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I have produced and compiled random points (blue) and data points (red) that are spread across Europe - but when I try to represent them on a baseline map, I have a shift that appears between the points and the map. This can be clearly seen in the lower right part near Crete, where the red points should be on the island.

enter image description here

The baseline map is a Raster Layer and the points are kept within a data frame which contains the coordinate (longitude & latitude).

The CRS arguments for the baseline are as follows:

> crs(baseline_EU[[1]])    
CRS arguments:
     +proj=laea +lat_0=52 +lon_0=10 +x_0=4321000 +y_0=3210000 +ellps=GRS80 +units=m +no_defs

but I do not know the CRS arguments for the points:

> crs(P.points)
[1] NA

I do not know how to solve this issue, so I would really appreciate your help. Many thanks.

EDIT: here is an extract of the raw data. It contains latitude and longitude informations, plus a column that tells that it is a presence point.

enter image description here

Also, maybe this can helps, but following Robert Hijmans' advice I have checked the CRS arguments of the data points on QGIS:

EPSG:4326 - WGS 84 - Geographic

EDIT 2:

  • large picture, same CRS for points & baseline map:

enter image description here

  • small picture, same CRS for points & baseline map:

enter image description here

Recology
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    Where did you get the (red) data points? You can try different projections or projection parameters, but going to the source seems to be the obvious thing to do – Robert Hijmans May 14 '21 at 01:19
  • The data comes from a csv file that my research supervisor gave me. I have edited my message to add a screenshot of the raw data. – Recology May 14 '21 at 08:51
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    Then you should ask them what it is or where they got it. It clearly is not ESPG:4326 – Robert Hijmans May 14 '21 at 14:41
  • Ok thanks. But still, I have tried to transform the data frame into a spatialdataframe and then I have set the same CRS as for the baseline. And when I plot the points and the baseline (same crs) I still have a shift. And if I try to plot the map, enlarge it, **and then** project the points, I obtain strange shifts. But when the picture is set to the minimal size, it seems to reduce the shift (make it disappear?) - see second edit of my question. So my question is: could this just be an artifact from the R representation tool? – Recology May 14 '21 at 17:15
  • Does it work if first resize the image area and then plot the raster and points again? – Robert Hijmans May 14 '21 at 19:51
  • Sorry @Robert Hijmans, but how would you resize the image area? I have tried different things but nothing works better. – Recology May 15 '21 at 10:58
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    This seems to be a long running issue with overlapping data on raster plots: https://stackoverflow.com/questions/24213453/overlay-raster-plot-using-plot-add-t-leads-to-arbitrary-misalignment-of-fin – Lucas Fortini May 19 '21 at 17:32
  • @LucasFortini Many thanks, greatly appreciated! I had not found this question when I researched for an answer :-) – Recology May 19 '21 at 18:53

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