I have a polygon shapefile in CRS EPSG:27700 British National Grid that is a boundary of a study area that I would like to load into the iTree Canopy online tool. https://canopy.itreetools.org/index.php

The tool uses Google Satellite as its basemapping so in QGIS I have saved the layer with CRS EPSG:3857 WGS84

But when I try to load it I receive the error 'Invalid projection format'

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The pop-up help tells me that the shapefile must be 'reprojected to geographic coordinates'

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I have looked at the help video which essentially describes what I have tried to do above using QGIS - ie. reproject the shapefile into WGS84.

I also tried based on another web search using the Vector > Geometry Tools > Export/Add Geometry Columns

Is there something obvious that I am not doing?

  • 3
    Maybe you have to reproject to the WGS84 long/lat coordinate system? The epsg code is 4326 (not 3857) – Micha Mar 2 at 11:20
  • Thanks, I hadn't registered there were different EPSG codes for WGS84. My shapefile now saved as EPSG4326 no longer gives me the 'Invalid projection format' error message. – Martin Hügi Mar 3 at 0:01

Perhaps the iTree site needs layers in the Long/Lat geographic coordinate system, EPSG code 4326 (not 3857). EPSG 4326 is geographic and based on WGS84, whereas 3857 is projected also based on WGS84.

WGS84 is a datum, not a projection. There are many (hundreds, maybe even thousands)) of projections based on the WGS84 datum. For example there's a whole set of UTM projections which are based on the WGS84 datum. Each with slightly different projection parmmeters. So it's not enough to day "WGS84 projection".

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