Projecting Google Earth KML files in ArcMap so that they display properly

Question

I have downloaded a KML point file from Google earth and I imported it into ArcMap. I cannot figure out what to do in order to project it correctly. My dataset is set to WGS 1984 UTM zone 34N and the KML file is in WGS 1984. The difference of the file's display in ArcMap and Google earth is not that dramatic but some points fall into the sea which is bad for the anaysis I am trying to perform. I tried to project the Google earth point file in WGS 1984 Web Mercator (Auxiliary Sphere), but it still didn't display properly.

Can you explain how it works with Google Earth and ArcMap projections?

The DEM is from ASTER, it is tile N36E022, west Greece (Europe), http://gdem.ersdac.jspacesystems.or.jp/search.jsp. The KML point file is not public but was created for use in Google Earth.

Answer 1

Apply below transformation method to project your data in ArcMap.

1)Open New Arcmap.

2)Add your Imagery files which you downloaded from Google earth.

3)Add your existing geodatabase layer files into arcmap (Ex:Layers or shapes)

4)Right click in the Arcmap window and select Dataframe Properties.

5. A New window will open and then select your Layer file (Google/Imagery file) and then click Transformations Now you need to choose correct datum in Convert from: location and then Into: location and you need to choose your datum(Co-ordinate system) in this case my Datum is Asia\Qatar 1974 and choose appropriate using: method and click Ok. and APPly.

6. Now check your map if it's aligned properly or not, if not and then come back to the same location open Dataframe properties this time you need select Projected Coordinate System and select National Grids choose your national grid and hit Apply Now your data should be aligned properly.

Answer 2

I have downloaded the ASTER data you mentioned, and got an offset of around 120m.

I'm afraid that's all the ASTER database is able to offer. They promise an offset of 20m at 95% of the world, but you can not rely on that.

The data is in WGS84, same as Google Earth. So it is not a matter of datum shifts at all.

If you want a more precise shoreline, you can take that of Openstreetmap, linked and described here: http://wiki.openstreetmap.org/wiki/Coastline#Rendering

The processed_p shapefile is much closer to the aerial imagery than the aster data.

If you want height contour lines, you might use ASTER anyhow.

Answer 3

The Easiest way to do this before you add the data or imagery is :

1. Open ArcMap
2. right click the Layer properties
3. Hit the Coordinate System tab.
4. if you have the 10.0 or later: Type the name of the coordinate system ie:(WGS 1984 Web Mercator (Auxiliary Sphere)).
5. Select it.
6. Bring in the data
7. right click on the data and select Data to Export Data
8. On the Export Data dialog box : Choose "the data frame" ( Make sure you select it right)
9. Review the the data source to ensure it is correct coordinate system or you can test it by clear out the "Clear Search"