When you start using a GPS receiver, you’ll soon discover that it’s pretty numbers-oriented. There’s time, speed, distance, altitude, and (of course) the location coordinates. But quite often you’ll want names to go with those numbers. Or you might need to convert those coordinate numbers into another format. That’s where this topic comes in. Read here to discover how to locate places by their names and get their coordinates (and other information) and how to easily convert coordinates from one coordinate system to another.
Sometimes you need a little bit more information about a location.
You know a place name, but you don’t know exactly where the place is located.
You’ve heard about a place but don’t know whether it’s a mountain peak, a river, or a town.
You generally know where a place is, but you need the exact latitude and longitude or Universal Transverse Mercator (UTM) coordinates.
In these cases, you can turn to a gazetteer, which is a collection of place names with such useful data as geographic coordinates, elevation, and feature type. Gazetteers are usually published as topics, but digital versions are available. The U.S. government has two free online gazetteer services:
GNIS provides information about places in the United States. GNS has information about locations all over the world.
Using the Geographic Names Information System (GNIS)
The Geographic Names Information System (GNIS) is the federal repository of geographic name information. The database contains information on nearly 2 million physical and cultural geographic features in the United States and its territories: a city, dam, island, school, or any other designated feature type. You can search for feature information at the GNIS Web site: http:// geonames.usgs.gov.
The GNIS search page has a number of different data fields (as shown in Figure 11-1) that you can use to narrow down your search, including
Feature Name: This is the name of the feature you’re looking for. This can be either the whole name or a part of the name.
Feature name searches aren’t case sensitive.
Query Variant Name?: Some features have other names in addition to their primary name. If you select the Yes radio button, records with matched variant names are displayed.
State or Territory: From this drop-down list, select the state or territory where the feature is located.
Figure 11-1:
Search for geographic information by entering what you know about a place.
County Name: If you click the County Name button, a drop-down list box shows all the counties in the currently selected state.
If you know the county where the feature is located, enter it to speed up your search.
Feature Type: The Feature Type drop-down list box contains all the feature types, such as bridges, canals, lakes, and populated places. If you know what the feature is, select its type.
Elevation Range: The Elevation Range text boxes let you search for features that occur at a certain height range; use feet when entering the range values.
Topo Map Name: You can confine a search to features only found within a United States Geological Survey (USGS) 7.5 minute topographic map by entering the map’s exact name.
Follow these steps to perform a basic search for a feature:
1. Go to the GNIS Web site at http://geonames.usgs.gov.
2. Click the Query GNIS: U.S. and Territories link.
3. Enter the feature name that you want to search for in the Feature Name text box.
4. From the State or Territory drop-down list box, select the state where the feature is located.
5. Click the Send Query button.
Finding street address coordinates
Commercial services can provide the information latitude and longitude of a particular street address, such as www.geocode.com (you can test drive their Eagle geocoding technology for free), but here’s also another free and easy method:
1. Go to the www.terra-server-usa.com site and enter a street address.
2. Select an aerial photo of the location.
An aerial photo displaying the street address of the location is displayed with a pushpin icon shown on top of the address.
3. When the photo is displayed, click the Info link at the top of the page.
A grid appears over the aerial photo with the latitude and longitude coordinates of the address.
The accuracy of this information varies, but usually it puts you in the general vicinity of the address you want. If you really want precise information, visit the address with a GPS receiver and record the coordinates.
The more you narrow a search, the faster it is. For example, if you know the county where a feature is located, select it. If you don’t know much information about the feature, be patient. The GNIS server can be pretty slow.
If GNIS finds any records that match your search criteria, it lists all the matching features. Figure 11-2 shows that a search for Horse Butte found three matches. Information about the features includes
Feature name
State
County
Feature type
Latitude and longitude
USGS 7.5 minute map that the feature appears on
If you aren’t sure which result you need, use this information to narrow your search.
Figure 11-2:
GNIS search display results.
After you pick a feature, click its Feature Name link to display more information. A new page displays additional information including:
Elevation: The elevation of the feature is displayed in feet.
TopoZone.com link: Clicking this link goes to the TopoZone.com Web site and shows the feature location on a USGS topographic map.
FIPS55 Place Code: Federal Information Processing Standard (FIPS) 55 contains codes for named populated places, primary county divisions, and other locations in the United States. Click this link to display the FIPS55 code for the location; unless you know that you need this, the code isn’t very relevant for the average user.
Digital Raster Graphic (DRG) link: Click this link to display the feature location on a digitized version of a USGS topographic map; supplied by www.terraserver-usa.com.
Digital Orthophoto Quadrangle (DOQ) link: Click this link to display a black-and-white aerial photograph of the feature location, supplied by www.terraserver-usa.com.
Tiger Map Server: Click this link to display a road map of the feature area prepared from U.S. Census Bureau data.
Watershed: Click this link to visit U.S. Environmental Protection Agency (EPA) maps and information about the watershed where the feature is located.
You need an Internet connection to access the GNIS database. In addition to the online search capabilities at the GNIS Web site, you can download text files of all the features and associated information for each state. The files are quote- and comma-delimited and can be opened with your own databases and spreadsheets. The files come in compressed and uncompressed formats; if you have a slow Internet connection, download the Zip files.
Ever wanted to name a mountain or another land feature after yourself or a loved one? The U.S. Board on Geographic Names is responsible for naming and renaming features that appear on USGS maps. If there’s an unnamed geographic feature, you can propose a new name for it (or suggest a name change for an existing feature). The Board even has an online form that you can fill out. Submitting the form doesn’t guarantee you’ll automatically get some peak named after Uncle Harry; this is a rather big deal. For instructions on filling out the online form see http://geonames.usgs.gov/dgnp/ dgnp.html.
Figure 11-3:
Detailed information from the GNIS database.
Using the GEOnet Name Server (GNS)
The GEONet Name Server (GNS) searches for features around the world. GNS is located at http://earth-info.nima.mil/gns/html/index.html.
The database contains over 3.5 million features and over 5 million place names for locations outside of the United States. The military relies on GNS for its operations, so the database is updated every other week.
GNS is primarily designed for military use. Some of the search criteria and information in the database isn’t very useful to the average civilian. At best expect to find these types of information for a given feature:
Country Type
Latitude and longitude
To perform a basic GNS search for a feature, follow these steps:
1. Go to the GNS Web site at http://earth-info.nima.mil/gns/html.
2. Click the Access GNS link.
3. Click the GNS Search link in the GNS Main Menu at the left of the page.
You can enter search criteria by scrolling down the page.
4. In the Name text box, enter the name of the feature you’re looking for.
A drop-down list box to the right of the text box lets you narrow your search with these options:
• Starts With
• Is an Exact Match
• Contains
• Ends With
5. If you know the country the feature is located in, select the country from the list.
6. Click the Search Database button.
Figure 11-4:
TheGNS search page.
Waypoint repositories
A number of Web sites provide waypoints that you can upload to your GPS receiver. (A way-point is a set of coordinates for a location.) With these waypoint repositories, you can search a region or for a feature name for its waypoints in a database. If a waypoint has been logged in the site database, you can download the waypoint and then upload the coordinates to your GPS receiver. Some of the waypoint sites include
http://wayhoo.com: This site converts GNIS and GNS feature information into waypoints. There are also coordinates for airports and a database where users can upload waypoints.
www.travelbygps.com: This site holds a collection of waypoints for interesting places all over the world, including photos and descriptions. The site has an extensive collection of links to Web sites with special interest waypoints.
www.trailregistry.com: This is a waypoint collection dedicated to hikers and backpackers.
www.trailwaypoints.com: This is a GPS repository site that collects recreation-oriented waypoints from all over the world.
For GNS advanced searches, you can enter an extensive list of feature types as part of your search criteria. These include oil pipelines, refugee camps, and vegetation types. Other options limit searches by the latitude and longitude boundaries of a rectangle, use special character sets from foreign languages, and use government and military codes as part of the search. If you want to run these advanced searches, the GNS Web site has links with explanations.
If GNS finds records that match your search criteria, the features appear on a new page. A number of pieces of information are displayed (as shown in Figure 11-5). For the average civilian user, the most useful data includes Name of the feature.
Region of the world where the feature is located. Click the link to get an explanation of the abbreviation.
Designation: The feature type (such as populated locality, farm, or reservoir). Click the link to get the definition of the abbreviation.
Latitude and longitude coordinates.
Area: Country and state or province information for the feature. Click the link for the meaning of the code.
You can also download tab-delimited text files from the GNS Web site for any country that contain features and information. This data can easily be imported into spreadsheets and databases.
Figure 11-5:
The results of a GNS search for Orinoco.
