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<TITLE>question about merging DEMs at the edges</TITLE>
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<FONT FACE="Verdana, Helvetica, Arial"><SPAN STYLE='font-size:12.0px'>In my project, we are patching together ASTER DEM’s. The ones generated with the new software from USGS are very nice. However, there remain artifacts at the edges. Largely due to the fact that each DEM, in UTM projection, is projected onto the earth’s sphere in slightly different locales, when you patch them together, the edge of one doesn’t exactly match the elevations of the adjacent one. In a few spot tests today, the difference is pretty small <= 15m in elevation. But this is still enough to cause problems in hydrologic modeling if your watershed happens to fall in 2 different DEM’s (as ours does). <BR>
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So does anyone have a suggestion as to how we can smooth out the artificial scarp that occurs when we patch together a couple adjacent DEM’s like this?<BR>
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Michael<BR>
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Michael Barton, Professor of Anthropology<BR>
School of Human Evolution & Social Change <BR>
Center for Social Dynamics and Complexity<BR>
Arizona State University<BR>
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phone: 480-965-6213<BR>
fax: 480-965-7671<BR>
www: <a href="http://www.public.asu.edu/~cmbarton">http://www.public.asu.edu/~cmbarton</a> <BR>
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