!$Author$
!$Date$
!$Revision$
!$HeadURL$

!     This common block contains the state variables relating to
!     the daily hydrologic parameters.

!     Parameter include files:

!     + + + VARIABLE DECLARATIONS + + +

      real             ahrwc(mnsz,mnsub)
      real             ahrwcdmx(mnsz,mnsub)
      real             aheaep(mnsz,mnsub)
      real             ah0cb(mnsz,mnsub)
      real             ahrsk(mnsz,mnsub)
      real             ahfwsf(mnsub)
      real             ahzsno(mnsub)
      real             ahtsno(mnsub)
      real             ahfsnfrz(mnsub)
      real             ahzirr(mnsub)
      real             ahzdmaxirr(mnsub)
      real             ahratirr(mnsub)
      real             ahdurirr(mnsub)
      real             ahlocirr(mnsub)
      real             ahminirr(mnsub)
      integer          am0monirr(mnsub)
      real             ahmadirr(mnsub)
      integer          ahndayirr(mnsub)
      integer          ahmintirr(mnsub)
      real             ahzoutflow(mnsub)
      real             ahzper(mnsub)
      real             ahzrun(mnsub)
      real             ahzinf(mnsub)
      real             ahzsmt(mnsub)
      real             ahzwid(mnsub)
      real             ahzeasurf(mnsub)

!      real             ahrwc0(mnsz,mnsub)

      common / h1hydro /                                                &
     &                  ahrwc, ahrwcdmx, aheaep, ah0cb, ahrsk, ahfwsf,  &
     &                  ahzsno, ahtsno, ahfsnfrz,                       &
     &                  ahzirr, ahzdmaxirr, ahratirr, ahdurirr,         &
     &                  ahlocirr, ahminirr, am0monirr, ahmadirr,        &
     &                  ahndayirr, ahmintirr, ahzoutflow,               &
     &                  ahzper, ahzrun, ahzinf,                         &
     &                  ahzsmt, ahzwid, ahzeasurf
  
!     + + + VARIABLE DEFINITIONS + + +

!     ahrwc  - Soil water content (Kg/Kg)
!     ahrwcdmx - daily maximum soil water content (Kg/Kg)
!     aheaep - Soil air entry potential (J/kg)
!     ah0cb  - Power of Brooks and Corey water release curve model (unitless)
!     ahrsk  - Saturated soil hydraulic conductivity (m/s)
!     ahfwsf - Crop growth water stress factor (unitless)
!     ahzsno - Water content of snow (mm)
!     ahtsno - temperature of snow layer (C)
!     ahfsnfrz - fraction of snow layer water content which is frozen
!     ahzirr - Single day irrigation water applied (mm)
!     ahzdmaxirr - characteristic maximum irrigation system application depth (mm)
!     ahratirr - characteristic irrigation system application rate (mm/hour)
!     ahdurirr - duration of irrigation water application (hours) 
!                corresponding to the characteristic maximum irrigation
!                system application depth. This is used to set the rate (depth / duration)
!     ahlocirr - emitter location point (mm)
!                positive is above the soil surface
!                negative is below the soil surface
!     ahminirr - minimum irrigation application amount (mm)
!     am0monirr - flag setting monitoring for irrigation need
!                 0 - do not monitor irrigation need
!                 1 - monitor irrigation need
!     ahmadirr - management allowed depletion used in monitoring irrigation
!                0.0 sets up replacing yesterdays water loss today
!                1.0 schedules next application at wilting point
!     ahndayirr - the next simulation day on which an irrigation can occur (day)
!     ahmintirr - minimum interval for irrigation application (days)
!     ahzoutflow - height of runoff outlet above field surface (m)
!     ahzper - daily deep percolation (mm/day)
!     ahzrun - daily surface runoff (mm/day)
!     ahzinf - daily surface infiltration
!     ahzsmt - Snow melt (mm)
!     ahzwid - Water infiltration depth (mm)
!     ahzeasurf - accumulated surface evaporation since last complete rewetting (mm)