STRAWMAN PROPOSAL FOR

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STRAWMAN PROPOSAL FOR GLOBAL BAROCLINIC CORE
EVALUATION FOR CAM CANDIDATES
David Williamson National Center for Atmospheric
Research
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Assume that the basic numerical approximations
have demonstrated some desired characteristics
locally conservative consistent mass
and tracer conservation shape
preserving Assume satisfactory performance in
shallow water tests Need an indication of
computing resources required and an estimate of
what they might be after additional software
engineering i.e. optimal code is not needed
at this stage
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Unfortunately baroclinic core evaluation remains
somewhat subjective In some tests there are no
absolute criteria looking for strong points
looking for potential flaws
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BAROCLINIC CORE ALONE
Jablonowski - baroclinic instability test case
(NCAR/TN-469STR) http//library.ucar.edu/uhtbin/
cgisirsi/RUfall9E1L/0/131920033/523/8788 At
what resolution does the core produce the
reference solutions to within their
uncertainties Amplitude and phase errors at
lower resolutions Polvani et al - baroclinic
instability test case MWR, 2004, pp.
2539-2552 Absolute convergence but
requires and dominated by strong del2
diffusion Giraldo and Rosmond - Rossby-Haurwitz
wavenumber 4 MWR, 2004, pp.133-153
Based on Monaco and Williams, NPS TN, 1975
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BAROCLINIC CORE WITH IDEALIZED FOCING
Held-Suarez, BAMS, 1994, pp. 1825-1830
Overall behavior as with other cores
(climate modelers norm) Boar-Denis, CD, 1997,
pp. 359-374 Requires zonal averages
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BAROCLINIC CORE WITH CAM3.1 PARAMETERIZATIONS
AQUA-PLANET (at proposed application
resolutions) APE http//www.met.reading.ac.uk
/mike/APE/ape_home.html Neale and Hoskins,
ASL, 2000, pp.101-107 True solution is not
known Look for behaviors that are not
inconsistent with those of Eulerian,
semi-Lagrangian and Finite Volume cores,
and/or within the range of acceptable APE
participants