[MITgcm-devel] question regarding seaice_solve4temp.F

[Ian Fenty]

J-M,
I believe you are correct, with the new SVP formulation the check you 
mention is not necessary.

Now, lowering ice surface temperature will always cause a net decrease 
to ice surface heat flux divergence (increased latent, sensible, and 
conductive heat flux convergence and decreased Stefan-Boltzmann 
divergence).

Ergo, the gradient of d(heat flux residual)/d (ice surface temperature) 
should always single-signed and there isn't another solution to the 
energy balance equation at very low ice surface temperatures.

That block of code can (probably) be safely removed!

-Ian




I went through my notes and can't find the example that led me to add 
this check.
On 1/30/2012 10:34 AM, Jean-Michel Campin wrote:
> Hi Ian,
>
> I have a question regarding this part of the code, formerly in
> seaice_budget_ice_if.F and now in seaice_solve4temp.F (non-legacy):
>> c    If the search falls below 50 Kelvin then kick the search back up to
>> c    TMELT.  Note that a solution to the equation is for a large negative
>> c    value of ice surface temperature since the longwave outgoing radiation
>> c    goes as the fourth power of temperature.
>>            IF (tsurfLoc(I,J) .LT. 50.0 ) THEN
>>                 tsurfLoc(I,J) = TMELT
>>    
It seems to me that with the new (SVP), the search for tsurf looks quite 
safe, with always dFiDTs1 > 0. May be I am missing something ? If you 
could provide an example where this problem show-up, it would be nice.