[MITgcm-support] bug in exf_bulkformulae.F ?

[Patrick Heimbach]

Hi Eli,

you are right, there's a bracket missing, 
which makes the the -2*ATAN(x) + pi/2 term 
be added to both stable and unstable case.
I'll check in corrected code in a minute.
I'll try to assess later this week how computed 
fluxes differ for some NCEP atmospheric data sets.

Thanks for checking and pointing this out!

-Patrick



On Sunday 26 June 2005 06:45, eliyahu biton wrote:
  > Hello everyone!
  > I tried to follow the calculation of the turbulent heat fluxes, as they
  > appear within the subroutine 'exf_bulkformulae.F' at the 'exf' pkg and I
  > think that there is a problem with the calculation of the term 'psimh'
  > (line 394).
  >             psimh  = -psim_fac*huol*stable +
  >     &                     (exf_one - stable)*
  >     &                     log((exf_one + x*(exf_two + x))*
  >     &                     (exf_one + xsq)/8.) - exf_two*atan(x) +
  >     &                     pi*exf_half
  > According to Large & Pond paper from 1981 (eq 7) it should be (the last
  > two arguments should be included within the unstable case) ;
  >             psimh  = -psim_fac*huol*stable +
  >     &                     (exf_one - stable)*
  >     &                     (log((exf_one + x*(exf_two + x))*
  >     &                     (exf_one + xsq)/8.) - exf_two*atan(x) +
  >     &                     pi*exf_half)
  > I checked how this term calculated at subroutine bulkf_formula_lanl.F
  > (line  159 ) in 'bulk_force' pkg,  and there it  looks o.k. ( the last
  > two argument are included within the unstable case).
  >              psimh = -5. _d 0*huol*stable + (1. _d 0-stable)*
  >     &                    (2. _d 0*log(5. _d -1*(1. _d 0+x)) +
  >     &                     2. _d 0*log(5. _d -1*(1. _d 0+xsq)) -
  >     &                     2. _d 0*atan(x) + pi*.5 _d 0)
  >
  >
  > Eli

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Patrick Heimbach     Massachusetts Institute of Technology
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