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I have what looks like a hole in my DEM! I don't think it is affecting my calculations, but either way, I would quite like to correct it.

Does anybody have any idea how?

Please see the attached picture to understand what I mean.

enter image description here

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  • How and from what did you create the DEM?
    – Martin
    Jun 11, 2014 at 8:40

1 Answer 1

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I had the same problem using some SRTM DEMs. Besides from using some later and more correct version or another data source, I'd recommend setting all values below some chosen threshold (that will only select the hole pixels) to NoData (=erase them) and then re-interpolating them according to the surrounding pixels so that there will at least be no excesses.

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  • Yep, just taken a look at my data and there was one value which appeared as -9999, deleted it and its now fine. There is a noisy section of the DEM at that point so maybe it is something to do with that.Thanks
    – Katie C
    Jun 11, 2014 at 9:27
  • Just to be clear, you don't want to alter ("delete") the original data, but rather set the -9999 values to noData, so ArcMap will understand those pixels as such. I'm not so sure which you did..
    – reima
    Jun 11, 2014 at 9:36
  • Ahh I did delete it. How to you set the -9999 to noData?
    – Katie C
    Jun 11, 2014 at 9:40
  • What ArcGIS considers to be NoData depends on the raster format used; in some of them -9999 means NoData, in some of them not. I'd try a few conversions (such as to ESRI Grid) and see if the -9999 disappears to NoData. Jun 12, 2014 at 9:04

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