Figure 10 shows the basic configuration of objects that prevent melting and refreezing mal-
functions in Object-GAWSER. REFREZP and KF calculate the amount of liquid water in the snow-
pack that refreezes. KMa and MELTP calculate the amount of solid water in the snowpack that melts
and becomes liquid water. TBAS, TEMPs, and TEMPSWITCH are used to simulate both refreezing
of liquid water and the melting of solid water in the snowpack.
Density/Depth section
The Density/Depth section calculates the density and depth of the snowpack. The depth is calcu-
lated as a function of new snow additions, snowmelt and compaction. The density is calculated as a
function of the snow depth and the solid water content of the snowpack. Every element in the Dens-
ity/Depth section is shown Figure 11.
SDEP
COMPACTION
SNOW IN
DSNOW
SNOWMELT
MELT II
COMPAC CALC
MELT I
RHO
TRHO II
KC
MRHO
TRHO DEL
SWC
TRHO I
~
DSNOW
B
A
TEMPs
TRHO I IN
TRHO I OUT
Figure 11. The Density/Depth section. This section is divided into
two sections. The objects in the top half of the diagram are used to
calculate the depth of the snowpack. The objects in the bottom half of
the diagram calculate the density of the snowpack. RHO is used to
calculate both the density and the depth of the snowpack. The dividing
line between the top and bottom halves is used here for clarification
and is not found in the actual object-model.
The depth of the snowpack is calculated by the objects in the top half to Figure 11. The density
of the snowpack is calculated by the objects in the bottom half of Figure 11. RHO, which lies in the
top half of Figure 11, is used to calculate both the density and the depth of the snowpack.
The initial conditions for all the variables within the Basic Density/Depth section except COM-
PACTION, COMPAC_CALC, KC, MELT_I, MELT_II, RHO, SNOW_IN, SNOWMELT,
TRHO_II_IN, TRHO_II_ OUT, and TRHO_DEL are identical to those from a simulation prepared
by Schroeter (1989). COMPACTION, SNOW_IN, SNOWMELT, TRHO_II_IN, are
TRHO_II_OUT are initially zero because they are calculated at the end of every time interval. The
name, a brief description, the initial condition, and the units of each variable featured in this section
are listed in Table 4.
The following equations are used to calculate the depth of the snowpack. As shown in Figure 11,
SDEP is incremented by SNOW_IN and decremented by COMPACTION and SNOWMELT.
SNOW_IN uses the value in DSNOW, COMPACTION uses the value of COMPAC_ CALC, and
SNOWMELT is the sum of MELT_I and MELT_II (from Fig. 9) divided by RHO:
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