Baroclinic instability demonstration

General scientific issues regarding ROMS

Moderators: arango, robertson

Post Reply
Message
Author
jklinck
Posts: 31
Joined: Mon Jun 30, 2003 2:29 pm
Location: CCPO/ODU, USA

Baroclinic instability demonstration

#1 Post by jklinck » Thu Mar 28, 2019 1:22 pm

I am using ROMS as part of a GFD class as a way to demonstrate some processes that are hard to show with analytical math.

My latest failure is to illustrate baroclinic instability using a periodic zonal channel with linearly stratified (both y and z) initial conditions (matching the setup in G Vallis's book). The f-plane channel is 2000x2000 km, dx=10km, Rd is 50km.

I am using biharmonic dissipation with very low coefficients (likely too low). Temperature and a linear EOS provide stratification. Some variability occurs but after 300 or so days, variability goes away. My latest effort is to put T nudging zones on the north and south to maintain the stratification, but this did not keep the instability running. The stratification did not diminish much by this time in any case.

Clearly, I am doing something dumb. Has anyone set up a baroclinic instability demonstration with ROMS? Are you willing to share your setup?

Thanks in advance.

John

Post Reply