Regridding data from a custom projection to a LatLon Fishnet - Zonal statistics?

Discussion created by oderbolz on May 26, 2011
Dear ArcGIS users,

I need to convert tree coverage data (each cell contains a percentual coverage of a given tree species) from polar-stereographic projection (cellsize 50x50 km) to a rectangular LatLon grid (0.25x0.125 deg).  The projection is easy to change, but of course, the cells do not align with the target cells (they are tilted by about 45 degrees).

This is what I did:
- FeatureToRaster (the input data is not a raster yet)
- ProjectRaster
- ZonalStatistics using my target fishnet shapefile

But as you can see in the attachment, the resulting field does not at all follow the coastlines (which it already does not in the input).

Here are my questions:
- is zonal statistics really the tool of choice for this task?
- how can I quickly clip the data to the land surface?

Thank you very much for any input on this matter.