ArcGIS Explorer 440 includes enhancements which make it easier to use and manage dynamic layer content from services that are continually being updated, like weather or active fire perimeters.
When you connect to one of these services you have full control over the refresh interval, and with Explorer 440 the cache for dynamic layers is automatically refreshed on open, so you’ll always have the latest information. This now applies to all content sources, including both 2D and 3D services published via ArcGIS Server, 2D services published via ArcIMS, or local vector and raster data.
In this example we’re going to use a weather service provided by Meteorlogix, one of ESRI’s business partners. The Meteorlogix weather information service that ESRI taps into provides updated information every 15 minutes, and the data is being manipulated and stored in an Oracle-based enterprise geodatabase. As part of the geodatabase input process the data is generalized somewhat (for performance) and cell-based information is aggregated into polygons. As the data is refreshed in the geodatabase it is also being date-stamped, so that historical weather trends can be analyzed using ArcGIS Desktop’s Tracking Analyst.
In ArcGIS Explorer we’re interested in adding this service as a dynamic layer which refreshes automatically. To do this, we connect to the service in Explorer by choosing File, then Open, and selecting Server as the content type we wish to open.
Below we’ve clicked ArcGIS Server from the Create New Connection choices along the top, and have provided the necessary connection information to connect to the ESRI internal server that is publishing the weather (sorry, we don’t yet publish weather as a publicly accessible service).
Now that we’ve established a connection to the server, we can scroll down and see the list of published services that are available. Below we’ve chosen to connect to the Meteorlogix weather service that we described above.
Now that we’ve chosen the weather service, we’re guided by a wizard to specify certain parameters. Note that there is a user option to remember what we’ve specified the next time around.
First we’re asked to specify the raster cell size, for which we accept the default chosen by Explorer. Next we’re asked to choose from among the sublayers published in this service. And now to the important part – we’re asked to specify the disk caching options. Since the weather data is updated on the server every 15 minutes, we’ll choose the option for “Don’t create a cache for the layer on disk.” This also enables the choice for refreshing cache based on a time interval, and we’ll specify 15 minutes as the refresh rate.
Using these settings Explorer will communicate with the server and refresh cache for this layer every 15 minutes. If the map is saved, when opened again it will automatically refresh the layer, then refresh at the specified 15 minute interval, ensuring that what you see is up to date.
You can experiment with this yourself using any service or local data source. For a detailed discussion on cache and various cache management options, refer to the Cache management in ArcGIS Explorer Help topic.