Modeling of the Joule heating influence on the circulation and ozone concentration in the middle atmosphere

Abstract

A chemistry climate model is used to evaluate of the possible influence of Joule heating induced by the solar wind and interplanetary magnetic field (IMF) elements on the ozone concentration and dynamics of the Earth atmosphere. The Joule heating rates in the stratosphere are parameterized on the base of the time series of the solar wind and IMF parameters taken from the NASA database (Interplanetary Medium Data Book, NASA, USA, 1999) for 1996. The results of the 10-year-long model run with the additional Joule source of heat are compared with the output of the unperturbed (control) 20-year-long model run. Both simulations are performed in equilibrium mode with prescribed boundary conditions and for the minimum of the 11-year solar cycle. The comparison of the model outputs shows that the simulated atmosphere is rather sensitive to the introduced Joule heating. The most significant changes were found in the lower stratosphere of the northern hemisphere (NH). The NH lower-stratospheric temperature increases by 1–3 K almost throughout the whole year with the significance level at 95% or higher. In boreal summer, the changes of the ozone concentration are anti-correlated with the temperature as expected from the gas phase photochemical theory. In boreal autumn and spring, the variations of the ozone mixing ratio can be affected not only by the local temperature changes but also by the redistribution of the meridional circulation in the stratosphere. In the southern hemisphere (SH), the additional Joule heating leads to a significant increase of the stratospheric temperature for the austral winter ( ∼ 2 K ) . The most substantial SH ozone changes ( ∼ 10 % ) are found in the lower stratosphere during the austral spring.