[mpas-developers] Test Case 6 Error

[Doug Jacobsen]

Hello All,

I have been working on the variable resolution results for TC2, TC5, and TC6
with Todd. We ran into an issue with the TC6 results, and after digging
through the code I found an error in the initialization for TC6. On lines
510 and 511 of module_test_cases.F the function AA(theta) is defined as

AA = 0.5 * w * (2.0 * omega + w) * cos(theta)**2.0 + &
      0.25 * K**2.0 * cos(theta)**(2.0*R) * ((R+1.0)*cos(theta)**2.0 +
2.0*R**2.0 - R - 2.0 - 2.0*(R*cos(theta))**2.0)

In the Williamson paper, he defines this as:

AA = 0.5 * w * (2.0 * omega + w) * cos(theta)**2.0 + &
      0.25 * K**2.0 * cos(theta)**(2.0*R) * ((R+1.0)*cos(theta)**2.0 +
2.0*R**2.0 - R - 2.0 - 2.0*R**2*cos(theta))**-2.0

The main (or only) difference that I found was in the currently implemented
case, cos(theta) (the last term) is squared, but it really need to be raised
to the -2 power.

Doug
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/mpas-developers/attachments/20100318/edf288e1/attachment.html