_RL  dhi           ! change in ice thickness

         dhi = -ebot / (qbot * rhoi)

         qicen(k) = (hnew(k)*qicen(k)+dhi*qbot) / (hnew(k)+dhi)

         hnew(k) = hnew(k) + dhi

               dhi = evap/rhoi*dt 

               if (dhi.ge.hnew(k)) then

                 hq = hnew(k)*qicen(k)-dhi*Lfresh

                 hnew(k) = hnew(k) - dhi

         dhi = (hs * rhos - hi * rhoiw) / rhosw

         dhs = dhi * rhoi / rhos

         hnew(1) = hnew(1) + dhi

         hi = hi + dhi