# this code simulates some random data on a 2d lat/lon # grid and puts them into a data frame set.seed(456) mat = matrix(0, 360, 181) mat[1:5, 1:5] = rnorm(25) + 1i * rnorm(25) mat = Re(fft(mat, inverse=TRUE)) dat = crossing(Latitude = -90:90, Longitude = -179:180) %>% mutate(data = c(mat)) # load coast lines from Rnaturalearth package and # convert to tidy data frame coast = ne_coastline(scale = 'medium') %>% fortify # plot data and overlay add coastline ggplot(dat) + geom_raster(aes(x=Longitude, y=Latitude, fill=data), show.legend=FALSE) + geom_path(data=coast, aes(x=long, y=lat, group=group), colour='white') + scale_fill_viridis_c()
