Ozone heating and the destabilization of traveling waves during summer

Abstract

The effects of ozone heating on the linear stability of lower stratospheric traveling waves of the summertime, extratropical circulation are examined. Based on coupled equations for the quasigeostrophic potential vorticity and ozone volume mixing ratio, it is shown that the diabatic heating arising from ozone advection can offset the damping due to Newtonian cooling, leading to wave amplification and significant changes in the structure and zonally rectified fluxes of the wave fields in both the lower stratosphere and troposphere. The vertical profile of the zonal mean wind plays a crucial role in determining whether the ozone heating destabilizes eastward and/or westward traveling disturbances.

On the Approximation of Local and Linear Radiative Damping in the Middle Atmosphere

“…Significant positive correlations between temperature and shortwave heating rate are found throughout the summer lower stratosphere, with negative effective damping rates peaking at 20.04 day 21 above the summer pole. This is consistent with the unstable, linear, westward-traveling Rossby modes found there by Nathan et al (1994). The increased damping toward the polar region is in part a result of the length of the polar day.…”

“…Where ozone is under dynamical control, on the other hand, eddy transport tends to lead to positive correlations between ozone and temperature (Hartmann 1981). As a result, in the lower summer stratosphere, shortwave heating can destabilize certain linear modes (Nathan et al 1994). Ozone perturbations also have a significant, nonlocal ''opacity'' effect as they allow more or less shortwave radiation to penetrate to lower levels.…”

“…Where ozone is under photochemical control, there is a strong negative linear correlation between temperature and shortwave heating. Where it is controlled by transport, background ozone gradients tend to lead to a positive correlation between temperature and shortwave heating (Hartmann 1981;Nathan et al 1994). In the latter case, the regression coefficient between temperature and shortwave heating is weaker.…”

Zonal asymmetries in middle atmospheric ozone and water vapour derived from Odin satellite data 2001–2010

“…During summer (JJA: June, July, August) there are only minor planetary wave patterns in the lower stratosphere which might be due to zonal asymmetries in eddy mixing processes in the upper troposphere/lower stratosphere (UTLS) region induced by synoptic-scale baroclinic waves. In relation to previous works (e.g., Garcia and Hartmann, 1980;Stolarski and Douglass, 1985;Nathan et al, 1994;Rood and Douglass, 1985;Douglass et al, 1985;Froidevaux et al, 1989;Peters and Entzian, 1999) both the double-peak structure of O * 3 in the vertical occurring during winter, with pronounced amplitude in the lower and the upper stratosphere, and the fact that the wave one pattern of O * 3 does not show a westward shift in phase with increasing height (as shown by Fig. 1.1b), as usually found in other quantities like temperature or geopotential height, can be interpreted as a combination of transport processes in the lower and middle stratosphere (where the chemical lifetime of ozone is long and ozone and temperature are correlated), and temperaturedependent chemistry in the upper stratosphere (where the lifetime of ozone is short and ozone and temperature are anticorrelated).…”

“…In the lower and middle stratosphere O 3 is controlled mainly dynamically by transport processes where its chemical lifetime is relatively long, but controlled mainly photochemically in the upper stratosphere and mesosphere where its chemical lifetime is relatively short (e.g., Garcia and Hartmann, 1980;Stolarski and Douglass, 1985;Nathan et al, 1994). Therefore, both transport processes and temperaturedependent chemistry play an important role in determining the stationary wave patterns in O 3 .…”