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I would like my map to show more color differences between sites that have 1-200 turbines. I have 1-293 turbines per location. However I would like to show the areas that have higher numbers as having more of an impact. For example the area that is in the upper right hand side is a very clustered area and a bird is more likely to hit a turbine in an area of high density. I hope that makes sense. Sorry if I need to explain more let me know. I am using ArcGIS 10.1 and my data came from USGS wind energy website. The attributes within that I am interested in are location, and total number of turbines. However my problem is that with such a large area I am having a large amount of over lap and unneeded noise. I am trying to figure out the best way to show large farms or clusters of farms without 20 points all within the same location.

my heat map based on point density

  • Welcome to GIS SE! Can you edit your question to include more information about software and data? – Barbarossa Apr 25 '17 at 15:24
  • Okay I edited it I hope that made it more clear – Monika Burchette Apr 25 '17 at 15:30
  • So you downloaded the attached raster from the USGS, or did you download point data and create the heat map? If you created it, what methods were used? What's the range of value of the raster? Have you tried changing the symbology color ramp to achieve more desirable results? – Barbarossa Apr 25 '17 at 15:55
  • I created it using Kernal density I used the point data and selected the population field of total_turb I changed the cell size to 30 (the default was 4179.58) I did not input a search radius I place my area units a hectares. I kept the output values as densities and the method as method planar. I place a hill shade and I have tried to adjust the symbols but they are not changing much. – Monika Burchette Apr 25 '17 at 16:10
  • I know you are using ArcMap but QGIS has a really straightforward heatmap plugin and symbol style for point features... – atxgis Apr 25 '17 at 16:58
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If I understand correctly, you have a set of points with values attached that represent the number of turbines at each site, so a site with one turbine and a site with 200 both have one point in the dataset. If that's the case, simple buffering might be what you're after. You indicated you wanted only different colors to represent the number of turbines, but I'm going to assume you also want different sizes showing magnitude, as that's the usual case.

For example, let's assume there's a field named count in your point shapefile that is the number of turbines at each site. Run Buffer, select Field under Distance and choose count or some field you've calculated with the appropriate display distance, for Dissolve Type choose List, and again select count. Once this completes, open up Properties > Symbology > Categories > Unique Values > Add all values, then choose a color ramp. This gives you something along the lines of:

enter image description here

If you want the same size for each buffer regardless of number just use the Linear Unit option under Buffer. Another thing you may want to tweak is grouping various classes (e.g. 1-50, 50-100, etc.). To do so you can select multiple classes under symbology and group them together (right-click), or add a field in the attribute table, then use Field Calculator along with some formula such as (Int ([count]/50) + 1)*10 or a set of If statements if the intervals are not even (e.g. 1-25, 25-50, 50-100, 100-200, etc.).

Another solution, if you have or can get individual points for each turbine, is to use Euclidean Distance to produce a raster layer showing the area of influence of each individual turbine, but this is probably better suited to finer-scale visualization than what you're doing. For example:

enter image description here

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