of an arbitrarily defined meridian (usually the Greenwich Prime Meridian). All lines of longitude are great circles that intersect the Equator and pass through the North and South Poles. (ESRI)

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M

mmeter(s). Unit of length in the International System of Units, equal to 39.37 inches.
m∗∗3meter(s) cubed.

Map1) A graphic representation of the spatial relationships of entities within an area. 2) Any graphical representation of geographic or spatial information. 3) The document used to display and work with geographic data. A map contains one or more layers of geographic data and various supporting map elements, such as a scale bar. (ESRI)

Map AreaThe Map Area is surrounded on four sides by the Map Frame and is the place where data sets, or map layers, are drawn to create the map view.

Map ElementIn digital cartography, a distinctly identifiable graphic or object in the map or page layout. For example, a map element can be a title, scale bar, legend, or other map-surround element. The map area itself can be considered a map element; or an object within the map can be referred to as a map element, such as a roads layer or a school symbol. (ESRI)

Map ExtentThe limit of the geographic area shown on a map, usually defined by a rectangle. In a dynamic map display, the map extent can be changed by zooming and panning. (ESRI)

Map FrameThe Map Frame surrounds the Map Area as four grey strips. It also contains directional pan arrows that move the map in the direction of the clicked arrow.

mcg, ug, μgmicrogram(s); one one-millionth of a gram.

MeasurementAn observed numerical value that is an appraisal of size, extent, or amount according to a set of criteria. (ESRI)

meterUnit of length in the International System of Units, equal to 39.37 inches.

micrometerone one-millionth of a meter; sometimes called a micron.

msmillisecond(s); one one-thousandth of a second.

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N

NASA, N.A.S.A.U.S. National Aeronautics and Space Administration. http://www.nasa.gov/

NMNew Mexico.

NMDOH or NM DOHNew Mexico Department of Health. http://www.health.state.nm.us/

NMDOH EHEBEnvironmental Health Epidemiology Bureau, a bureau within the NM Department of Health and the New Mexico EPHT Grantee. http://www.health.state.nm.us/eheb/

NMEDNew Mexico Environment Department. http://www.nmenv.state.nm.us/

NMED AQBNM Environment Department Air Quality Bureau. http://www.nmenv.state.nm.us/aqb/

NMED DWBNM Environment Department Drinking Water Bureau. http://www.nmenv.state.nm.us/dwb/

NM HPC, NM Health Policy CommissionNew Mexico Health Policy Commission. HPC provides independent research, guidance, and recommendations on health policy issues that impact New Mexicans. http://www.hpc.state.nm.us/

Nominal DataData divided into classes within which all elements are assumed to be equal to each other, and in which no class comes before another in sequence or importance; for example, a group of polygons colored to represent different soil types. (ESRI)

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Ordinal DataData classified by comparative value; for example, a group of polygons colored lighter to darker to represent less to more densely populated areas. (ESRI)

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PanTo shift a map image relative to the display window without changing the viewing scale. (ESRI)

Pan – DirectionalClick on an arrow in the frame around the map and the map will shift in that direction. The map will move up an area equal to half of the visible map. The Directional Pan arrows are for north, northeast, east, southeast, south, southwest, west, and northwest.

Particulate Matter (PM)Particles suspended in breathing-level air. (Text for PM, PM2.5, and PM10 is from the AIRNow Web site at http://airnow.gov.) Particle pollution, also known as particulate matter, in the air includes a mixture of solids and liquid droplets. Some particles are emitted directly; others are formed in the atmosphere when other pollutants react. Particles come in a wide range of sizes. Those less than 10 micrometers in diameter (PM10) are so small that they can get into the lungs, potentially causing serious health problems. Ten micrometers is smaller than the width of a single human hair.
Particle exposure can lead to a variety of health effects. For example, numerous studies link particle levels to increased hospital admissions and emergency room visits—and even to death from heart or lung diseases. Both long- and short-term particle exposures have been linked to health problems. Long-term exposures, such as those experienced by people living for many years in areas with high particle levels, have been associated with problems such as reduced lung function and the development of chronic bronchitis and even premature death. Short-term exposures to particles (hours or days) can aggravate lung disease, causing asthma attacks and acute bronchitis, and may also increase susceptibility to respiratory infections. In people with heart disease, short-term exposures have been linked to heart attacks and arrhythmias. Healthy children and adults have not been reported to suffer serious effects from short-term exposures, although they may experience temporary minor irritation when particle levels are elevated.

PM2.5Fine particles are particles less than 2.5 micrometers in diameter. These particles are so small they can be detected only with an electron microscope. Sources of fine particles include all types of combustion, including motor vehicles, power plants, residential wood burning, forest fires, agricultural burning, and some industrial processes.

PM10Coarse dust particles are particles between 2.5 and 10 micrometers in diameter. Sources of coarse particles include crushing or grinding operations and dust stirred up by vehicles traveling on roads.

PDFAdobe Portable Document Format. The PDF file type is viewed with the Adobe Reader, a free download from http://www.adobe.com.

PHAiRSPublic Health Applications in Remote Sensing. http://phairs.unm.edu/ links to the project Web site. PHAiRS is discussed further under the DREAM glossary entry.

Pixel1) The smallest unit of information in an image or raster map, usually square or rectangular. Pixel is often used synonymously with cell. 2) In remote sensing, the fundamental unit of data collection. A pixel is represented in a remotely sensed image as a cell in an array of data values. 3) The smallest element of a display device, such as a video monitor, that can be independently assigned attributes, such as color and intensity. Pixel is an abbreviation for picture element. (ESRI)

PMParticulate Matter. (Text for PM, PM2.5, and PM10 is from the AIRNow Web site at http://airnow.gov.) Particle pollution, also known as particulate matter, in the air includes a mixture of solids and liquid droplets. Some particles are emitted directly; others are formed in the atmosphere when other pollutants react. Particles come in a wide range of sizes. Those less than 10 micrometers in diameter (PM10) are so small that they can get into the lungs, potentially causing serious health problems. Ten micrometers is smaller than the width of a single human hair.

PM2.5Fine particles are particles less than 2.5 micrometers in diameter. These particles are so small they can be detected only with an electron microscope. Sources of fine particles include all types of combustion, including motor vehicles, power plants, residential wood burning, forest fires, agricultural burning, and some industrial processes.

PM10Coarse dust particles are particles between 2.5 and 10 micrometers in diameter. Sources of coarse particles include crushing or grinding operations and dust stirred up by vehicles traveling on roads.

PointA geometric element defined by a pair of x,y coordinates. (ESRI) A point represents a feature's location but not its shape or how much area it covers. Examples of points on a map are individual buildings, monitoring stations, and towers.

PolygonOn a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique. (ESRI) Examples of polygons are rectangles, circles, ovals, the areas enclosed by the City Limits layer, the areas that represent classes or types of vegetation in the Vegetation layer, etc.

PositionThe latitude, longitude, and altitude (x,y,z coordinates) of a point, often accompanied by an estimate of error. Position may refer to an object's orientation (facing east, for example) without referring to its location. (ESRI)

Precision1) The closeness of a repeated set of observations of the same quantity to one another. Precision is a measure of the control over random error. For example, assessment of the quality of a surveyor's work is based in part on the precision of their measured values. 2) The number of significant digits used to store numbers, particularly coordinate values. Precision is important for accurate feature representation, analysis, and mapping. (ESRI)

ProjectionA method by which the curved surface of the Earth is portrayed on a flat surface. This generally requires a systematic mathematical transformation of the Earth's graticule of lines of longitude and latitude onto a plane. Some projections can be visualized as a transparent globe with a light bulb at its center (though not all projections emanate from the globe's center) casting lines of latitude and longitude onto a sheet of paper. Generally, the paper is either flat and placed tangent to the globe (a planar or azimuthal projection) or formed into a cone or cylinder and placed over the globe (cylindrical and conical projections). Every map projection distorts distance, area, shape, direction, or some combination thereof. (ESRI) NM Tracking Application Projection: Geographic, WGS84 Spheroid, WGS84 Datum.

PropertyAn attribute of an object defining one of its characteristics or an aspect of its behavior. (ESRI)

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RasterA spatial data model that defines space as an array of equally sized cells arranged in rows and columns, and composed of single or multiple bands. Each cell contains an attribute value and location coordinates. Unlike a vector structure, which stores coordinates explicitly, raster coordinates are contained in the ordering of the matrix. Groups of cells that share the same value represent the same type of geographic feature. (ESRI)

REASON

Record1) A set of related data fields, often a row in a database, containing all the attribute values for a single feature. For example, in an address database, the fields that together provide the address for a specific individual comprise one record. In the SQL query language, a record is analogous to a tuple. 2) A row in a table. (ESRI) A Record is synonymous with a row in a database or table; it contains information from all of the columns, or fields, for the item in that line.

Refresh MapWhen selecting or de-selecting data layers or an active layer in the Table of Contents/Legend box, you must click on Refresh Map to redraw the map with the new layers.

Relational DatabaseA data structure in which collections of tables are logically associated with each other by shared fields. (ESRI)

ReliefElevations and depressions of the Earth's surface, including those of the ocean floor. Relief can be represented on maps by contours, shading, hypsometric tints, digital terrain modeling, or spot elevations. (ESRI)

Resolution1) The detail with which a map depicts the location and shape of geographic features. The larger the map scale, the higher the possible resolution. As scale decreases, resolution diminishes and feature boundaries must be smoothed, simplified, or not shown at all; for example, small areas may have to be represented as points. 2) The dimensions represented by each cell or pixel in a raster. 3) The smallest spacing between two display elements, expressed as dots per inch, pixels per line, or lines per millimeter. (ESRI)

Row1) A record in a table. 2) The horizontal dimension of a table composed of a set of columns containing one data item each. 3) A horizontal group of cells in a raster, or pixels in an image. (ESRI)

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S

Safe Drinking Water Act, SDWAU.S. EPA Safe Drinking Water Act. http://www.epa.gov/safewater/sdwa/

Safe Drinking Water Information System, SDWISU.S. EPA Safe Drinking Water Information System. http://www.epa.gov/safewater/databases/sdwis/

ScaleThe ratio or relationship between a distance or area on a map and the corresponding distance or area on the ground, commonly expressed as a fraction or ratio. A map scale of 1/100,000 or 1:100,000 means that one unit of measure on the map equals 100,000 of the same unit on the Earth. (ESRI)

Scale Dependence

SDWA, Safe Drinking Water ActU.S. EPA Safe Drinking Water Act. http://www.epa.gov/safewater/sdwa/

SDWIS, Safe Drinking Water Information SystemU.S. EPA Safe Drinking Water Information System. http://www.epa.gov/safewater/databases/sdwis/

Select LayersAlso called Legend or Table of Contents (TOC). Selecting layers allows exploration of one or more data layers in the map. Click on the square box next to the data layer(s) of interest and then click Refresh Map to see a box on the right side of the map area.

Shaded Relief

ShapefileA vector data storage format for storing the location, shape, and attributes of geographic features. A shapefile is stored in a set of related files and contains one feature class. (ESRI)

SlopeThe incline, or steepness, of a surface. Slope can be measured in degrees from horizontal (090), or percent slope (which is the rise divided by the run, multiplied by 100). A slope of 45 degrees equals 100 percent slope. As slope angle approaches vertical (90 degrees), the percent slope approaches infinity. The slope of a TIN face is the steepest downhill slope of a plane defined by the face. The slope for a cell in a raster is the steepest slope of a plane defined by the cell and its eight surrounding neighbors. (ESRI)

Spatial Data1) Information about the locations and shapes of geographic features and the relationships between them, usually stored as coordinates and topology. 2) Any data that can be mapped. (ESRI)

SpheroidWhen used to represent the Earth, a three-dimensional shape obtained by rotating an ellipse about its minor axis, with dimensions that either approximate the Earth as a whole, or with a part that approximates the corresponding portion of the geoid. (ESRI) NM Tracking Application data sets are displayed with World Geodetic System of 1984 (WGS84) Spheroid.

SurfaceA geographic phenomenon represented as a set of continuous data (such as elevation, geological boundaries, or air pollution); a spatial distribution which associates a single value with each position in a plane, usually associated with continuous attributes. (ESRI)

SymbolA graphic used to represent a geographic feature or class of features. Symbols can look like what they represent (trees, railroads, houses), or they can be abstract shapes or characters. Symbols are usually explained in a map legend. (ESRI)

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TableA set of data elements arranged in rows and columns. Each row represents a single record. Each column represents a field of the record. Rows and columns intersect to form cells, which contain a specific value for one field in a record. A table stores attribute data. (ESRI)

Table of Contents (also called a Legend)The Table of Contents/Legend section lists the data layers that can be selected for mapping. Checking the square button to the left of the layer name and then clicking on Refresh Map results in a map of the selected layer(s).

Tabular DataDescriptive information, usually alphanumeric, that is stored in rows and columns in a database and can be linked to spatial data. (ESRI)

Temporal DataData that specifically refer to times or dates. Temporal data may refer to discrete events, such as dust storms or lightning strikes; moving objects, such as trains; or repeated observations, such as counts from traffic sensors. (ESRI)

TerrainAn area of land having a particular characteristic, such as sandy terrain or mountainous terrain. (ESRI)

TextureA digital representation of the surface of a feature. (ESRI)

Thematic DataFeatures of one type that are generally placed together in a single layer. (ESRI)

Thematic MapA map designed to convey information about a single topic or theme, such as population density or geology. (ESRI)

TIGERAcronym for Topologically Integrated Geographic Encoding and Referencing. The nationwide digital database developed for the 1990 Census, succeeding the DIME format. TIGER files contain street address ranges, census tracts, and block boundaries. (ESRI)

TINAcronym for Triangulated Irregular Network. A vector data structure that partitions geographic space into contiguous, non-overlapping triangles. The vertices of each triangle are sample data points with x-, y-, and z-values. These sample points are connected by lines to form Delaunay triangles. TINs are used to store and display surface models. (ESRI)

ToolA command that requires interaction with the user interface before an action is performed. For example, a zoom tool requires a user to use the mouse to click on or draw a box over a digital map before the tool will cause the map to be redrawn at a larger scale. (ESRI)

Topographic MapA map that represents the vertical and horizontal positions of features, showing relief in some measurable form, such as contour lines, hypsometric tints, and relief shading. (ESRI)

TopographyThe study and mapping of land surfaces, including relief (relative positions and elevations) and the position of natural and constructed features. (ESRI)

ToolA command that requires interaction with the user interface before an action is performed. For example, a zoom tool requires a user to use the mouse to click on or draw a box over a digital map before the tool will cause the map to be redrawn at a larger scale. (ESRI)

TopologyIn geodatabases, the arrangement that constrains how point, line, and polygon features share geometry. For example, street centerlines and census blocks share geometry, and adjacent soil polygons share geometry. Topology defines and enforces data integrity rules (for example, there should be no gaps between polygons). It supports topological relationship queries and navigation (for example, navigating feature adjacency or connectivity), supports sophisticated editing tools, and allows feature construction from unstructured geometry (for example, constructing polygons from lines). (ESRI)

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UVW

ug, μgmicrogram(s); one one-millionth of a gram.

UNMUniversity of New Mexico

U.S., U.S.A.United States of America

U.S. EPAUnited States Environmental Protection Agency. http://www.epa.gov/

User GuideThe User Guide includes information on the NM Tracking Tools application, how to use the mapping tools and buttons, information on the data sets, who to contact for more information, and a glossary of terms used in the application. Download the User Guide (PDF).

USGS, U.S.G.S.United States Geological Survey. http://www.usgs.gov/

VectorA coordinate-based data model that represents geographic features as points, lines, and polygons. Each point feature is represented as a single coordinate pair, while line and polygon features are represented as ordered lists of vertices. Attributes are associated with each vector feature, as opposed to a raster data model, which associates attributes with grid cells. (ESRI)

W3CWorld Wide Web Consortium.

WGS84World Geodetic System of 1984; a widely-used geocentric datum and geographic coordinate system, designed by the U.S. Department of Defense to replace WGS72. (excerpt from ESRI)

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XYZ

x,y CoordinatesA pair of values that represents the distance from an origin (0,0) along two axes, a horizontal axis (x), and a vertical axis (y). On a map, x,y coordinates are used to represent features at the location they are found on the Earth's spherical surface. (ESRI)

x,y,z CoordinatesIn a planar coordinate system, three coordinates that locate a point by its distance from an origin (0,0,0) where three orthogonal axes cross. Usually, the x-coordinate is measured along the east-west axis, the y-coordinate is measured along the north-south axis, and the z-coordinate measures height or elevation. (ESRI)

ZoomTo display a larger or smaller region of an on-screen map or image. (ESRI)

Zoom InIn the NM Tracking Application, click on the map and keep the left mouse button depressed while you drag a box over the area to magnify or zoom to. Release the mouse button and the map will re-draw to display the area in the box; the center of the box you draw will be the center of the map view. Or, you can click on the map location that you want to be the center point as the view changes to a larger scale that covers less area.

Zoom OutIn the NM Tracking Application, click on the map location that you want to be the center point as the view changes to a smaller scale that covers more area.

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