Lightning density map
?hexbin may get you started.
Clint Bowman INTERNET: clint at ecy.wa.gov
Air Quality Modeler INTERNET: clint at math.utah.edu
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On Fri, 15 Feb 2013, Bogdan Antonescu wrote:
Hi , I am trying to plot a cloud-to-ground lightning density map for Romania. The data set contains: date(year/month/dat), time(hh/mm/ss), latitude, and longitude for each lightning flash. The density maps were based on dividing the study area into a grid cells (e.g., 20-km to correspond with the audible range of thunder). I have used ArcGIS to calculate a density value for each cell by counting the number of lightning flashes within the cell and dividing by the cell area. The density value (flashes km?2) is then assigned to each cell. Can someone help me on how to do this in R? Thank you very much, Bogdan
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