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I am trying to project a shapefile in QGIS that I downloaded from: http://www.dartmouthatlas.org/downloads/geography/hrr_bdry.zip

As downloaded the shape files are not projected. The geographic coordinate system is North American Datum 1983. The problem I'm having is that the US is horizontally stretched, and from what I've read, this problem is because the shapefile is unprojected. This is my first experience working with GIS. I've tried Vector-->Data Management Tools-->Define Current Projection and changed Output CRS to North_America_Albers_Equal_Area_Conic, but this made the map disappear.

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    It probably didn't disappear, but radically changed in size. Right-click on your layer and select "zoom to layer". – JoshC Mar 20 '18 at 15:58
  • More likely than not, at least one of your files isn't in the asserted projection. – Vince Mar 20 '18 at 16:39
  • Try defining your projection as NAD83 geographic first, and then, use the Reproject Layer Tool and set the output CRS to Albers. Perhaps you tried to define the layer's CRS directly as Albers, which won't work. – FSimardGIS Mar 20 '18 at 16:49
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    Also, I noticed that in the data you mentioned, Alaska and Hawaii are not placed in their correct geographical location, but near Texas instead, as if they placed it there solely for layout purposes. This is generally a very bad idea in GIS, since the correct coordinates are not preserved, and it can lead to issues when trying to use the data for processing, analysis, mapping, etc. – FSimardGIS Mar 20 '18 at 16:56
  • If you do want a map with Alaska and Hawaii located in the Gulf of Mexico, it's probably best to work from a shapefile showing them in their correct locations. Then you can arrange these states where you want in your output by using separate map frames in the print composer. – csk Mar 22 '18 at 17:10
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Load the shapefile into QGIS and select WGS84 (EPSG 4326) as the coordinate reference system. enter image description here

By using a base layer, we can confirm that QGIS has the shapefile in the correct location. enter image description here

To visualize the map not horizontally stretched, change the CRS of the QGIS project. Using "on-the-fly" reprojection, QGIS will display the map in a different projection without the need to re-project the shapefile. Make sure "on-the-fly" CRS transformation is turned on in the project properties.

enter image description here

For example, here's what it looks with the same project in USA_Contiguous_Albers_Equal_Area_Conic. As the name implies, this projection maintains relatively accurate areas on the scale of the entire contiguous United States. Distances and shapes may be distorted at the expense of keeping area accurate.

enter image description here This is all you need to do if you just want the map to look less horizontally stretched.

If you need to do calculations, you should re-project the shapefile into an appropriate CRS. Choose a CRS appropriate to the type and scale of calculations you plan to do. Some CRS's are good for area calculations, while others are better for distance calculations. If you're working on a state or county level, choose the UTM CRS specific to that state.

For example, Ohio has these options:

  • NAD83 / Ohio North
  • NAD83 / Ohio North (ftUS)
  • NAD83 / Ohio South
  • NAD83 / Ohio South (ftUS)

NOTE: This particular shapefile has Alaska and Hawaii displaced on top of Mexico. Any calculations including those states could be hugely inaccurate. If this is important to how you'll be using this shapefile, you should correct this issue before proceeding. I would recommend posting another question dealing with that issue separately.

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