anchor.diff:                                      ! NOTE, ice = 2110 (J/kg/K), steam = 2080 (J/kg/K)
       real, parameter :: LH_liquid = 3.34E5 ! J/kg
       real, parameter :: heat_capacity = 1006.0 ! air heat capacity J/kg/K
  -    real, parameter :: SMALL_VALUE = 1E-15
  +    real, parameter :: SMALL_VALUE = 1E-30
       real, parameter :: SMALL_PRESSURE = 1000. ! in Pa this is actually pretty small...
   !     real, parameter :: mp_R = 287.058 ! J/(kg K) specific gas constant for air
   !     real, parameter :: mp_g = 9.81 ! gravity m/s^2
  
positive.code:             if (qv<qvsat) then
                  if (qr>SMALL_VALUE) then
                      ! evaporate rain
                      call phase_change(pressure,temperature,qr,qvsat,qv,L_evap,1.0) !cloud2rain)
                  endif
                  if (qs>SMALL_VALUE) then
                      ! sublimate snow
                      call phase_change(pressure,temperature,qs,qvsat,qv,L_subl,1.0) !cloud2snow)
                  endif
              endif
          endif
  
negative.code:                 excess = excess*(-1) !DEBUG
              endif
          enddo
          if (iteration==15) then
              qv = sat_mr(pre_t,pressure)
              temperature = pre_t
              qc = pre_qc
          endif
  
          qc = max(qc,0.)
  
  