Read short wave radiation, interpolate in time

INTERFACE:

    subroutine read_swr(jul,secs,swr)

DESCRIPTION:

This routine reads the short wave radiation (in Ws$^{-2}$) from swr_file and interpolates in time.

USES:

    IMPLICIT NONE

INPUT PARAMETERS:

    integer, intent(in)                 :: jul,secs

OUTPUT PARAMETERS:

    REALTYPE,intent(out)                :: swr

REVISION HISTORY:

    Original author(s): Karsten Bolding
    See log for airsea module