Abstract
Inertial instability is a hydrodynamic instability that occurs in strong
anticyclonic flow and is typically diagnosed by negative absolute
vorticity in the Northern Hemisphere. As such, inertial instability is
often observed on the anticyclonic-shear side of jet streams, yet the
release of the instability in this environment is still poorly
understood. We simulate the release of inertial instability near an
idealized midlatitude zonal jet compared to a control simulation with no
instability. We find that the release of the instability results in flat
meridional wind perturbations of up to 7 m s−1 over 200 km that persist
for several days, in addition to radiating inertia-gravity waves several
hundreds of kilometers away from the unstable region. Furthermore, these
perturbations instigate light–moderate occurrences of clear-air
turbulence around the unstable region that persist for up to 12 hours.