topic Re: Problem with Skewed Line Artifacts in DEM Data in Water Resources Questions

Problem with Skewed Line Artifacts in DEM Data

JonathanVillines — Thu, 17 Jan 2013 14:41:11 GMT

Hello All,

I am having a problem with the DEM data I am using obtained from the NED; as you can see in the attached images, there are diagonal/skewed line artifacts running throughout the raster that are (I assume) going to make the results of my stream network and catchment delineations inaccurate. I am curious if anyone has seen this and knows what the cause might be? I can only think that it must result somehow from geographic transformation or something else in the spatial reference, but I have done the same procedure on data from the same source before many times and never experienced this issue. There were no problems as far as I could tell in manipulating the spatial reference information.

Any advice or guidance would be sincerely appreciated. Thanks in advance! 😛

-Jon Villines

Re: Problem with Skewed Line Artifacts in DEM Data

ChristineDartiguenave — Wed, 20 Mar 2013 15:55:07 GMT

These are an artifacts of how the NED DEMs were created from the contour lines. You may see more or fewer of those depending on the process used. The dem and fdr are still good. On the other hand, you may want to use the more recent nhdplus dataset.

Here is an article about the NED:
http://www.asprs.org/a/publications/pers/99journal/march/1999_mar_289-296.pdf

Christine Dartiguenave
Esri Water Resources Team

Re: Problem with Skewed Line Artifacts in DEM Data

Anonymous User — Fri, 12 Apr 2013 08:52:12 GMT

Original User: Renaldo09

DEM data are often used in analyses without quantifying the effects of these errors. A method for simulating uncertainty that is implemented as an extension for the ArcView/Spatial Analyst GIS environment was developed. Users can evaluate DEM uncertainty using DEM metadata and spatial characteristics of the DEM. Monte-Carlo simulation techniques were used to represent DEM uncertainty and its effect on various topographic parameters (slope, upslope area, and the topographic index) often used in hydrologic analyses. Different methods for representing error and quantifying uncertainty were investigated.

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Renaldo09