Frequently Asked Questions--Details
Using Geography Network Explorer
There are two ways to find geographic
content using Geography Network Explorer: by searching
or by browsing.
Then, use the Explorer to view
search/browse results.
Searching
You can search by place name, geographic
extent, content type, content theme, and keyword. Your search
can include one or more of these search criteria. Specify
the geographic extent by typing a place name or by zooming,
panning, and selecting a location on a map of the world.
Once you have executed your search, view the search results
in the right panel.
Each method has its advantages.
Use a combination of search criteria to narrow your search
results. For example, if you choose the United States as
the geographic extent but do not specify a content type
or content theme, Geography Network Explorer returns metadata
for all data sets covering the United States. If you are
only interested in transportation networks or only want
to find downloadable data, specifying a content theme or
content type will narrow your search results considerably.
Find detailed instructions below
for
Searching by geographic extent
Searching by content type
Searching by content theme
Searching by keyword
Searching for geographic content
Searching
by Geographic Extent
If you know the name of the area
for which you want geographic content--for example, Orange
County, California--it may be easiest to type it in the
text box and click Find. If you do not know the correct
name for the area or you want to search for a larger area--for
example, the area around Los Angeles--zoom in and select
it on the map.
When you type a place name and click
Find, Geography Network Explorer returns a list of matching
places. You might have been thinking of the state of Georgia,
but your search results also include the country of Georgia
in Asia, the city of Georgia in Indiana, Georgian Bay in
Canada, and so on. Click the place you are looking for in
the list of place names that appears in the right panel.
The map of the world on the left panel zooms to the place
that you selected.
As an alternative to searching by
place name, use the Zoom In, Zoom Out, and Pan tools to
find an area on the map. Once you are zoomed in enough to
see the area, use the Select Search Area tool to select
it.
Searching
by Content Type
You can search for three types of content: data, documents,
and resources. Each category has a number of subcategories.
Search for
- Data
if you want to download, order, or add data or map services
directly to your map
- Documents
if you are interested in map files and geographic information
- Resources
if you are looking for links to external Web sites, data
clearinghouses, GIS-based Web applications, and geographic
services
Searching
by Content Theme
A content theme is a categorical description of the features
in a data set. Agriculture and farming, human health and
disease, oceans and estuaries, and imagery and basemaps
are examples of content themes that you can choose. Sometimes
a content theme precisely describes what you are looking
for, making your choice simple. Other times, you are not
sure how to classify the data. If you are not sure whether
the soil data you are looking for is classified as agriculture
and farming or environmental, you could search twice (once
by each category) or you could search by selecting All Data
Themes.
Searching
by Keyword
Searching by keyword is an excellent way to narrow your
search results. If you are searching for something specific
like satellite data, typing the keyword "satellite" limits
search results to data sets with detailed descriptions including
"satellite." Sometimes, however, the keyword limits your
search too much, eliminating data sets that might have been
useful to you. For example, even though a RADARSAT image
is, in fact, a satellite image, its list of theme keywords
might not include "satellite."
If you are going to include a keyword
in your search criteria, it is a good idea to repeat your
search using other words with a similar meaning. For example,
if you are interested in rivers, you might try "rivers,"
"streams," "hydrology," "drainage," and so on.
Searching
for Geographic Content
- Type a place name,
click Find, and click a place name in the right panel
or use the zoom, pan, and selection tools to select a
location on the map.
- Specify any combination of the
following: content type, content theme, and/or keyword.
- Click the content type drop-down
arrow and click Data, Documents, Resources, or one of
their subcategories.
- Click the content theme drop-down
arrow and click one of the available themes.
- Type a keyword.
- Review your search criteria.
If you typed a keyword, check it for typographical errors.
- To extend your search to the
Geospatial Data Clearinghouse, check Search NSDI Clearinghouse.
- Click Search. Search results
are displayed in the right panel.
If you checked Search NSDI Clearinghouse,
the Geography Network NSDI search application opens. Search
additional servers and view additional search results. Click
Close when you are finished.
Browsing
All metadata documents are organized in a hierarchy
of directories and subdirectories, making them easy to browse.
When you click a directory, a list of subdirectories appears.
Click each directory to see its subdirectories, and so on.
The right panel lists the data sets
belonging to the current directory. The title and publisher
of each data set are provided. Often the coverage area and
map scale are provided as well. You might also see a thumbnail
image of the data. You can view the detailed metadata for
each record and, in some cases, view a map of the data as
well.
To browse metadata
- Click Browse.
- Click a directory in the left
panel. A list of subdirectories appears.
- Click a subdirectory. A new list
of subdirectories appears.
- Repeat step 3 to continue drilling
down.
- Once you have arrived at the
directory you want, scroll through the list of the contents
in the right panel.
- Click View Details to view a
data set's detailed metadata, or click View Map to view
a map of the data.
Viewing
Search/Browse Results
If you searched for data, the results of your search
are summarized in the right panel. If you browsed to a directory,
the contents of the directory are listed in the right panel.
If searching or browsing returned more than one type of
content, the records are listed by content type.
Use the scroll bar to move through
the list of data sets. The description of each data set
includes the name of the publisher, the content title, and
often the coverage area and map scale.
Find detailed instructions below
for
Viewing metadata
Viewing a map of the area
Adding data to ArcMap, ArcExplorer,
or ArcExplorer Web
Printing search results,
metadata, and maps
Viewing
Metadata
Viewing the complete metadata for a data set will either
confirm your initial impression about its suitability or
eliminate it as an option. Pay particular attention to the
access and use constraints because these also affect the
suitability of the data. If you want the data for a use
prohibited by the publisher, you will have to find another
data set.
The Metadata tab also allows you
to view the coverage area. This is particularly useful when
you cannot view a map of the data. A green box indicates
the coverage area. To view metadata
- Find a data set that interests
you by browsing or executing a search.
- Click View Details beneath the
record in the right panel. The Details tab appears.
- Examine the metadata for the
selected data set.
- Scroll down and click View Coverage
Area.
- A new window appears showing
a map of the world zoomed in to the coverage area of the
selected data set. A green box outlines the coverage area.
- Click Close when you are finished
looking at the coverage area.
Viewing
a Map of the Area
Geography Network Explorer has several navigation tools
that allow you to pan and zoom a map of the data. Use these
tools to take a closer look at different features of the
map. This option is only available when the metadata references
live data. To view a map area
- Find a data set that interests
you by browsing or executing a search.
- Click View Map beneath the record
in the right panel. A map of the data appears in the right
panel.
- Click Zoom In, Zoom Out, or Pan
on the toolbar to change the map extent.
- Click Zoom to Full Extent to
return to the full extent of the map.
Adding Data
to ArcMap, ArcExplorer, or ArcExplorer Web
If you launched the Geography Network Explorer from ArcMap,
ArcExplorer, ArcExplorer Web, or the Geography Network,
an Add to ArcMap, Add to ArcExplorer, or Add to ArcExplorer
Web button is available from the Search Results. Click this
button to add the selected data or service directly to your
current ArcMap, ArcExplorer, or ArcExplorer Web map display.
Printing
Search Results, Metadata, and Maps
Anything that appears in the right panel of the Geography
Network Explorer can be printed. This includes maps, metadata,
and search results.
The printable version of search
and browse results excludes the View Details and View Map
buttons. The printable version of the map excludes navigation
tools. To create a printable version
- Click the Create Printable Version
button in the upper right corner of the right panel. A
new browser window appears containing the printable version.
- Click File and then click Print
to open the Print dialog box.
- Click OK on the Print dialog
box.
- Click Close at the bottom of
the browser window to close the printable version.
Using Geographic Content
Most Geography Network content can
be used with one of two tools: a standard Web browser or
a GIS software package. Web browsers can be used to access
content such as map services, solutions, and clearinghouses.
Other content, including map data files and data services,
require GIS software to be fully utilized. Content is divided
into
- Data, which can be added directly
to your map, downloaded, or ordered.
- Documents, which include map
files, static map images, and other documents.
- Resources, which are GIS-based
Web applications, geographic services, links to external
Web sites, and data clearinghouses.
When choosing a content type, consider
the level of interaction you want to have with the data
and whether or not you want to download it to your own machine.
Data
Dynamic
Data and Maps: GIS users can access "live" data and
map services, such as ArcIMS
or WMS map services, using software tools such as ArcExplorer
Web, ArcGIS,
and ArcExplorer--Java
Edition. ArcExplorer Web provides a way to view multiple
image services and perform basic queries such as identify
and find.
ArcGIS, ArcMap, ArcExplorer--Java
Edition, and ArcExplorer Web include links to add map services
directly from the Geography Network. These links launch
a customized version of the Geography Network Explorer that
can be used to find a map service. Once an appropriate map
service is found, click Add to ArcExplorer Web, Add to ArcMap,
or Add to ArcExplorer to add the map service to your map
view.
Users can visually combine multiple
map services by using the image transparency options or
integrate local data with the map services.
Documents
Map
Files: Map files are digital maps that can be viewed
in a mapping application such as ArcReader or ArcMap. Map
files are typically completed maps that are ready for viewing,
publishing, and printing.
Static Maps: You cannot directly
interact with static map images as you can with live data
and maps. You can view them and download them to your computer.
Other Documents: This category
includes geographic information stored in text files, spreadsheets,
or other formats and can be used in conjunction with geographic
data. In many cases, they can be viewed and downloaded.
Resources
Applications:
An online application is built using Geography Network content
or other Internet-hosted data. The application includes
a complete user interface and a set of geographic content
needed to perform one or more tasks.
Clearinghouses:
A clearinghouse is a Web site that contains references and
links to a variety of free geographic data. Many clearinghouses
offer geographic data for download while other sites include
metadata references or hyperlinks to data sets that may
be acquired through other mechanisms.
Content Types
Three types of content can be found
on the Geography Network: data, documents, and resources.
- Data,
which can be added directly to your map, downloaded, or
ordered.
- Documents,
which include map files, static map images, and other
documents.
- Resources,
which are GIS-based Web applications, geographic services,
links to external Web sites, and data clearinghouses.
When choosing content, consider
the level of interaction you want to have with the data
and whether or not you want to download it to your own machine.
Data
This content type includes downloadable
data, offline data, and data that can be added directly
to your map.
Dynamic
Data and Maps: Dynamic data and maps are geographic
services that allow direct interaction with map content.
This type of content is published to the Geography Network
as "Live Data and Maps" and delivered to users in one of
two ways.
- Cartographic images or "snapshots"
of maps
- Compressed vector features that
are streamed to you
Dynamic features allow for greater
client-side interaction including dynamic labeling, feature
symbolization, and MapTip creation. Users do not need to
download anything to use live data--they can just add it
to a map and begin exploring. ArcIMS and WMS services are
in this category.
Documents
This content type includes static map images and text
or tabular information that is used in conjunction with
geographic data.
Map
Files: This category includes any digital maps that
can be viewed in a mapping application. Maps created for
ArcReader and ArcMap are examples of digital maps that fit
into this category.
Static Maps: Static Map Images
are map image files. You cannot directly interact with static
map images as you do with live data and maps. You can view
them and download them to your computer.
Other Documents: This category
includes geographic information stored in text files, spreadsheets,
or other formats. These documents are used in conjunction
with geographic data. In many cases, they can be viewed
and downloaded.
Resources
This content type includes links to external geographic
data sources, GIS applications, and geographic services.
Applications:
This category includes custom-built GIS applications. These
applications usually have a complete user interface. ArcIMS
Viewers belong in this category.
Clearinghouses:
Clearinghouses are Web sites that either provide links to
free geographic data or allow you to directly download it.
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