[esp-r] Re: Result message - question - Rabenseifer

[Jon Hand (clcv10)]

A recent question about MZELWE warnings during a simulation....
  e.g. MZELWE a dubious sky temperature has been calculated
  e.g. MZELWE a longwave flux of 518 W has been calculated for  
Surf-9:House_Z


Such warnings happens as a result of a combination of factors
a) the composition of the roof (typically when there is metal with  
insulation
below it, b) an angled roof, c) specific climate patterns (low  
humidity or
a climate file with slightly unreal temperature and humidity  
conditions).

The result of this combination is an over-estimation of heat losses
from the surface and a warning is given.  If this happens 20 or 50
times then it is an issue. In your case it only happened for a few  
timesteps
so it is not an issue.

The warning about dubious sky temperature might just be a glitch in the
climate file at one or two timesteps.  The temperature of the sky is  
derived
from the temperature and humidity (there are several different  
options, but
the default usually works ok). If this message only happens a few  
times then
it probably is not an issue. If it happens a lot then you might want  
to choose
a different climate or check the details of the current climate file.

-ESRU