Composition Changes Caused by the 2003 Solar Storm: MIPAS Measurements and Model Simulations

Manuel Lopez-Puertas⁽¹⁾, Bernd Funke⁽¹⁾ , S. Gil-Lopez⁽¹⁾ , Thomas von Clarmann⁽²⁾ , Herbert Fischer⁽²⁾ , N. Glatthor⁽²⁾ , Udo Grabowski⁽²⁾ , M. Höpfner⁽²⁾ , S. Kellmann⁽²⁾ , M. Kiefer⁽²⁾ , A. Linden⁽²⁾ , M. Milz⁽²⁾ , T. Reddmann⁽²⁾ , T. Steck⁽²⁾ , G. Stiller⁽²⁾ , and Miriam Sinnhuber⁽³⁾

⁽¹⁾ Instituto de Astrofisica de Andalucia, CSIC, Apdo. 3004, 18008 Granada, Spain
⁽²⁾ Forschungszentrum Karlsruhe, Postfach 3640, D-76021 Karlsruhe, Germany
⁽³⁾ Universität Bremen, FB 1, Otto-Hahn-Allee 1, 28359 Bremen, Germany

Abstract

Here we report the short-term (days) temporal evolution of the significant increase in NOx and decrease in O3. As a consequence of the NOx changes, alterations in other NOy species are also observed, e.g., in HNO3, N2O5, and ClONO2. The HOx composition is also perturbed by the solar proton events and evidence of its instantaneous change is observed in HOCl. These atmospheric composition changes have been studied by 1D and 2D models. While some changes are well understood (NOx, O3), others are not (HNO3, N2O5, ClONO2) and might require the revision of the chemical processes involved.

Favored by the dark condition and the downwards transport in the 2003-2004 NH polar winter, mid-term (months) composition changes have been observed down to the stratosphere. Significant enhancements in NOx and associated O3 depletion have been seen until March 2004. To quantify the O3 loss due to the solar storm, model runs with the 3D KASIMA model have been performed where NOx enhancements in the lower mesosphere have been taken from MIPAS observations. The results show a significant O3 depletion in the mid-upper polar stratosphere in this winter and subsequent spring.