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The PHAiRS mapping application allows you to explore your community's environment using the data output from a regional dust forecasting model, DREAM.
You can map data that represent information on land surfaces, culture (including cities, political boundaries, roads, and airports), and air quality measures. And, you can search the air quality data layers for detailed information about specific dates and locations within the DREAM study area. You can also use browser functions to save a map page or to return to the previous map page. The browser window can be minimized, re-sized, and closed in the same manner as other Web browser windows. Right-click on Web links to select the option to open a site in a new tab or window; otherwise, the new site will replace the User Guide in this window.
Use your browser Favorites or Bookmarks setting to save map pages for later sessions.
Use the browser Back button to look at previous map pages.
Right-click on Web links to select the option to open the site in a new tab or window.
Do you want to open the PHAiRS Mapping Application? (Right-click on the link to select the new tab or window option.)
Please look through the descriptions for using the application and tools to start mapping!
This section describes the application components and how to use the mapping tools.
The initial PHAiRS Base Map displays a color Digital Elevation Model (DEM) for North America in the Map Area. The image below shows the initial PHAiRS application with labels for its different components.
The Map Area is enclosed by the Map Frame, four gray strips that contain Arrow buttons to Pan (move) the map through the North, East, South, and West directions. A Table of Contents and Legend box on the right-hand side allows you to check ‘on’ the data layers you wish to map. A clock symbol next to a data layer name indicates that the data set is time-sensitive. Click the Refresh Map or a Navigation button, or in the map area, to view your newly-selected layers. (Previous Extent, Full Extent, Zoom In, Zoom Out, and Directional Pan Arrows are Navigation tools.) Background Layers, below the data layers in the Legend, lets you select a color DEM or gray-scale Shaded Relief for the background map. You must click on Refresh Map, the map, or a Navigation button if you change the Background Layer. The Date and Time Settings options and Refresh Map button are in a gray box, below the Background Layers. Date and Time Settings allow you to specify a time of interest for the time-sensitive air quality data layers. Below that gray box, the Reference Map, or Location Map, shows a small version of the full map (North America) with a red outline to indicate the current map area.
Application buttons and tools are along the left-hand side of the map: Zoom In, Zoom Out, Full View, Previous View, Raster Density Function, and Time Series Analysis. The open-book button opens the User Guide in a new window. These are described in the Buttons and Tools section.
Below the map frame, starting on the left-hand side and moving right, are the Northing and Easting coordinates for the cursor position, an option to choose a Map Size (Small, Medium, or Large) for viewing in your browser window, and the Map Scale.
Under the mapping application box are seven logos that link to Web sites for information on the PHAiRS programming languages and services: MapServer, GRASS, R, PostgreSQL, PostGIS, W3C XHTML1.0 Validation, and W3C CSS Validation. Links and descriptions are given in the PHAiRS Project and Contact Information section.
back to how-to index Buttons and Tools Time Series Analysis Selecting Data Layers
Map FrameThe Map Frame is the gray strip around the four sides of the map. You will also see arrows in the Map Frame; click on an arrow to move the map in that direction. (See "Directional Pan" below for a description of the arrow functions.)
Zoom In"Magnify" Click on the Zoom In button and then on the map, keeping the 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 and the map will re-draw with the view changing to a larger scale that covers less area. The zoomed-in map view is two times larger than the view you clicked on.
Zoom OutClick on the Zoom Out button and then on the map location that you want to be the center point and the view will change to a smaller scale that covers more area. The zoomed-out map view covers two times more area than the map that you clicked on.
Full Viewalso called Full ExtentClick on this button to see the entire area that the map covers (North America); the map refreshes automatically when the button is clicked. The same data layers will be shown on the full map that were displayed on the zoomed-in map.
Previous Viewalso called Previous ExtentClick on this button to see the map view before your current one; the map refreshes automatically when the button is clicked. The same data layers will be shown on the previous map that were displayed on the map you just left.
Raster Density FunctionThe Raster Density function is under development for the next release of the PHAiRS mapping application.
Time Series AnalysisThe Time Series Analysis function allows you to set parameters for a 48-hour DREAM dust storm forecast. Click on this button and a box will open below the map application with options for particulate matter size, date, city or point of interest, and animation scale. A new window opens when the Analysis is run for the specified parameters; a 48-hour animated map displays the modeled dust forecast, while a graph indicates the predicted air quality for each of the 48 hours.
User GuideClick on the open-book link to view and read the PHAiRS User Guide in a new window. This on-line User Guide also has a link to download the Guide as an Adobe Portable Document Format (PDF) file. The User Guide includes information on the PHAiRS 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. The window can be minimized and closed in the same manner as other Web browser windows.
The following eight arrow buttons are on the map frame and allow directional pan.
Directional PanNorth, Northeast, East, Southeast, South, Southwest, West, Northwest
Pan NorthClick on the arrow in the top frame around the map and the map will shift in the north direction. The map will move up an area equal to half of the visible map.
Pan North-EastClick on the arrow in top right corner of the frame around the map and the map will shift in the northeast direction. The map will move up and right an area equal to half of the visible map.
Pan EastClick on the arrow in the right-hand frame around the map and the map will shift in the east direction. The map will move right an area equal to half of the visible map.
Pan South-EastClick on the arrow in bottom right corner of the frame around the map and the map will shift in the southeast direction. The map will move down and right an area equal to half of the visible map.
Pan SouthClick on the arrow in the bottom frame around the map and the map will shift in the south direction. The map will move down an area equal to half of the visible map.
Pan South-WestClick on the arrow in the bottom left corner of the frame around the map and the map will shift in the southwest direction. The map will move down and left an area equal to half of the visible map.
Pan WestClick on the arrow in the left-hand frame around the map and the map will shift in the west direction. The map will move left an area equal to half of the visible map.
Pan North-WestClick on the arrow in the top left corner of the frame around the map and the map will shift in the northwest direction. The map will move up and left an area equal to half of the visible map.
Selecting Data LayersThis image is an example of selecting data layers to be mapped by checking the white square box next to the layer(s) of interest. These data layers are listed under the heading Legend. The Legend is sometimes called the Table of Contents. Here, layers for Urban Areas and Water Bodies have been checked (selected for mapping). A clock symbol next to a data layer indicates that the data set is time-dependent. Selecting a time-dependent data layer to map requires that you also select a date and time; if you do not select a date and time, the most current data set in the PHAiRS database is mapped as the default. You can also change the Background Layer from the initial color DEM to a gray-scale Shaded Relief by clicking on the drop-down arrow and selecting the Shaded Relief layer. After checking the box next to the data layer(s) or selecting a new Background Layer, click Refresh Map, on the map, or on a Navigation button: Previous Extent, Full Extent, Zoom In, Zoom Out, and Directional Pan Arrows. Each time you select or de-select data layers and refresh the map, legend information below the data layer name is updated to represent the symbols and colors used in the map. (De-select a layer by clicking on the checked box — this removes the check and the layer will not be mapped after you refresh your selection.)
ClockThe clock symbol next to a data layer indicates that the data set is time-sensitive, or time-dependent. Selecting a time-dependent data layer to map requires that you also select a date and time; if you do not select a date and time, the most current data set in the PHAiRS database is mapped as the default.
Refresh Map and Select Date and TimeThis box is below the "Background Layers" drop-down menu and contains the Refresh Map and Calendar/Time buttons.
Refresh MapAfter selecting or de-selecting data layers for mapping, click on Refresh Map to redraw the map with your new layers.
Sample Calendar WindowThis image is an example of the window you will see after clicking on the Calendar button. Here, July 10, 2007 8 a.m. UTC (2007-07-10 08:00:00) has been selected. The calendar opens with the current date highlighted; click on the date of interest and use arrows on either side of the month's name to see the calendar page for an earlier or later month. A drop-down menu has options for the years 2003 to present, with the current year as the default. The Hour (UTC) box has 00:00:00 as the default time; use the drop-down menu to select an hour. Time-dependent data sets are updated every 48 hours or longer, depending upon data set validation at its source, so you must choose an hour for the morning before the current day, or earlier. If you do not select a date and time, the most current data set in the PHAiRS database is mapped as the default. Close the Calendar window by clicking on the "Close Window" button or on the window's upper-right corner "x" (the standard browser window ‘close’ control).
Reference MapThe Reference Map is also called the Location Map. This map box is at the bottom of the Legend, Layers, Calendar and Time, and Refresh Map area. The initial reference map is a small version of the base map that opens with the PHAiRS application. As you zoom in or pan to an area, your current map view is indicated by a red outline on the Reference Map.
Northing and Easting CoordinatesBoxes for the Northing (Latitude) and Easting (Longitude) Coordinates are at the bottom left of the map. Coordinates are for your cursor position on the map and are displayed in the standard degrees, minutes, and seconds format — dd:mm:ss N or dd:mm:ss W (N refers to Latitudes north of the Equator, W refers to Longitudes west of the Prime Meridian). Data sets in the PHAiRS mapping application are projected as Geographic, WGS84 Spheriod, WGS84 Datum.
Map SizeThe Map Size drop-down menu has three options for the size of the mapping application box: Small (the default), Medium, and Large. The application box automatically re-draws as a different size is selected. If you have a large monitor screen, you might prefer filling more of the screen with the Medium or Large Map Size.
Map ScaleThe Map Scale box displays the scale of the map that results from each zoom in or zoom out action. The scale is displayed as a ratio.
back to how-to index Basic Mapping Time Series Analysis Selecting Data Layers
Click on the Time Series Analysis button to set parameters for a 48-hour DREAM dust storm forecast. A box will open below the map application with options for particulate matter size, date, city or point of interest, and animation scale. (Click on the Time Series Analysis button to close this set-parameters box.) Note that the resulting analysis might take a few moments to load since it is downloading multiple images for the animation and generating the time series plot. The image below shows the set-parameters box: default settings on top and user-specified date and city on the bottom.
Select a Time Series Target, the first box on the left, is a parameter for Particulate Matter size, PM2.5 or PM10. The default Target is ‘DREAM 48-hour PM2.5’ and a drop-down menu allows you to select ‘DREAM 48-hour PM10.’
DREAM Date is a parameter for the begining date of the 48-hour forecast. The default date is the current date (yyyy-mm-dd) and the user can enter a date of interest, following the same date format. The current-date forecast actually begins the day before the current date because the database is updated every 48 hours. Note: If you refresh the map, the Date will return to the default date and you will have to re-enter your specific date.
Select a City is the parameter for the geographic area of interest for the model. The default city box is blank; the user can select a city from the drop-down menu of alphabetized cities within the DREAM Domain, click on the map at the point of interest, or enter Northing and Easting Coordinates (in the boxes to the right of the Select a City box) using the Degrees, Minutes, Seconds, North Latitude or West Longitude format: dd:mm:ssN/W. If you select a city or click on a point on the map, the corresponding Northing and Easting Coordinates will be automatically entered.
Select a City, Northing, and Easting If you do not wish to select a city from the drop-down menu, then click on the map at your point of interest or enter Northing and Easting Coordinates in the boxes to the right of the ‘Select a City’ box using the Degrees, Minutes, Seconds, North Latitude or West Longitude format: dd:mm:ssN/W. (Projection: Geographic, WGS84 Spheroid, WGS84 Datum) If you do select a city or click on a point on the map, the corresponding Northing and Easting Coordinates will be automatically entered.
Animation Scale has three options: Full Scale, Half Scale, and Quarter Scale. This parameter determines how much of the DREAM Domain will be mapped for the animation. Full Scale will result in an animation for the entire Domain. For Half Scale and Quarter Scale, the selected city or point of interest will be the mapped center point for a half or quarter of the Domain area, respectively.
Run Time Series Once you have selected parameters for Target, Date, City/Northing/Easting, and Scale, click on the Run Time Series button. The currently mapped data layers will be included on the resulting animation map. Note that the results might take a few moments to load since the analysis client is downloading multiple images for the animation and generating the time series plot. Remember, if you refresh the map, the DREAM Date will return to the default date and you will have to re-enter your specific date.
This set of images shows example parameter settings for:
In the image above, the City and Date parameters are displayed in the ‘PHAiRS Dust Animation Client’ title box, at the top. The data layers currently mapped in the PHAiRS application are displayed on the animation map, which is to the left below the title box. The ‘Dust Animation Key’ includes AQI values for the colors green, yellow, orange, red, purple, and brown. Green AQI values are low and brown AQI values are high. Each AQI category is accompanied by the corresponding dust concentration in mcg/m∗∗3 (μg/m∗∗3). The target city is indicated by a light-blue star. For information on the Air Quality Index (AQI), see the Selecting Data Layers section.
The animation speed is in milliseconds (ms); the default speed is 200 ms and the user can select a different speed from the drop-down menu: 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000 ms. Click on the Play button and the animation will continuously loop at the selected speed until it is stopped (click on the ‘stop’ button at the left of the controls). Also, you can move the animation forward or backward frame by frame (use the ‘backward’ and ‘advance’ arrow controls to the right of the Play button). Both the mapped dust forecast and the dust concentration plot (to the right of the map) are controlled with the frame-by-frame options. The image below shows the animation controls: Stop is on the left, followed by Play, Move Backward, Advance (Move Forward), and the Speed drop-down menu.
As the animation plays, the Dust Concentration Plot advances by each hour and indicates the AQI value for the hour. The gray box at the bottom of the map and plot areas tracks the Date, UTC Time, and Particle Size Class. In the image below, the animation was stopped for UTC Time ‘08 hrs’ (in keeping with the example throughout the Time Series Analysis section). Note that the vertical red line in the Plot is positioned at ‘8’ and intersects the blue line at ‘AQI level 2.’
back to how-to index Basic Mapping Buttons and Tools Selecting Data Layers
A Geographic Information System (GIS) allows you to map and explore multiple data layers at the same time. To Select Layers in the Legend/Table of Contents, click on the white check box next to each data layer to be mapped and then click Refresh Map, on the map, or a Navigation button: Previous Extent, Full Extent, Zoom In, Zoom Out, and Directional Pan Arrows. To de-select a data layer, click on the checked box to un-check it and then on Refresh Map, the map, or a Navigation button. Each time you select or de-select data layers and refresh the map, legend information below the data layer name is updated to represent the symbols and colors used in the map.
The PHAiRS mapping application contains data layers for terrain and land surface, air quality, boundaries, and cities. Time-dependent air quality data layers and dust forecasts are for the DREAM Domain, only; all others are for the United States. Background Layers cover most of North America. Data sets in the mapping and time series clients are displayed with Geographic Projection, WGS84 Spheroid, WGS84 Datum.
Data Layer Descriptions
Background Layers:
GTOPO 30 Meter DEM
GTOPO 30-m Shaded Relief
Time-Sensitive Layers:
EPA AirNow PM2.5
EPA AirNow PM10
Albuquerque Ozone
DREAM dust output – PM2.5
DREAM dust output – PM10
Albuquerque Air Quality – Ozone
Albuquerque Air Quality – Ozone (recoded)
Air Quality Monitoring Stations:
Albuquerque PM2.5 Monitoring Stations
EPA AirNow Station Locations
ABQ Ozone Station Locations
Boundary, Cultural, and Land Surface Layers:
State Boundaries
Counties
U.S. Census Tracts
DREAM Domain
Interstates
Interstate Labels
U.S. Highways
U.S. Highway Labels
Local Roads
Local Road Labels
Cities and Towns (Population)
Airports
Federal Lands
Indian Lands
Urban Areas
Wilderness Areas
Water Bodies
Streams and Rivers
back to how-to index Basic Mapping Buttons and Tools Time Series Analysis
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. This PHAiRS 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. NASA has funded the development of DREAM and PHAiRS at the University of Arizona and the University of New Mexico's Earth Data Analysis Center.
See the PHAiRS project Web site for more information. PHAiRS Home phairs.unm.edu
Below the mapping application box are seven logos that link to Web sites for the PHAiRS programming languages and services: MapServer, GRASS, R, PostgreSQL, PostGIS, W3C XHTML1.0 Validation, and W3C CSS Validation. Each logo is described below the image and in the order that it appears, left to right.
MapServerMinnesota MapServer is an Open Source environment for building spatially-enabled applications. MapServer is especially used to render spatial data – maps, images, and vector data – for the Web.
GRASSThe Geographic Resources Analysis Support Systems geographic information system (GIS) is an Open Source GIS with raster, topological vector, image processing, and graphics production functionality, and provides a rich library of geoprocessing functions that can be accessed through a variety of scripting languages. GRASS GIS is released under GNU General Public License.
RR is a free language and software environment for statistical computing and graphics. A GNU project, it is similar to the S language and environment and can be considered a different implementation of S. R provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering, ...) and graphical techniques.
PostgreSQLPostgreSQL is an Open Source relational database system. It is an enterprise-class database with features such as Multi-Version Concurrency Control, point-in-time recovery, tablespaces, asynchronous replication, nested transactions, online/hot backups, a sophisticated query planner/optimizer, and write ahead logging for fault tolerance. It supports international character sets, multibyte character encodings, Unicode, and is locale-aware for sorting, case-sensitivity, and formatting.
PostGISPostGIS adds support for geographic objects to the PostgreSQL object-relational database. PostGIS "spatially enables" the PostgreSQL server, allowing it to be used as a back-end spatial database for geographic information systems (GIS). Released under the GNU General Public License, PostGIS is an open source spatial database technology that features user interface tools, basic topology support, data validation, coordinate transformation, and programming APIs.
W3C XHTML1.0 ValidationWorld Wide Web Consortium (W3C) eXtensible Hyper Text Markup Language (XHTML) validation services check the submitted document against defined constraints for technical specifications, including machine-readable formal grammar and vocabulary.
W3C CSS ValidationWorld Wide Web Consortium (W3C) Cascading Style Sheets (CSS) validation services compare style sheets to the CSS specifications, help find errors, typos, or incorrect uses of CSS, and give warnings when the CSS submitted for validation poses some risks in terms of usability.
For questions, more information, or assistance regarding PHAiRS, please contact Dr. William Hudspeth.
Earth Data Analysis Center
MSC01 1110
1 University of New Mexico
Albuquerque, NM 87131-0001
bhudspeth@edac.unm.edu
Definitions indicated as ESRI definitions are from the on-line ESRI dictionary.
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 definition)
Air Quality
Air Quality Index (AQI)U.S. EPA measure...
AQIAir Quality Index.
AZArizona; a state within the DREAM domain for dust storm forecasts.
back to glossary indexB
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 definition) The PHAiRS Base Map shows a color DEM for North America.
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 definition)
back to glossary indexC
CACalifornia; the southern part of the state is within the DREAM domain for dust storm forecasts.
Cardinal PointOne of the four compass directions on the Earth's surface: north, south, east, or west. (ESRI definition)
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 definition)
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 definition)
Choropleth MapA thematic map in which areas are distinctly colored or shaded to represent classed values of a particular phenomenon. (ESRI definition)
COColorado; a state within the DREAM domain for dust storm forecasts.
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 definition)
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 definition) The PHAiRS 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 definition)
Cultural FeatureA human-made feature represented on a map, such as a road or airport. (ESRI definition)
back to glossary indexD
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 definition) Although the PHAiRS application shows a base map for most of North America, the data sets are only for the United States of America.
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 definition)
Data LayerA Data Layer is a data set that contains spatial information so that it is enabled for mapping. Although the PHAiRS application shows a base map for most of North America, the data layers are only for the United States of America.
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 definition) PHAiRS 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 definitions) 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 definition)
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 definition)
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 definition)
Domain
Drag [a box with the mouse button]Click on the map and keep the mouse button depressed while you draw a box over the area of interest. Release the mouse button to set the box location. The PHAiRS Zoom In tool allows you to drag a box on the map.
DREAM, DReAMDust Regional Atmospheric Model
DREAM Domain
back to glossary indexE
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 definition)
Environmental Protection Agency (EPA)
EPAU.S. Environmental Protection Agency. http://www.epa.gov/
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 definition) See Map Extent.
back to glossary indexF
FeatureA representation of a real-world object on a map. (ESRI definition)
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 definition)
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 definition)
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 definition)
Federal Lands
Full Extent, Full ViewThe limit of the geographic area shown on a map. The PHAiRS Full Extent or Full View is the map that shows most of North America. Click on the Full Extent (Full View) button and the map will change to the North America map, showing the same data layers that were displayed on the zoomed-in map.
back to glossary indexG
Geographic CoordinateA measurement of a location on the Earth's surface expressed in degrees of latitude and longitude. (ESRI definition)
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 definition)
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 definition)
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 definition)
GeometryThe measures and properties of points, lines, and surfaces. In a GIS, geometry is used to represent the spatial component of geographic features. (ESRI definition)
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 definition)
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 definition)
GTOPO
back to glossary indexH
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 definition) The PHAiRS application displays data sets with the World Geodetic System of 1984.
hrhour(s)
back to glossary indexI
IDIdaho; the southern part of the state is within the DREAM domain for dust storm forecasts.
Indian Lands
back to glossary indexK
KSKansas; the western half of the state is within the DREAM domain for dust storm forecasts.
back to glossary indexL
LatitudeThe angular distance, usually measured in degrees north or south of the Equator. Lines of latitude are also referred to as parallels. (ESRI definition)
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 definition)
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 definition) 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 definition)
Location1) An identifier assigned to a region or feature. 2) A position defined by a coordinate value. (ESRI definitions)
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 definition)
back to glossary indexM
mmeter(s). Unit of length in the International System of Units, equal to 39.37 inches.
m∗∗3meters 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 definitions)
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 definition)
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 definition)
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 definition)
msmillisecond(s); one one-thousandth of a second.
back to glossary indexN
NASA, N.A.S.A.U.S. National Aeronautics and Space Administration. http://www.nasa.gov/
NASA REASON
NENebraska; most of the state is within the DREAM domain for dust storm forecasts.
NMNew Mexico; a state within the DREAM domain for dust storm forecasts.
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 definition)
NVNevada; a state within the DREAM domain for dust storm forecasts.
back to glossary indexO
OKOklahoma; the western half of the state is within the DREAM domain for dust storm forecasts.
OROregon; the southeastern corner of the state is within the DREAM domain for dust storm forecasts.
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 definition)
back to glossary indexP
PanTo shift a map image relative to the display window without changing the viewing scale. (ESRI definition)
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.
PM 2.5Particulate Matter consisting of particles less than 2.5 microns in size.
PM 10Particulate Matter consisting of particles less than 10 microns in size.
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 Mapping Client
PHAiRS User GuideThe User Guide includes information on the PHAiRS 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).
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 definitions)
PMParticulate Matter.
PM 2.5
PM 10
PointA geometric element defined by a pair of x,y coordinates. (ESRI definition) 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 definition) 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 definition)
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 definitions)
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 definition) PHAiRS Projection: Geographic, WGS84 Spheroid, WGS84 Datum.
PropertyAn attribute of an object defining one of its characteristics or an aspect of its behavior. (ESRI definition)
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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 definition)
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 definitions) 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.
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 definition)
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 definitions)
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 definitions)
back to glossary indexS
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 definition)
Scale Dependence
SDSouth Dakota; the southern part of the state is within the DREAM domain for dust storm forecasts.
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
Site DisclaimerThe Site Disclaimer section displays information about the PHAiRS policies for Web privacy, data and application use, and your responsibilities as a Web user at this site.
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 definition)
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 definitions)
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 definition) PHAiRS 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 definition)
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 definition)
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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 definition)
Table of Contents (also called Legend in the PHAiRS application)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 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 definition)
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 definition)
TerrainAn area of land having a particular characteristic, such as sandy terrain or mountainous terrain. (ESRI definition)
TextureA digital representation of the surface of a feature. (ESRI definition)
Thematic DataFeatures of one type that are generally placed together in a single layer. (ESRI definition)
Thematic MapA map designed to convey information about a single topic or theme, such as population density or geology. (ESRI definition)
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 definition)
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 definition)
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 definition)
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 definition)
TopographyThe study and mapping of land surfaces, including relief (relative positions and elevations) and the position of natural and constructed features. (ESRI definition)
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 definition)
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 definition)
TXTexas; the western two-thirds of the state is within the DREAM domain for dust storm forecasts.
back to glossary indexUVW
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 PHAiRS 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/
UTUtah; a state within the DREAM domain for dust storm forecasts.
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 definition)
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 definition)
WYWyoming; the southern half of the state is within the DREAM domain for dust storm forecasts.
back to glossary indexXYZ
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 definition)
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 definition)
ZoomTo display a larger or smaller region of an on-screen map or image. (ESRI definition)
Zoom InIn PHAiRS, click on the map and keep the 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. The zoomed-in map view is two times larger than the view you clicked on.
Zoom OutIn PHAiRS, 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. The zoomed-out map view covers two times more area than the map that you clicked on.
back to glossary indexPHAiRS Disclaimer (July 2007)
PHAiRS Privacy Notice (July 2007)
PHAiRS Conditions of Use (July 2007)
W3C Validations for XHTML 1.0 Strict and CSS were performed on 31 July 2007. Evaluation for conformance to the W3C Web Accessibility Initiative was performed on 31 July 2007, using the Web Accessibility Versatile Evaluator (WAVE) 3.0 Web Accessibility Tool. The W3C conformance logo will be placed on the PHAiRS User Guide in August 2007.
© University of New Mexico 2007