wrfv2_fire/chem/KPP/kpp/kpp-2.1/util/UpdateSun.f90

   1   SUBROUTINE Update_SUN()
   2       !USE KPP_ROOT_Parameters
   3       !USE KPP_ROOT_Global
   4
   5     IMPLICIT NONE
   6
   7     KPP_REAL SunRise, SunSet
   8     KPP_REAL Thour, Tlocal, Ttmp
   9
  10     SunRise = 4.5_dp
  11     SunSet  = 19.5_dp
  12     Thour = TIME/3600.0_dp
  13     Tlocal = Thour - (INT(Thour)/24)*24
  14
  15     IF ((Tlocal>=SunRise).AND.(Tlocal<=SunSet)) THEN
  16        Ttmp = (2.0*Tlocal-SunRise-SunSet)/(SunSet-SunRise)
  17        IF (Ttmp.GT.0) THEN
  18           Ttmp =  Ttmp*Ttmp
  19        ELSE
  20           Ttmp = -Ttmp*Ttmp
  21        END IF
  22        SUN = ( 1.0_dp + COS(PI*Ttmp) )/2.0_dp
  23     ELSE
  24        SUN = 0.0_dp
  25     END IF
  26
  27  END SUBROUTINE Update_SUN
  28