Hello, I am working with discrete data instead of gridding. I need the area in degree^2 of polygons surrounds those data points. In gridding process, we first assume that the grids are rectangular and the area equals to: area1 = [ delta_latitude * delta_longitude] Afterward, we multiply that value with cos(latitude) to give the actual curvature to the grid which is related to the actual position of the grid in the sphere; area_final = area1 * cos(latitude) I created Voronoi polygons for each data point with "Create Thiessen Polygons" function in ArcGIS and the function automatically gave me an "area" value for each polygon in the attribute table. I am wondering if those area values are already considered the curvature and the actual position of the polygons? Should I also multiply the area with cos(latitude)? Thanks in advance, Feyza
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