TWP-ICE case

TWP-ICE case carson Fri, 12/20/2019 - 15:31

TWP-ICE maritime deep convection case

Let’s move on to the TWP-ICE maritime deep convection case. Run the following to generate plots for this case:

cd ../../..

./gmtb_scm_analysis.py twpice_short_course.ini

cd plots_twpice_short_course/comp/active/

eog profiles_bias_T.png

While this case spans periods of clear skies, shallow convection, and deep convection, the plots represent time means over the actively deep convection period of the simulation. Let’s focus on the mean temperature profile, its bias (difference from observations), and the temperature tendencies due to forcing and physics processes.

profiles_mean_T.png
profiles_bias_T.png
profiles_mean_multi_T_forcing.png

Supplemental slide 21 provides some context for how the simulation changes through time and slides 22-24 show the plots mentioned above.

The mean temperature profile by itself doesn’t provide much information since the differences among the suites is much smaller than the magnitude of the quantity being plotted, but the profiles begin to hint at differences. The bias profile is more instructive in this case. One suite clearly has a cool bias throughout most of the atmosphere, while the remaining two suites have a similar magnitude cool bias, but are closer to zero bias at different heights in the column.

Q: Using the temperature tendencies plot, summarize the main contributors to the temperature biases.

eog profiles_mean_multi_T_forcing.png

A: The main contributor to the bias for the csawmg suite is reduced heating from the deep convection scheme (is this related to the scale-awareness of the Chikira-Sugiyama Arakawa-Wu scheme?). Aloft, the increased bias in the GFS suite appears to be from the microphysics scheme, although the longwave radiation scheme contributes too. The GSD suite has the least overall bias, although it has a much different relationship between the deep convection and microphysics that leads to a bit larger bias between 900 and 500 hPa.