c$Author: fredfox $
c$Date: 2001-09-27 22:06:24 $
c$Revision: 1.2 $
c$Source: /weru/cvs/weps/weps.src/inc/hydro/dvolwparam.inc,v $
c     defines for soil water properties
c     number of layers plus six variables
c     ponded depth, cumulative evaporation, cumulative runoff,
c     cumulative infiltration, cumulative drainage,
c     and cumulative rainfall
c     iwork and rwork arrays set for max 100 soil layers
c     plus 6 auxilary variables (neq = 106, ml=3, mu=1)
c     lrw = 22 + 10*NEQ + (2*ML+MU)*NEQ   if JT = 4 or 5.
c     liw = 20 + NEQ
      integer  lrw, liw
      parameter (liw = 126)
      parameter (lrw = 1824)
      integer layrsn, istate, iwork(liw)
      real*4 t, rwork(lrw), tlay(mnsz),dist(mnsz),depth(mnsz),
     &       thetas(mnsz), thetar(mnsz), ksat(mnsz),
     &       airentry(mnsz), lambda(mnsz),
     &       theta80rh(mnsz), thetaw(mnsz),
     &       soiltemp(mnsz),
     &       airtmaxprev, airtmin, airtmax, airtminnext, tdew,
     &       beginday, lenday, sunrise, sunset,
     &       evapamp, raindepth, rainstart, rainend, rainmid,
     &       soilslope, pondmax, dw_friction, slopelength,
     &       atmpres,
     &       lastvolw(mnsz+7), cond(mnsz), swm(mnsz),
     &       soilrh(mnsz), soilvapden(mnsz), soildiffu(mnsz),
     &       prevvolw(mnsz+7)


      common / dvolwparam /
     i layrsn, istate, iwork,
     r t, rwork, tlay, dist, depth,
     r thetas, thetar, ksat,
     r airentry, lambda,
     r theta80rh, thetaw,
     r soiltemp,
     r airtmaxprev, airtmin, airtmax, airtminnext, tdew,
     i beginday, lenday, sunrise, sunset,
     r evapamp, raindepth, rainstart, rainend, rainmid,
     r soilslope, pondmax, dw_friction, slopelength,
     r atmpres,
     r lastvolw, cond, swm,
     r soilrh, soilvapden, soildiffu,
     r prevvolw


c     lrw             - lsoda: length of real work array
c     liw             - lsoda: length of integer work array
c     layrsn          - number of soil layers
c     istate          - LSODA input control and result flag, preserved between days
c     iwork(20+numeq) -  lsoda: integer work array
c     t               - time since last LSODA initialization, preserved between days
c     rwork(22+10*numeq+(2*ml+mu)*numeq - lsoda: real work array
c     tlay(mnsz)      - soil layer thickness (m)
c     dist(mnsz)      - distance from center of soil layer(index-1)
c                       to soil layer(index) (m)
c     depth(mnsz)     - distance from surface to center of soil layer (m)
c     thetas(mnsz)    - saturated volumetric water content
c     thetar(mnsz)    - volumetric water content where conductivity ceases (residual)
c     ksat(mnsz)      - saturated hydraulic conductivity (m/s)
c     airentry(mnsz)  - Brooks and Corey air entry potential (m)
c     lambda(mnsz)    - Brooks and Corey pore interaction exponent
c     theta80rh(mnsz) - volumetric water content when soil air is 80 percent
c                       relative humidity (obtained from soil adsorption isotherm estimates)
c     thetaw(mnsz)    - wilting point (15 bar) volumetric water content
c     soiltemp(mnsz)  - soil temperature (C)
c     airtmaxprev     - maximum air temperature of the previous day (C)
c     airtmin         - minimum air temperature today (C)
c     airtmax         - maximum air temperature today (C)
c     airtminnext     - minimum air temperature of the next day (C)
c     tdew            - dewpoint temperature (C)
c     beginday        - time of the beginning of the day (seconds)
c     lenday          - length of the daylight (seconds)
c     sunrise         - time of sunrise (seconds)
c     sunset          - time of sunset (seconds)
c     evapamp         - amplitude of the daily evaporation curve (m)
c                       calculated from pi*dailydepth(m)/lenday/2.0
c     raindepth       - total depth of a rainfall event (m)
c     rainstart       - time of the start of a rainfall event (seconds)
c     rainend         - time of the end of a rainfall event (seconds)
c     rainmid         - time of the peak of a rainfall event (seconds)
c     soilslope       - slope of the soil surface (m/m)
c     pondmax         - maximum depth of soil surface ponding before runoff (m)
c     dw_friction     - darcy weisbach friction factor for runoff flow rate calculation
c     slopelength     - length of sheet flow runoff (overland flow element)
c     atmpres         - pressure of the ambient atmosphere (kPa)
c     lastvolw(mnsz+6) - value saved from previous entry into dvolw
c     cond(mnsz)      - value used from previous entry into dvolw
c     swm(mnsz)       - value used from previous entry into dvolw
c     soilrh(mnsz)    - value used from previous entry into dvolw
c     soilvapden(mnsz) - value used from previous entry into dvolw
c     soildiffu(mnsz) - value used from previous entry into dvolw
c     prevvolw(numeq) - initial values of water content at beginning of hour
c                       indexes greater than layrsn may be updated hourly