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I have several TIN files representing empty lakebeds at altitudes ranging from 5000m to 3000m. I have calculated the TINs using ArcGIS hydrology tools and an ASTER v3 DEM projected to WGS_1984_UTM_Zone_43N.
The DEM data as well as a folder containing the TIN data for several of the lakebed depressions can be found here: https://drive.google.com/open?id=1ERFdsqDGLH1a_FbxwawE_gPm0Au0Q9vT

I want to present the depth of the lakebeds in an appealing way.
I can change the symbology type to elevation but then the same color ramp is used for every lakebed, regardless if it is 10m or 100m deep - the deepest part in every lake has the same color. Therefore, at first they all seem to have the same depth:

enter image description here

I would rather have the parts of all lakes with a depth of 5m, 10m, 15m etc. to have the same color coding so that I would be able to tell the depth difference between the individual lakes at a glance. Is there a possibility to tweak the appearance of a TIN to display not the absolute altitude but its individual depth?

  • Could you add to your question with an example image of the TIN data you are working with, and any other pertinent info about the data? – CrystallineEntity Nov 1 '19 at 18:05
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To obtain strictly bathymetry, subtract the TINS from a DEM with "filled" waterbodies using a raster calculation such as the Minus tool in ArcGIS. This will bring all of the lakes to the same elevation and allow for the desired symbology.

If the desired effect is to scale all depth values to the same color ramp, then you may want to merge all of your bathymetry rasters. You can also do this with symbology, by setting the min/max values of your TINS to the same range, rather than their own individual data range.

For instance, one lake's depth values may range from 0-20m, but inclusively all of the lake's depths range from 0-120m. You set every lake's symbology to 0-120m and you have a unified depth symbology.

In ArcGIS you may go to the symbology window and change the ramp to a Min-Max and enter values manually.

If the lake depth rasters do not overlap and/or conflict, then it may be easiest to simply merge them all and assign one symbology to the result.

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  • This would be the solution to my problem, I think, but the problem with this suggestion is that my lakes lay at different altidudes. For example: one lake is at 5000m and is 20m deep, the other is at 3000m and is 100m deep. So I cannot just assign one symbology to 0-120 m because the range in altitude is enormous. – Florian Mlehliv Oct 30 '19 at 8:25
  • I think the key here is to convert elevation to depth. Subtract the ground elevation from the water surface elevation to obtain depth. One all the elevation TINS are converted to depth values, they can all be presented with the same symbology. – Scott La Vanne Oct 30 '19 at 19:16
  • The answer was modified to reflect changes to your question. – CrystallineEntity Oct 30 '19 at 20:13
  • I'm sorry, but I wasn't entirely clear with my wording because I did not think it important: The lakes are not filled with water at the moment. They are just sinks that will fill up eventually... So I have no "filled-waterbodies DEM" to substract the TIN from. – Florian Mlehliv Nov 1 '19 at 8:26

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