Continuation of the previous long-term stay of John Hampson (CNRC, Paris) has been organized to strengthen the collaboration after the completion of the 5FP Project SOLICE. The improvement of performance of the middle atmosphere model MSDOL was tested in polar regions. This visit brought the center another aspect of climate change related with processes in middle atmosphere, where the sensitivity of chemistry to atmospheric cooling in connection with GHG increase is significant. A seminar on the stratosphere and middle atmosphere modeling took place on November 1, 2005.