Can't mashup a WMS map that's not in the same basemap projection...

[RobbyWilson]

When I load in a WMS (http://gis.ncdc.noaa.gov/webservices/ibtracs/tracks/MapServer/WMSServer?request=GetCapabilities&serv...) for the Global Tropical Storm Tracks into an existing ArcGIS OnLine map in web Mercator, get the following error:

The item, tracks, can not be added to the map because its coordinate system can't be adjusted to align properly with the basemap. So, the basemap always sets the projection..right? So, what are the best practices for ingesting multiple data/maps in different projections into an existing ArcGIS map or to mash-up? Told there are there global server config settings/options to handle this problem so maps in disparate projections can to be read into an existing map or to support a dynamic mash-up capability using the ArcGIS.com viewer.

Can this projection problem be corrected if server is configured from the source map projection to 102100/3857?

[MikeMinami]

Yes, the basemap sets the coordinate system for the web map.

You can set the WMS service to be the basemap of your map (there is a checkbox when adding the WMS to the map that says "use as basemap"). If you do so, any data you add over it will need to conform to the coordinate system of the WMS service.

If you can configure your WMS service to support the web mercator aux sphere projection, I think it should work.

As far as mashing up layers from different sources, there is no magic here...all the data sources need to be able to display in the same coordinate system. If you use one of the provided basemaps, it's web mercator. Or you can use your own basemap.

Hope this helps,

Mike