Abstract: Interactive and static maps are proliferating on web sites of local and state agencies in Utah. Concurrently, the number of GIS datasets download requests made to Utah's State Geographic Information Database (SGID) continues to grow. With these developments in mind, the Utah Automated Geographic Reference Center (AGRC), working with the State of Utah Chief Information Officer, is implementing a strategy to make online maps and GIS data easier to use and more accessible. This paper discusses the implementation of the maps.utah.gov online map index; the SGID GIS dataset download indices that make more than 15,000 GIS datasets available for download via the Internet; an HTML-based ArcIMS template designed for public, non-GIS literate audiences; and mapit.utah.gov, an internet-based location mapping application.
The Utah Automated Geographic Reference Center (AGRC) is charged with facilitating effective GIS-related efforts in Utah and maintaining Utah's State Geographic Information Database (SGID). These two responsibilities make AGRC a focal point of GIS activity in Utah and an ideal coordinator for the many internet-based GIS mapping efforts within the state. This coordination effort has included several projects relating to the organization and accessibility of internet maps and GIS datasets. These include: 1) the maps.utah.gov online map index, 2) the SGID dataset download indices, 3) the development of an ArcIMS HTML-based map viewer designed specifically for public audiences, and 4) the mapit.utah.gov location mapping application.
AGRC, together with the State of Utah CIO's initiative for enterprise IT solutions, is focusing on efforts to leverage the value of information content contained in online maps and the SGID. This is being done by looking for ways to improve the ease of use and accessibility of geographic information. Toward this end AGRC is maintaining an online map indices, building an expandable architecture to support the atlas.utah.gov ArcIMS sites, and prioritizing the design of internet mapping applications in order to maximize the impact and audience reached.
Over 100 internet map sites pertaining to the State of Utah already exist online. These sites are hosted by a great variety of agencies and other entities. AGRC, with help from the CIO's office, has designed maps.utah.gov, an online catalog that provides a central index to these sites. The maps.utah.gov site (see Graphic 1) allows users to sort map sites by subject matter, geographic extent, and hosting agency. It also displays a list of frequently requested maps and maps pertaining to current issues. All indexed maps include a title, brief description, ratings of difficulty & speed, and links that allow the user to view the map in a new browser window. The maps.utah.gov site is updated periodically with new map sites. The number of links made to each map from the maps.utah.gov site are tracked and used to update the list of frequently requested maps. State, and local govenment agencies can request that their maps be added to map.it.utah.gov via email from the sites contact information page.
As part of its responsibilities, AGRC is the administrative steward and repository for Utah's State Geographic Information Database (SGID), the state's enterprise-wide GIS data library. The SGID database contains approximately 140 thematic GIS data layers that describe land use, demographic, environmental, infrastructure, historical, and political features throughout the State. These layers are provided free of charge to government agencies, the private sector, educators, and the general public via the Internet. AGRC is an National Spatial Data Infrastructure (NSDI) Clearinghouse Server node and makes the SGID and its metadata availabel through the NSDI program.
The SGID Dataset Download Indices website (agrc.utah.gov/sgid.html#index) contains GIS datasets indexed by name, subject, file type, file size, and geographic extent. Many of the SGID statewide datasets are also available as export files clipped to specific geographic extents, including those of Utah counties, 1:250000 USGS Quads, 1:100000 USGS Quads, and 1:24000 USGS Quads. This results in over 15,000 datasets available for download on AGRC's website (agrc.utah.gov). In order to make this data more accessible, AGRC built a database of the GIS datasets within its ftp site and used this database in conjunction with ArcView Avenue scripts to construct an HTML-based data index for each geographic extent for which data is available (see Graphic 2). Using the dataset download indices, users can quickly see what data is available, view FGDC-compliant metadata for these datasets, hyperlink to export files on AGRC's ftp site, and be advised of other scales and extents that they may wish to examine in their area of interest.
AGRC is currently implementing a website that provides access to the SGID using the Metadata Explorer extension available for ArcIMS 4.0. With the ability to display datasets, provide metadata and spatial queries, and use 'drag and drop' methods to load datasets into ArcGIS from the new SGID SDE/Oracle database, this site will ultimately supercede the dataset download indices site in its ease of use. However, the dataset download indices site will still be available for those who prefer to download export and shapefiles within self-extracting zip files. The dataset download indices site will also soon be expanded to include ArcGIS layer (.lyr) files. These .lyr files will include query and legend parameters for connecting and displaying datasets from the SGID SDE/Oracle database.
In order to improve usability of ArcIMS sites, AGRC has developed an HTML map viewer interface that is specifically designed for use by the general public. This public interactive map interface consists of a simple tool and button set to interact with ArcIMS map services. The design goal fo this map viewer was to provide a GIS-style functionality to users who have little or no familiarity with a GIS or commonly employed GIS user interfaces.
The public map template is currently being utilized for a number of state agencies' ArcIMS sites including the Utah Conservation Data Center's (UCDC) wildlife interactive map (see Graphic 3) and the SGID interactive map (see Graphic 4). The UCDC's interactive map allows students and the general public to view wildlife habitat and the distribution of endandered species of plants and animals throughout Utah. The SGID interactive map provides hyperlinks to the SGID dataset download indices. Users can select the type of extent for which they are interested and then click on the map to view and download, via hyperlinks to the AGRC ftp site, all file-based GIS datasets available for individual USGS quads and counties within the state. The public map template includes zoom, pan, identify, hyperlink, find, print, legend, reset, and help functionality as well as the ability to zoom to cities and counties in Utah. Users are able to change the thematic map layer that is displayed and queriable and can also change the background layers.
In late summer 2002, AGRC's map server site (atlas.utah.gov) will contain links to all ArcIMS interactive maps that employ the public map template. Users will be able to display and examine GIS data concerning a range of subjects such as air quality, demographics, land ownership, transportation, and natural resources.
The mapit.utah.gov application was designed as a distributed solution for location mapping within Utah. AGRC was presented with a request by the State Web Product Manager for an application that would enable state agencies to include a hyperlink from every address or location on a state web site to a map that visually describes that location. The mapit.utah.gov site contains two principal components. The first component is a map authoring tool (see Graphic 5) that enables the creation of a map request URL that produces custom, static or interactive maps for locations in Utah. This map request URL contains parameters that determine the extent of the map, a label location, up to two lines of label text, and whether the map is static (image only) or is accompanied with interactive map tools. The second component is the map viewer interface (see Graphic 6) that displays when the map request URL is opened in a browser.
A custom ArcIMS HTML interface was constructed to implement the map authoring tool. After selecting a lower left extent corner, upper right extent corner, and label location, the user types in the label text and clicks a button to generate the resulting map request URL in a text window. This URL can then be copied and pasted into a browser window or web page to request the custom map. Alternatively, an HTML <a> tag is generated that can be pasted into a web page. This <a> tag contains the map request URL and a short javascript which opens a new window of the size specified (using size parameters set in the authoring tool) and brings the map window to the forefront of the browser. The map authoring tool purposely avoids geocoding as a means for selecting the location to be mapped and labeled. Allowing the map request URL creator to specify the extent and label location parameters allows for greater flexibility in displaying the mapped location, and, makes it possible to map locations that have no known address or are not represented correctly in the street network GIS database.
The map viewer interface contains a simple interface that the user can employ to interact with the location map. The user of the map viewer can interact with the map by selecting the zoom in, zoom out, or pan tools and clicking directly on the map image. Additionally, buttons provide ten preset zoom levels, directional panning, access to a legend, a full extent function, and map help. A pull down list enables map viewer users to zoom to preset geographic extents including Utah counties and cities. As the user zooms in and out of the map, the amount of geographic feature detail and labeling changes so as to provide a neat map graphic at a variety of map scales.
There are several advantages of the mapit.utah.gov site over other online location map services. First, AGRC has full control the GIS data from which the map background is drawn and the content of the authoring and viewing interface. Second, map request URLs can be created in a decentralized manner. Webmasters can create simple map images or interactive maps without GIS software, GIS software skills, and without having to contact AGRC to make arrangements or get permission. Third, the mapit.utah.gov site does not require that the address of the location to be mapped be known or included in a geocode dataset. Although a geocoding interface may be added at a later date, the site is not dependent on street addressing for making location maps.
Interactive and static map offerings are proliferating on Web sites of local and state agencies in Utah. Concurrently, the number of GIS datasets download requests made to Utah's State Geographic Information Database (SGID) continues to grow at an appreciable rate. Utilizing a variety of technologies including ArcIMS, AGRC will continue its efforts to increase the amount of map-related content and geographic data available to the government agencies and the public while striving to improve the organization and ease of use of this valuable information.