Lesson 10f: The national map Dynamic Elevation Web
Service: Add to ArcMap, Raster Processing Templates,
and Spot Elevation. This video tutorial shows how to
use the national Maps 3D Elevation Program or 3DEP
elevation web map service in ArcMap.
By the end of this lesson, you will be able to add Dynamic
Elevation Web Coverage Service to ArcMap, enable raster
processing templates, and retrieve a spot elevation.
The Dynamic Elevation Map Service creates multiresolution
visualizations on the fly from digital elevation models,
allowing users to explore a variety of representations,
including hillshade, aspect, slope, and tinted hillshade maps.
as well as automated contours and more.
Open Geospatial Consortium web map service and web coverage service interfaces
are enabled to support interoperability across systems.
The web coverage service allows access to the underlying data
for analysis and visualization in GIS software.
The dynamic platform supports the exploration of 3DEP
digital elevation models or DEMs for the US and territories at a
mixture of scales, including one
meter DEMs. High resolution elevation data will continue to
become increasingly available as 3DEP progresses toward its
goal to acquire national LiDAR coverage by 2023 with
IFSAR data in Alaska.
In the dynamic service, the most current, highest resolution
elevation data available are highlighted as the user zooms
into larger scales.
Availability and scales of data vary by location.
Data sets are described on the 3DEP products and
Services Web page.
To add services to ArcMap you will need to know where to find
the most up-to-date service URLs. These are available at
viewer.nationalmap.gov/services
Service URLs are subject to change in the future, but as of the publishing date of this
video, the service address for the dynamic elevation services
shown here. Information regarding the Dynamic Elevation
service is located in the web coverage service is drop down.
To begin, you must be using Arcmap version 10.3 or a more
recent version. This functionality is also available
in Arcgis Pro.
To access the dynamic elevation service in Arcmap, begin by
opening the program.
Next, click the add data button.
In the ad data dialog box, click on the option for GIS servers.
Then double click add ArcGIS Server. It's important to select
the add ArcGIS Server and not the add WCS server option as
the elevation service may not work properly if it is added as
a WCS server. Once you've clicked add ArcGIS Server, a new
dialog box pops up. Of the available options, select 'Use GIS
services, then click next. Then copy paste the URL of the
3DEP. Elevation web service into the box labeled server URL.
Leave the authentication box is blank as authentication
is not required for this web service. Click finish to add
the web service to ArcMap.
To add the elevation service to your map, open the catalog
window. Expand The list of GIS servers by clicking on
the plus sign and you should see the elevation service in
the list. Expand this list by clicking on the plus sign and
you will see the 3DEP Elevation Service. Click and
drag this icon into your map to add the elevation service.
When the service is added, it is zoomed to full extent and a
hillshade of North America will be visible on a blank
background. You will also see the elevation service listed as
a layer in your table of
contents. Zooming into a smaller area of interest allows the web
server to load more quickly as it is requesting a smaller area
of data. Try zooming in closer to an area with mountainous
terrain such as Yosemite
National Park. This elevation service has several different
display modes enabled, such as slope, aspect and elevation
tinted hillshade.
This can be accessed using raster processing templates.
To access the processing templates, right click on the
three depth elevation layer in the table of contents and select
properties. In the layer properties dialog box, select
the processing templates tab.
On this tab you can select from a drop down list of
preconfigured display modes.
The default display mode is Hill Shade Gray. The way the layer
initially loads. For demonstration purposes, select
the hillshade elevation tinted option. Then click apply to
apply the processing template.
The result is a hillshade colored by elevation. Several
other processing templates are available and can be
applied the same way. For example, the aspect map.
And slope map.
To return to the default view, select the hillshade Gray
processing template. It should be the first
in the drop down list.
Next, let's explore another capability of the Dynamic
Elevation Service. Since it is a WCS, we can access the actual
elevation data rather than simply seeing a static image.
First turn off the hillshade Gray processing template to see
the elevation data as a flat
raster. In the processing templates dropdown, select the
option 'None' at the very bottom
of the list. This will change the display to a raster with no
hillshading. Now by clicking the identify tool at any
location, you can retrieve the elevation at that point in
meters. Note that in order to retrieve elevation information,
the processing template option must be set to none.
In this lesson, we discussed how to add the dynamic elevation
WCS ArcMap, enable raster processing templates, and
retrieve a spot elevation.
Please visit the National Map Services page For more
information about our web map services.