I have reclassified a raster layer into a 2-class polygon layer and I need to calculate the area of these 2 class polygons. This has to be done in continent level (how many square km of class 1 are in Europe for example).
I have done it through calculate geometry. My questions are, if the "calculate geometry" tool gives a reliable result when it deals with so large areas and if I have to do the calculation in the specific projection I use per continent. The projection I use for each continent has an impact on the calculated area or it is irrelevant so I can do all calculations in the same world projection? For the world projection I use the Robinson and for every continent I use different (for example I use North_America_Albers_Equal_Area_Conic for N.America)
Thanks in advance!
I would suggest you to calculate Geodesic Area, since it considers Earth's curvature and gives you more accurate area.
or using Calculate Field like
Thank you very much for your reply. Yes, I have used this tool to calculate Geodesic Area, so I suppose it is correct.
In the "calculate geometry attibutes", in coordinate system I used the WGS_1984_Web_Mercator_Auxiliary_Sphere and Robinson projection for all my calculations in all continents. My question is, if due to distortions, these calculations are not reliable and I have to use each continent projection for area measurements. Or if it is irrelevant and using the same coordinate & projection system for all continents is correct.