Modelling the effects of ozone changes on climate

• Main Authors: Straume, A., Fortuin, J., Siegmund, P., Kelder, H., Roeckner, E.
• Format: Book Part
• Language: English
• Published: 2000
• Subjects: Antarctic; The Antarctic; Antarc*
• Online Access: http://hdl.handle.net/21.11116/0000-000E-0F96-9

Two 10-year climate-model simulations using different ozone climatologies are compared, where one climatology is from the nineteen-eighties and the other from the nineteen-sixties. The sensitivity of climate simulations due to the ozone distributions prior to and during the Antarctic ozone-hole period is in this way studied. Both model runs are compared to reanalysis data from the ECMWF. In the recent ozone climatology, less ozone is located around the tropopause during all seasons, and in the Antarctic lower stratosphere during spring. The model run using the recent ozone climatology differs from the other model run in the following ways: The tropopause region is slightly colder, whereas the lower and middle tropical stratosphere is warmer. In October, polar temperatures between 30 and 150 hPa are lower. The polar vortices are stronger, and more clouds form around the tropopause. When using the recent ozone climatology the model simulates the temperatures around the tropopause in the tropics better than the other model run compared to the reanalysis data, whereas the temperatures around and above the tropopause over the Poles are still too low.