M14 Middle Atmosphere Science

IAMAS (Meteorology)

26-Jun-2015, 15:00 - 16:30

Abstract content:

A nudged-CCM simulation of chemical constituent distribution at Northern Hemisphere high latitudes observed by SMILES during the 2010 SSW

Stratospheric sudden warming (SSW) is a drastic phenomenon in the winter stratosphere. During SSW, distribution of chemical constituents, associated chemical forcing, and transport of chemical constituents change significantly inside and outside the polar vortex. In this study, chemical constituent distributions before and during a major SSW in January 2010 were simulated by the Model for Interdisciplinary Research on Climate 3.2-Chemistry-Climate Model (CCM) nudged toward the ERA-Interim reanalysis data, and the simulation results were compared with Superconducting Submillimeter-wave Limb-Emission Sounder (SMILES) observations. In addition, the dynamical and chemical budgets of ozone in the high-latitude lower stratosphere were analyzed. We discuss the ozone budget inside and outside the Arctic polar vortex. The analyses indicate that inside the polar vortex during the SSW, ozone concentration increased moderately as a result of partial cancelation between large negative ozone forcing due to chemical ozone destruction and large positive ozone forcing due to horizontal ozone influx from outside the vortex as well as downward advection. In a high ozone region outside the vortex, the large ozone increase is primarily due to a downward advection of ozone. These ozone budgets during SSW are compared with those in the transformed Eulerian mean framework. In the zonal-mean framework, ozone at high latitudes increases because of an enhanced downward advection, which corresponds to the large downward ozone advection outside the polar vortex. SMILES observations, nudged-CCM simulations, and the budget analyses reveal a highly longitudinal-dependent ozone budget at high latitudes during the SSW.

H. Akiyoshi1, T. Nakamura2, T. Miyasaka3, M. Shiotani4, M. Suzuki5.
1National Institute for Environmental Studies, Tsukuba, Japan.
2National Institute of Polar Research, GRENE Project, Tachikawa- Tokyo, Japan.
3Oracle Corporation Japan, Oracle Corporation Japan, Tokyo, Japan.
4Kyoto University, Research Institute for Sustainable Humanosphere, Uji- Kyoto, Japan.
5JAXA, ISAS, Sagamihara- Kanagawa, Japan.


SMILES     ozone     polar vortex     ERA-interim     nudged-CCM     SSW     the year 2010