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Changes to Noah LSM version 3.2 since version 3.1
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   * Z0 for snow cover

       - Roughness length Z0 over snow-covered surfaces has been modified
         (subroutine SNOWZ0) to account for the accumulation of snow
         burying the surface features which contribute to roughness.

         An "effective" roughness length for the snow-covered surface is
         computed, Z0EFF.  For deep snow, Z0EFF is set to 0.001 (deep snow
         covering the roughness features of the surface).  For shallower
         snow, Z0EFF is set to the snow-free roughness length, Z0BRD,
         reduced by SNOWH/7.

         To account for fractional snow cover, the final Z0 term is
         computed as a weighted average between the snow-free Z0BRD value
         and the effective snow albedo, Z0EFF.

   * LVCOEF:

       - The surface albedo in the presence of snowcover (subroutine
         ALCALC) is computed following Livneh.  In version 3.2, this has
         been implemented with a user-definable coefficient, LVCOEF, set
         in file GENPARM.TBL.  LVCOEF should range between zero and one.

         The Livneh scheme boosts the snow albedo toward 85%, then reduces
         it according to the age of the snow.  LVCOEF controls how much
         the albedo is boosted toward 85%.  A default value LVCOEF=0.5
         will have the same results as in version 3.1, i.e., an average of
         the input SNOALB (which tends to range from around 50% to around
         75%) and 85%.  Values lower than 0.5 will tune this more toward
         the incoming SNOALB (and ultimately lower albedos).  Values
         greater than 0.5 will tune this more toward 85% (and ultimately
         higher albedos).

   * SMAV:

       - SMAV: Soil moisture availability at each soil layer, computed as a
         fraction between the wilting point SMCWLT (SMAV=0.0) and
         saturation soil moisture SMCMAX (SMAV=1.0).  No effect on model
         results.  Diagnostic field output in WRF as "SMCREL: Relative soil
         moisture".

   * FLX1:

       - The FLX1 term needs to account for the exchange of heat required
         to change the temperature of falling precipitation from air
         temperature to skin temperature.  This exchange is considered in
         computing fluxes and skin temperature, but for rain events, was
         not included in the budget term FLX1.  So the energy budget would
         show large residual values for rain events.  This correction has
         no effect on the model integration, but will make the budget
         calculations which use FLX1 more accurate.

   * DTOT:

       - Polar modification: over sea/land ice points, DTOT is limited so
         as not to effectively shut off heat exchange between soil (i.e.,
         ice) layers and the surface.  In SNOPAC, this limit was applied
         regardless of surface type (ice or land).  In Version 3.2, this
         has been corrected to apply only to sea/land ice points.  Could
         have some effect on results in areas of deep snow.

   * RC:

       - Canopy Resistance, RC, normally set in the call to subroutine
         CANRES, is set to zero if CANRES is not called because SHDFAC is
         0.  This change should have no effect on model integration, but
         since RC is an output variable, this change insures that the field
         is initialized where there is no vegetation.  This was not an
         issue for Noah as coupled to WRF, but was causing troubles in some
         standalone applications of Noah LSM.