r - Projection error with autoKrige function -

i have problem autokrig function , try make reproducible example here:

library(automap) library(raster) library(dismo)  bio <- getdata("worldclim", var="bio", res=10)  bio1 <- raster(bio, layer=1) bio12 <- raster(bio, layer=12) predictors <- stack(bio1, bio12)  bg <- randompoints(bio1, 50)  data <- extract(predictors, bg) data <- cbind(bg,data) data <- data.frame(data)  coordinates(data)=~x+y proj4string(data) = crs("+proj=longlat +datum=wgs84 +ellps=wgs84 +towgs84=0,0,0") kg <- autokrige(bio1~bio12, data, new_data=predictors) 

this result in:

error in autokrige(bio1 ~ bio12, data, new_data = predictors) :    either input_data or new_data in longlat, please reproject.    input_data:  +proj=longlat +datum=wgs84 +ellps=wgs84 +towgs84=0,0,0     new_data:    +proj=longlat +datum=wgs84 +ellps=wgs84 +towgs84=0,0,0  

i same error original data. appreciate help.

if read file, tell why throwing error.

autokrige performs checks on coordinate systems of input_data , new_data. if 1 or both na, assigned projection of other. if have different projections, error raised. if 1 or both has non-projected system (i.e. latitude-longitude), error raised. error raised because 'gstat use spherical distances when data in geographical coordinates, usual variogram models typically not non-negative definite on sphere, , no appropriate models available' (edzer pebesma on r-sig-geo).

it looks need project data before calling autokrige.