Differences between T_S, T_G and T_SNOW – in #14: CCLMCLM
in #14: CCLMCLM
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<p>
Dear
<span class="caps">
CCLM
</span>

<span class="caps">
CLM
</span>
users,
<br/>
Our group has recently developed a fullycoupled icesheet – ocean seaice – atmosphere – land model involving
<span class="caps">
CCLM
</span>
_CLM. Our configuration covers the Antarctic. I would like to know what are the differences between the following variables outputted by
<span class="caps">
COSMO
</span>
: T_S (temperature of surface), T_G (temperature at the boundary soilatmosphere) and T_SNOW (temperature of snow surface). I did not find in the documentation how they are computed. I observe that T_S and T_G provide identical temperatures over the continental ice, but it is not true over the ocean (especially over the sea ice). I am also surprised to see differences up to 20°C in absolute value between T_S and T_SNOW (at most places, the surface is fully covered by snow).
<br/>
Thank you very much for your input,
<br/>
Sylvain
</p>
<p>
Dear
<span class="caps">
CCLM
</span>

<span class="caps">
CLM
</span>
users,
<br/>
Our group has recently developed a fullycoupled icesheet – ocean seaice – atmosphere – land model involving
<span class="caps">
CCLM
</span>
_CLM. Our configuration covers the Antarctic. I would like to know what are the differences between the following variables outputted by
<span class="caps">
COSMO
</span>
: T_S (temperature of surface), T_G (temperature at the boundary soilatmosphere) and T_SNOW (temperature of snow surface). I did not find in the documentation how they are computed. I observe that T_S and T_G provide identical temperatures over the continental ice, but it is not true over the ocean (especially over the sea ice). I am also surprised to see differences up to 20°C in absolute value between T_S and T_SNOW (at most places, the surface is fully covered by snow).
<br/>
Thank you very much for your input,
<br/>
Sylvain
</p>
Dear
CCLM

CLM
users,
Our group has recently developed a fullycoupled icesheet – ocean seaice – atmosphere – land model involving
CCLM
_CLM. Our configuration covers the Antarctic. I would like to know what are the differences between the following variables outputted by
COSMO
: T_S (temperature of surface), T_G (temperature at the boundary soilatmosphere) and T_SNOW (temperature of snow surface). I did not find in the documentation how they are computed. I observe that T_S and T_G provide identical temperatures over the continental ice, but it is not true over the ocean (especially over the sea ice). I am also surprised to see differences up to 20°C in absolute value between T_S and T_SNOW (at most places, the surface is fully covered by snow).
Thank you very much for your input,
Sylvain
<p>
I do not use the coupled version ans therefore have no experience how the parameters behave there. In the uncoupled version there is a sketch in the subroutine src_soil_multlay.f90:
</p>
<pre>
! Definition of temperature/water related variables in the soil model
!
!
! T_snow
! 
! fr_snow  1  fr_snow
! 
! ______________T_s__________________________T_s_____________
! ////////////////////////////////////////////////////////////
!
! Layer k=1      T_SO(k) , W_SO(k), W_SO_ICE(k)    
!
! ____________________________________________________________
!
! .
! .
! .
!
! 
!
!
! Layer k=ke_soil+1    (climate layer)          
!
!
! ____________________________________________________________
!
!
!
! The surface temperature T_g is the snow fraction (fr_snow)
! weighted sum of T_snow and T_s!
!==============================================================================
</pre>
<p>
I do not use the coupled version ans therefore have no experience how the parameters behave there. In the uncoupled version there is a sketch in the subroutine src_soil_multlay.f90:
</p>
<pre>
! Definition of temperature/water related variables in the soil model
!
!
! T_snow
! 
! fr_snow  1  fr_snow
! 
! ______________T_s__________________________T_s_____________
! ////////////////////////////////////////////////////////////
!
! Layer k=1      T_SO(k) , W_SO(k), W_SO_ICE(k)    
!
! ____________________________________________________________
!
! .
! .
! .
!
! 
!
!
! Layer k=ke_soil+1    (climate layer)          
!
!
! ____________________________________________________________
!
!
!
! The surface temperature T_g is the snow fraction (fr_snow)
! weighted sum of T_snow and T_s!
!==============================================================================
</pre>
I do not use the coupled version ans therefore have no experience how the parameters behave there. In the uncoupled version there is a sketch in the subroutine src_soil_multlay.f90:
! Definition of temperature/water related variables in the soil model
!
!
! T_snow
! 
! fr_snow  1  fr_snow
! 
! ______________T_s__________________________T_s_____________
! ////////////////////////////////////////////////////////////
!
! Layer k=1      T_SO(k) , W_SO(k), W_SO_ICE(k)    
!
! ____________________________________________________________
!
! .
! .
! .
!
! 
!
!
! Layer k=ke_soil+1    (climate layer)          
!
!
! ____________________________________________________________
!
!
!
! The surface temperature T_g is the snow fraction (fr_snow)
! weighted sum of T_snow and T_s!
!==============================================================================
<p>
Thanks for replying Burkhardt. Given that the surface temperature T_s is the snow fraction weighted sum of T_snow and T_s and that each model cell in Antarctica is almost 100% covered by snow, one can expect T_g to be close to T_s then?
</p>
<p>
Thanks for replying Burkhardt. Given that the surface temperature T_s is the snow fraction weighted sum of T_snow and T_s and that each model cell in Antarctica is almost 100% covered by snow, one can expect T_g to be close to T_s then?
</p>
Thanks for replying Burkhardt. Given that the surface temperature T_s is the snow fraction weighted sum of T_snow and T_s and that each model cell in Antarctica is almost 100% covered by snow, one can expect T_g to be close to T_s then?
<p>
Over areas covered 100% by snow I would expect T_G to be the same as T_SNOW. T_S is the temperature at the earth surface under the snow this can be much different than the temperature at the snow surface T_SNOW.
</p>
<p>
Over areas covered 100% by snow I would expect T_G to be the same as T_SNOW. T_S is the temperature at the earth surface under the snow this can be much different than the temperature at the snow surface T_SNOW.
</p>
Over areas covered 100% by snow I would expect T_G to be the same as T_SNOW. T_S is the temperature at the earth surface under the snow this can be much different than the temperature at the snow surface T_SNOW.
Differences between T_S, T_G and T_SNOW
Dear CCLM  CLM users,
Our group has recently developed a fullycoupled icesheet – ocean seaice – atmosphere – land model involving CCLM _CLM. Our configuration covers the Antarctic. I would like to know what are the differences between the following variables outputted by COSMO : T_S (temperature of surface), T_G (temperature at the boundary soilatmosphere) and T_SNOW (temperature of snow surface). I did not find in the documentation how they are computed. I observe that T_S and T_G provide identical temperatures over the continental ice, but it is not true over the ocean (especially over the sea ice). I am also surprised to see differences up to 20°C in absolute value between T_S and T_SNOW (at most places, the surface is fully covered by snow).
Thank you very much for your input,
Sylvain
I do not use the coupled version ans therefore have no experience how the parameters behave there. In the uncoupled version there is a sketch in the subroutine src_soil_multlay.f90:
Thanks for replying Burkhardt. Given that the surface temperature T_s is the snow fraction weighted sum of T_snow and T_s and that each model cell in Antarctica is almost 100% covered by snow, one can expect T_g to be close to T_s then?
Over areas covered 100% by snow I would expect T_G to be the same as T_SNOW. T_S is the temperature at the earth surface under the snow this can be much different than the temperature at the snow surface T_SNOW.