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Using Line Density on Lat/Lon Polylines

Question asked by coppermann on Apr 23, 2012
Latest reply on Apr 24, 2012 by coppermann
I opened a new map in ArcMap 10 and used the Central USA template. I loaded an Excel spreadsheet with many lat lon points (and other information) in to ArcMap and used Display XY Data... to plot the lat lon points, using the default coordinate system of the map (which appears to be GCS_North_American_1983 and a Projected Coordinate System of North_America_Albers_Equal_Area_Conic). I then used the Geospatial Modelling Environment (what used to be Hawth's Tools) to take the points and create polylines. I then want to use the Line Density tool on the lines, but I want to have a cell size of 10000 m (or 10 km x 10 km). When I put 10000, I think it assumes I'm meaning 10000 degrees since the data is in lat/lon. When I try to project the polylines to North_America_Albers_Equal_Area_Conic, it just changes the coordinate units from degrees to m (i.e., from -88.5 degrees to -88.5 m when in reality it should be about 670000 m) without actually converting the lat/lon to what I assume would be UTM. Do I have to go through the hassle of trying to figure out how to convert the lat/lon points in my spreadsheet to UTM then plot the UTM points or is there an easier way to solve my problem?

Cody Oppermann
Grad Student
Department of Earth and Atmospheric Sciences
University of Nebraska - Lincoln