I have a raster from which I need to extract values at point locations using
The raster is at 30 arc-second resolution and came from WorldClim with proj4string:
"+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0"
i.e. it's coordinates are geographic on an ellipsoid. My point location data has the same lon-lat WGS84 CRS.
I've noticed that about 3/4 of the values I extract differ depending on whether or not I've transformed both the raster and the points to a planar projection with proj4string:
"+proj=laea +lat_0=43.15268 +lon_0=-70.30744 +x_0=12019341.4 +y_0=1730136 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs".
My question is, should I expect points to move between raster cells this much as a result of projection? And which method is more accurate? In case spatial scale matters, the bounding box for the points is:
xmin ymin xmax ymax -73.68631 41.01861 -67.89930 45.23919
Please let me know in the comments if this question needs a reproducible example.