anchor.diff:  !-----------------------------------------------------------------------
   !
  -! Contains all subroutines to get time-varying mixing ratios of CO2, 
  +! Contains all subroutines to get time-varying mixing ratios of CO2,
   ! N2O, CH4, CFC11 and CFC12 into radiation schemes.
   ! These subroutines enable the user to specify the mixing ratios
   ! in the file CAMtr_volume_mixing_ratio, giving the user an easy way
  
positive.code:     REAL(r8), INTENT (IN)                   :: y1,y2
      REAL(r8), INTENT (OUT)                  :: y
      REAL(r8)                                :: a,b,x
      
      a=y1
      b=(y2-y1)/(x2-x1)
      
      IF (x0 .GE. x1) THEN
         x=x0-x1
      ELSE
         x=x1-x0
         b=-b
      ENDIF
      
      y=a+b*x
      
    END SUBROUTINE interpolate_lin
  
  
  
negative.code:        ENDIF
         iyear=iyear+1
      ENDDO
  
      ! Prevent yr > last year in data
  !    IF (yearIN .ge. VARCAM_in_years) yearIN=VARCAM_in_years-1
      IF (iyear .ge. max_years) then
         yearIN=max_years-1
         found_yearIN = 1
      ENDIF
  
      IF (found_yearIN .NE. 0 ) THEN
         if (yearIN .eq. 1) yearIN = yearIN + 1    ! To take 2 first lines of the file
         nyrm = yrdata(yearIN-1)
  