R/latlon2ucs.R

In steingod/R-osisaf: Useful functions for handling EUMETSAT Ocean and Sea Ice SAF data

latlon2ucs <- function(lat,lon) {
    
    rearth <- 6371.

    deg2rad <- pi/180.

    lattruerad <- 60.*deg2rad

    vr <- (90.+0)*deg2rad

    lat <- lat*deg2rad
    lon <- lon*deg2rad

    distpoleq <- rearth*(1.+sin(lattruerad))

    rr <- distpoleq*cos(lat)/(1.+sin(lat))
    xr <- rr*sin(lon)
    yr <- -rr*cos(lon)

    eastings <- xr*sin(vr)-yr*cos(vr)
    northings <- yr*sin(vr)+xr*cos(vr)

    return(data.frame(northings=northings,eastings=eastings))
}