2

I just downloaded the shapefiles for the County boundaries in Minnesota from here.

Now I am expecting the boundaries of the Polygons/MultiPolygons to consist of latitude and longitudes (according to the metadata). Instead on loading the shapefiles I see huge numbers which don't seem like lat/long coordinates.

enter image description here

enter image description here

If you look at the last column in the tables (within the images) I am unable to understand what those numbers represent and how I can convert them to latitudes and longitudes.

The .prj file contains:

PROJCS["NAD_1983_UTM_Zone_15N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-93.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]] Is it possible to get the shape file for the county boundaries such that the locations are mentioned in latitude/longitudes? Could you give me some suggestions?

4
  • The shapefile set likely includes a .prj -- Please Edit the Question to contain its contents as text (which is likely State Plane). By using images to show text, you obscure it from some devices and search engines.
    – Vince
    May 30 at 19:22
  • @Vince I have added the .prj file thanks! May 30 at 19:29
  • And so you've mostly answered your own Question -- the data must be reprojected from NAD83 UTM Zone 15 (technically, unprotected and possibly transformed) to the target geographic coordinate system. What have you tried?
    – Vince
    May 30 at 19:35
  • @Vince I haven't tried transforming to state plane coordinates since the remaining part of my algorithm expects the boundaries to be in latitude/longitude coordinates. Is it possible to get the shape file for the county boundaries such that the locations are mentioned in latitude/longitudes? Thanks! May 30 at 20:17

1 Answer 1

4

Usually, information about the CRS can be found in the metadata file.

Section 4: Coordinate System Horizontal Coordinate Scheme: Universal Transverse Mercator

UTM Zone Number: 15

Horizontal Datum: NAD83

Horizontal Units: meters

Vertical Datum: not applicable

Vertical Units: Not Applicable

Depth Datum: not applicable

Depth Units: Not Applicable

As well as when reading the shapefile with GeoPandas, one can get the EPSG:26915.

import geopandas as gpd

zipfile = 'D:/TESTING/shp_bdry_counties_in_minnesota.zip!mn_county_boundaries_500.shp'
# url = 'https://resources.gisdata.mn.gov/pub/gdrs/data/pub/us_mn_state_dnr/bdry_counties_in_minnesota/shp_bdry_counties_in_minnesota.zip'

gdf = gpd.read_file(zipfile)

print(gdf.crs) #epsg:26915

And then reproject with gdf = gdf.to_crs("EPSG:4326") if needed.

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.