Sunday, 8 September 2019

arcgis desktop - Obtaining correct area values *With* correct projections?



I'm trying to get the percentage of each U.S. county overlaying groundwater (data from the census and USGS respectively). They're both polygons.


I have 1) correctly projected the data and the layer (NAD 83, meters) 2) clipped the counties using a polygon corresponding to groundwater coverage 3) use calculate geography to obtain the areas, so that I can then figure out proportions/percentages. I create a new field for that (double).


I've been toying around with this and other methods, and I cannot get credible area values. They're tiny; almost all 0.01 - 0.1. One of my many hunches was that it's in decimal degrees, but I've projected the data, and it's still showing up incorrectly. The most frustrating part is that the county/state files won't calculate correctly either on their own, which is bizarre (Florida = 15 m2).


Any ideas?





No comments:

Post a Comment

arcpy - Changing output name when exporting data driven pages to JPG?

Is there a way to save the output JPG, changing the output file name to the page name, instead of page number? I mean changing the script fo...