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I have two layers, one of points (locations of fruit trees) and one of Atlanta zip codes, in an ArcMap, but the layers are not aligning. The zip codes are in the top right and the fruit points are tiny in the bottom left corner.

enter image description here

I successfully converted the fruit points to a shp file from a csv file. The fruit points in the csv are decimal coordinates taken from a GPS.

The zip code map is in NAD83.

**I should have also included that I set the fruit projection to NAD83 (the same as the zip code map). If I understand correctly, this is what is being suggested to me -- but I have already done so. The fruit is a shp layer and the zip codes are as well.

How would I go about aligning these layers so the points fall correctly over the zip code map? Using ArcGIS10.

Thanks in advance.

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    You need to specify the CRS that the fruit trees data is in and that will depend on what the GPS was set to when the tree locations were recorded, so ask whoever used the GPS. ArcMap will then be able to reproject on the fly, but for best alignment and practical use I would actually reproject your trees data to NAD83 and save as some sort of feature class. – MappaGnosis Mar 7 '14 at 14:59
  • Just a little comment, you have a print-screen button on your keyboard, so you dont need to take a picture :P – Below the Radar Mar 7 '14 at 16:00
  • Or if you have a snipping tool, that gives you more selection to capture the screen. Go to All Programs --- Accessories ---Snipping Tool – PROBERT Mar 10 '14 at 15:03
  • I'm pretty sure that "NAD83" is actually a state plane or UTM projected coordinate system. If it isn't, it may not have a correct coordsys either. Can you add the layer's extents to the Q? If you open up the data frame properties, what are the details for the zip code layer. – mkennedy Mar 11 '14 at 17:36
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My guess is that the fruit data 1) has no defined coordinate reference system, 2) it's been assigned the same as the zip code data, or 3) assigned the data frame's coordinate reference system (CRS).

The zip code data and the data frame may be using the same coordinate reference system. If so, it's a projected one like a UTM or State Plane zone. The fruit data is using a geographic coordinate system, likely NAD 1983. In either case, if the fruit data's CRS is either unknown or set to a projected coordinate system, it will show up far to the southwest when the data frame's using a projected CRS.

Define the fruit data with geographic coordinate systems, North America, NAD 1983. Refresh the map and it should line up.

  • Thanks! If you could take a look at the edit I made yesterday and let me know how that changes things, I'd really appreciate it. – cgt Mar 11 '14 at 15:12
  • You're close! You need to set your fruit's CRS to GEOGCS["GCS_WGS_1984"] then use the ArcToolbox's "Project" tool to convert your GPS lat/longs into the same projection as your zip codes. – Mintx Mar 14 '14 at 21:18

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