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I am trying to reproject a raster from Cylindrical Equal-Area (Lambert). Central Meridian: -160. Datum: WGS 1984 to latitude and longitude But I'm getting multiple error messages. The original raster looks like this when plotted with rasterVis: enter image description here

My code is as follows:

library(raster)
#read raster
raster(r)

# Define new Proj.4 spatial reference 
sr <- "+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0"

# Project Raster
projected_raster <- projectRaster(r, crs = sr)

#But I get the following errors: 
Error in if (maxy == miny) { : missing value where TRUE/FALSE needed
In addition: Warning message:
In rgdal::rawTransform(projfrom, projto, nrow(xy), xy[, 1], xy[,  :
53 projected point(s) not finite

I am not sure whether this is a problem with the raster or my code? Please help!

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  • Try CRS in your code: sr <- CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0")
    – Guz
    Commented Dec 7, 2016 at 14:43
  • Hi Guzman, I tried this and it made no difference.
    – Phoebe Stewart-Sinclair
    Commented Dec 7, 2016 at 15:07
  • Use gdaltransform() from gdalUtils package
    – aldo_tapia
    Commented Dec 7, 2016 at 15:15
  • @PhoebeStewart-Sinclair please try to provide a reproducible example, so we can understand better your question and give a better answer!
    – Guz
    Commented Dec 7, 2016 at 15:40
  • The website this data comes from wri.org/resources/data-sets/reefs-risk-revisited under Global Threats:Data. I want to reproject the basic w001001.adf raster files from Equal-Area (Lambert) to lat/long ("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0") in R
    – Phoebe Stewart-Sinclair
    Commented Dec 7, 2016 at 16:00

1 Answer 1

Reset to default
1

Error probably came from its extent.

library(raster)
r <- raster("C:/GIS/Global_Threats/Acidification/arag_500/w001001.adf")
crs(r) <- "+proj=cea +datum=WGS84 +lon_0=-160.0 +lat_ts=0.0 +x_0=0.0 +y_0=0.0"
r

r returns extent : -20037507, 19962493, -6363885, 6436115 (xmin, xmax, ymin, ymax) so just as a test I have cut y-value (latitude) at 90% to north and south.

extent(r) <- c(xmin= -20037507, xmax= 19962493, ymin= 0.9*(-6363885), ymax= 0.9*(6436115))
sr <- "+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0" 
projected_raster <- projectRaster(r, crs= sr, method = 'bilinear')
plot(projected_raster)

enter image description here

How much you can cut northern/southern edge will depend on your study area.

[EDIT] This discussion will be better and complete answer to your question about what happened. Re-projecting raster in R: gives warning that projected point(s) not finite?

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  • I'm glad it worked out.
    – Kazuhito
    Commented Dec 8, 2016 at 14:52

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