Effect of Temperature Feedback and Hydrostatic Adjustment in a Stratospheric Model

Abstract

Calculated perturbations to stratospheric ozone are generally thought to be reduced when temperature feedback is included in the model. We find that when self-consistent hydrostatic adjustment is included with temperature feedback, there can be significant differences in the computed change in local ozone concentration. We present results in two frames of reference (changes in ozone at constant altitude and changes at constant pressure) to illustrate the importance of the frame of reference. Including hydrostatic adjustment is particularly important for calculations of the change in local ozone at constant altitude due to CFM, CO2 and H2O perturbations because large changes in the temperature structure are predicted. Only small differences are computed for increases in N2O. Air density adjustment in a constant pressure frame of reference is important when local temperature changes are large.