! source file: /Users/jfidler/work/UVic_ESCM/2.9/source/ice/cpts.h
!======================= include file "cpts.h" =========================

      integer ncat           ! ice categories (not counting open water)
      integer ntilay         ! equal to the sum of the elements of nilay
      parameter(ncat=1)
      parameter(ntilay=4)
      integer itme           ! number of time levels kept
      parameter(itme = 2)

!     upper limit on the number of layers in a single category
!     fine if bigger than necessary
      integer nmax
      parameter (nmax=10)

!     these common blocks must be initialized at setup, see setembm.F

      real dtau  ! time step (2*dtatm=>leapfrog, dtatm=>forward)
      common/tstep/dtau

      integer idx            ! index for time step
      common/counters/idx

      real M_def  !     area frac from cat i that goes into j
      real N_def  !   volume frac from cat i that goes into j
      real HN_def ! H*volume frac from cat i that goes into j
      common /defmat/ M_def(ncat,ncat), N_def(ncat,ncat)
      common /defmat/ HN_def(ncat,ncat)

      integer nilay      ! the number of layers
      integer layer1     ! position of the top layer
      integer layern     ! position of the bottom layer
      integer ncrel      ! helps remap layers when ridging
      common /layinf/ nilay(ncat), layer1(ncat), layern(ncat)
      common /layinf/ ncrel(ncat,ncat)

      real hstar  ! category limits (m)
      real asmall ! minimum fract. area of allowed
      common /small/ asmall(0:ncat), hstar(0:ncat)

      real saltz   ! salinity of each layer (ppm)
      real tmelz   ! melting temperature of each layer (C)
      real salnew  ! salinity of new ice
      common /salt/ saltz(nmax+1,ncat), tmelz(nmax,ncat), salnew

!     default units are mks so use these factors to
!     convert various parameters from mks to cgs
!     set them equal to 1. if no conversion is desired
      real deci  ! factor of 10.
      real centi ! factor of 100.
      real kilo  ! factor of 1000.

      parameter ( deci=10., centi=100.0, kilo=1000.)
!      parameter ( deci = 1.,  centi = 1.,    kilo = 1.)

!     parameter for small things
      real TINY
      parameter( TINY=1.0e-10 )

!     if open water area > GSTAR then no mechanical redist.
      real GSTAR                   ! portion of itd that may partic.
      parameter ( GSTAR = 0.15 )

!     max ridged ice thickness is 2*sqrt(cK*Hi), Hi is orig thickness
      real cK  ! used to determine max. ridged thickness (m)
      parameter ( cK = 1.e2*centi)

!     if using Rothrock75 energetics argument for pressure
      real cpe ! coef. for potential energy term(N/m**3)
      parameter ( cpe = 450./deci)

!     minimum allowable open water/ice fraction
!     best if small as possible, can cause round off error if too small
      real a0small
      real aismall
      parameter ( a0small=0.0001, aismall=0.0005 )

!     minimum snow thickness allowed
      real hsstar
      parameter ( hsstar=0.00001*centi )