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For reference, I found another Q&A with an answer to this same question for QGIS but I am looking for an ArcMap solution: Quartiling a vector buffer in QGIS 3.6.

I am trying to figure out if there is a way to cut the buffers into the needed cardinal quadrants. The goal is to then dissolve the four buffers for a point into one buffer that shows how the radius changes for each quadrant.

For context, I am working with NOAA hurricane data that has wind radii data values that extend in four directions: NE, SE, SW, and NE. Each value represents how far in each direction certain levels of wind speed extended at different points (every six hours). We create buffers out of those wind radii data to figure out where certain levels of wind speed intersect with different counties of the United States.

Our former ArcGIS analyst created circle buffers by taking the minimum of the four directional values: That is, if at a certain point a hurricane had a certain category of wind speed’s extending 25 miles NE, 50 miles, SE, 75 miles NE, and 70 miles NW she would create a simple circle buffer using the minimum value: a buffer with a radii of 25 miles (ArcPy code for this method and illustration at the end of this post).

What I would like to change is illustrated at the end of this post: I would like to create for partial circles with different radii that extend according to the four distances in the NOAA data. What ArcMap tools could I use to create the partial circled with different radii for a single point? I have done some research on my own and the only resource I have noted are multiple ring buffers, which, to my knowledge, cannot be made into partial circles.

Even a method to separate a circle buffer into four quadrants would be helpful. I think from there I could work on manipulating the radii of the separated vectors.

Sample ArcPy code for current approach:

arcpy.AddField_management("radii34","Buff_34","DOUBLE")

arcpy.CalculateField_management("pts","Buff_34","min_val( !NE50WR!, !SE50WR!, !SW50WR!, !NW50WR!)*1000", expression_type="PYTHON_9.3",

code_block='def min_val(a,b,c,d):\n if a == "-999":\n return 0\n else:\n return(min(a,b,c,d))')


arcpy.Buffer_analysis("pts","Hurricane_Buff34","Buff_34",line_side="FULL", line_end_type="ROUND",dissolve_option="NONE", dissolve_field="",method="PLANAR")

enter image description here

PolyGeo
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Brendan Leonard
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    Like a Wind Rose? https://desktop.arcgis.com/en/arcmap/latest/extensions/business-analyst/wind-rose-report.htm – Mapperz Oct 21 '19 at 20:28
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    look up arcpy.WindRoseReport_ba https://desktop.arcgis.com/en/arcmap/latest/tools/business-analyst-toolbox/wind-rose-report.htm#C_GUID-A2B56C98-B47F-4433-8C17-89D24ABF1502 – Mapperz Oct 21 '19 at 20:30
  • Yes, the Wind Rose report tool with four sectors would seem to do the trick! Thanks - I had not heard of it before. – Brendan Leonard Oct 21 '19 at 20:42
  • Out of curiosity is there a way to do this without the Wind Rose report? It would require a license purchase on our end and I was hoping to be able to do this with our ArcMap Pro license. – Brendan Leonard Oct 23 '19 at 16:05
  • Polar Plots by Jeff Jenness http://www.jennessent.com/arcgis/polar_plots.htm – Mapperz Oct 23 '19 at 16:29

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