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I'm working with a bathymetry raster for the coastline of British Columbia. Data found here: http://bcmca.ca/datafeatures/eco_physical_bathymetry/

I would like to create a new raster that shows the distance to the 1000 m isobath for any given cell.

I know how to create a line feature from the bathymetry raster that depicts the 1000 meter isobath, but I don't know how to create a raster of the distance to the isobath.

My main problem is that the original bathymetry raster has a very unusual shape (because of edges, coastlines, etc), and I would like to mimic the shape and retain NA values in my new raster.

I've tried the following in ArcMap 10.3

  • I used the "Contour List" tool in Spatial Analyst to create a polyline of the 1000 meter contour
  • I then used the "Euclidean Distance" tool to calculate distance to the polyline. The problem with this, is that the resulting raster is a square that does not match the bathymetry raster.

I would like to keep the outline the same, and keep the landmasses and islands as NA values, which makes me think R might be more appropriate.

  • What have you tried? Please edit your question to include a snippet of the code you've tried, and what happens when you try it. – Midavalo Feb 6 '17 at 20:58
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    Set environment extent to extent of bathymetry raster. Everything you are trying is easy in ArcGIS, but you need ask 1 question per post – FelixIP Feb 6 '17 at 21:15
  • @FelixIP thanks for the suggestion. I set the cell size and extent to match that of the bathymetry raster. Is there a way that I can check that the cells of the two rasters are perfectly in alignment with each other? – Splash1199 Feb 6 '17 at 21:49
  • Use snap raster in environments to make rasters perfectly aligned – FelixIP Feb 6 '17 at 21:50
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    @FelixIP, your two comments, with perhaps a screenshot or two, would be sufficient for an answer, in my opinion. – Fezter Feb 6 '17 at 22:14
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Issue: "The problem with this, is that the resulting raster is a square that does not match the bathymetry raster".

Many spatial analyst tools will result in output raster extent equal to envelope (what you call square) of input feature(s).

Best practice here is defining of relevant environmental variables before running any tool (or from tool interface). Three most important are: extent, cell size and snap raster.

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