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Release of VIC 4.1.2.d
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@jhamman jhamman released this 20 Aug 19:50
· 2688 commits to master since this release
VIC.4.1.2.d
1887a8f

***** Description of changes from VIC 4.1.2.c to VIC 4.1.2.d *****

Bug Fixes:

Fixed incorrect summing of rain and snow components of precipitation over grid
cell

Files Affected:

full_energy.c

Description:

The amounts of rainfall and snowfall over the lake (or inundated wetland)
were being omitted from the grid cell totals.  This has been fixed.

Vapor pressure incorrect if user supplies (QAIR or REL_HUMID) + PRESSURE as
input forcings instead of vapor pressure.

Files Affected:

initialize_atmos.c

Description:

For the cases of the combination of (QAIR or REL_HUMID) plus PRESSURE
supplied as input forcings instead of VP, the logic distinguishing
between daily and sub-daily supplied PRESSURE was flawed, resulting
in incorrect values in both cases.  This has been fixed.

***** Description of changes from VIC 4.1.2.b to VIC 4.1.2.c *****

Bug Fixes:

Incorrect handling of user-supplied tskc (cloud fraction) for LW_CLOUD==LW_CLOUD_DEARDORFF

Files Affected:

calc_longwave.c
mtclim_vic.c

Description:

Previous versions of VIC (before 4.1.2) used a full-sky longwave
formulation taken from two formulas in the Bras hydrology text.  For
the new Deardorff full-sky longwave formulation, the dependence on
cloud fraction is different from the old Bras formulation.   In 
4.1.2 (and 4.1.2.a-b), the new Deardorff formulation did not account
for the possibility of user-supplied cloud fraction; if the user
supplied cloud fraction as an input forcing, the resulting longwave
was wrong.  This has been fixed.

Changed default settings of MTCLIM_SWE_CORR and LW_TYPE to reflect best
general settings

Files Affected:

initialize_global.c
global.param.sample

Description:

In light of the findings of Bohn et al. (2012), we have changed the
default setting of MTCLIM_SWE_CORR to FALSE and of LW_TYPE to
LW_PRATA.  These settings give forcing estimates that are less biased
in general.

Vapor pressure set to 0 if user supplies (QAIR or REL_HUMID) + PRESSURE as
input forcings instead of vapor pressure.

Files Affected:

initialize_atmos.c

Description:

For the cases of the combination of (QAIR or REL_HUMID) plus PRESSURE
supplied as input forcings instead of VP, VIC was supposed to compute
VP from (QAIR or REL_HUMID) and PRESSURE, then transfer the computed
VP to the atmos data structure.  This transfer was being skipped, and
vapor pressure was consequently set to 0 during the simulation.  This
has been fixed.

Computed longwave sometimes is extremely large at high latitudes.

Files Affected:

mtclim_vic.c

Description:

Previously (VIC 4.1.2, 4.1.2.a, and 4.1.2.b only), when SHORTWAVE and
VP were supplied to VIC as input forcings (and LONGWAVE was NOT
supplied as a forcing), the incoming longwave radiation computed by
VIC would in rare cases become extremely large.  This happens only at
high latitudes in winter when the theoretical clear-sky potential
solar radiation is very small.  If the supplied VP was large enough,
it could cause the internal variable t_tmax (clear-sky transmittance)
to go negative.  This in turn would cause the internal variable
t_fmax (cloud transmittance) to go negative as well.  This, finally,
would cause computed LONGWAVE values to become extremely large, if
the LW_CLOUD method was set to DEARDORFF.  This has been fixed.

***** Description of changes from VIC 4.1.2.a to VIC 4.1.2.b *****

Bug Fixes:

VIC was unnecessarily requiring WIND to be supplied as an input forcing.

Files Affected:

initialize_atmos.c
vicNl_def.h

Description:

VIC was requiring WIND (or the zonal and meridional components of
wind, WIND_E and WIND_N) to be supplied as an input forcing.  Now VIC
allows WIND to be omitted.  If WIND is not supplied as an input
forcing, VIC will supply a default wind speed, defined in vicNl_def.h
as DEFAULT_WIND_SPEED and currently set to 3.0 m/s.

Cloud fraction tskc was not accounting for the case in which observed incoming
shortwave is supplied as a forcing.

Files Affected:

mtclim_vic.c

Description:

In the absence of observations, VIC's estimate of cloud fraction, tskc,
is a function of some intermediate quantities that are computed within
the MTCLIM algorithm (in mtclim_vic.c).  These intermediate terms
can be computed from either observed daily shortwave radiation (if
available) or simulated daily shortwave radiation.  The computation
of tskc was previously taking place in a part of the code where
only the simulated daily shortwave radiation was available.  Thus,
tskc would not reflect the actual amount of incident shortwave, even
if observed incident shortwave was supplied as a forcing.

This has been fixed.  The tskc computation has been moved to another
location in the code where the observed daily shortwave can be
accessed (if supplied by the user as a forcing).
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