!     file: cenvr.inc

!     This file contains the declaration of the common block of variables
!     related to the weather data and temperature factors.

!     + + + VARIABLE DECLARATIONS + + +
!      real tmx,tmn,r,ra,rh,tav,vpd,tava,hrlt,hrlty,hlmn0,
       real vpd,tava,hrlt,hrlty,hlmn0,                                  &
     & shu,dhu,hui,dhuf,huf,hufy,ehu,tplant,frst,fhr,                   &
     & ts,hu,xlat,cta,ceta,ctab,cetab,ctas,cetas,ctay,cetay,prcp,       &
     & prcpb,prcpy,prcps,ctp,ctpb,ctpy,ctps, frs1, frs2,phu
      integer jda,jd

!      common / envr /tmx,tmn,r,ra,rh,tav,vpd,tava,hrlt,hrlty,
       common / envr / vpd,tava,hrlt,hrlty,                             &
     & hlmn0,shu,dhu,hui,dhuf,huf,hufy,jda,jd,ehu,frs1,frs2,            &
     & tplant,frst,fhr,ts,hu,xlat,cta,ceta,ctab,cetab,ctas,cetas,       &
     & ctay,cetay,prcp,prcpb,prcpy,prcps,ctp,ctpb,ctpy,ctps,phu

!     + + + VARIABLE DEFINITIONS + + +
!    cta - actual cummulated transpiration (mm)
!    ctab - periodic actual cummulated transpiration (mm) on day i
!    ctay - periodic actual cummulated transpiration (mm) on day i-1
!    ctas - seasonal actual cummulated transpiration  (mm)
!    ctp - potential cummulated transpiration (mm)
!    ctpb - periodic potential cummulated transpiration (mm)on day i
!    ctay - periodic potential cummulated transpiration (mm)on day i-1
!    ctas - seasonal potential cummulated transpiration  (mm)
!    ceta - actual cummulated evapotranspiration (mm)
!    cetab - periodic actual cummulated evapotranspiration (mm)on day i
!    cetay - periodic actual cummulated evapotranspiration (mm)on day i-1
!    cetas - seasonal actual cummulated evapotranspiration (mm)
!    dhu - daily heat units (deg. c)
!    dhuf - daily heat unit factor
!    ehu - heat units required from planting seedling emergence
!    frs1 - lower temperature threshold for frost damage (deg. C)
!    frs2 - upper temperature threshold for frost damage (deg. C)
!    frst - frost damage factor
!    fhr - reduction due to day length factor
!    hrlt - day length on day i (h)
!    hrlty - day length on day (i-1)
!    hlmn0 - minimum length of day for a location plus 1 hour
!    hui - heat unit index (ratio of shu to phu)
!    hui0 - heat unit index when leaf senescence starts.
!    huf - heat unit factor for driving leaf-area-index development
!    hufy - value of huf on day (i-1)
!    jda - date of sowing (same as day simulation begins)
!    jd - today's julian date calander
!    phu - potential heat units for crop maturity (deg. c)
!    prcp - cummulated precipitation (mm)
!    prcpb - periodic cummulated precipitation (mm)
!    prcpy - previous value of prcpb (mm)
!    prcps - season cummulated precipitation (mm)
!    r - daily precipitation (mm/day)
!    ra - solar radiation (mj/day)
!    rh - relative humidity (ratio)
!    shu - cummulated heat units ( deg. c)
!    tmn - manimum air temperature (deg. c)
!    tbas - base temperature (deg. c)
!    tmx - maximum air temperature (deg. c)
!    topt - optimum temperature (deg. c)
!    tplant - minimum soil temperature for planting (c)
!    ts - temperature stress factor
!    vpd - vapor pressure deficit (kpa)
!    xlat - latitude of a location (deg.)