zum ThemaMonitoring of the ozone layer obove Switzerland: Variability from diurnal to decadal scales
Zeit: Donnerstag, 10. April 2014, 12:00 Uhr (s.t.)
Ort: SR des Wegener Center im 1. Stock, Brandhofgasse 5
Moderation: Prof. Gottfried Kirchengast
Herzlich willkommen!
Ozone plays a crucial role for chemistry, radiative transfer, energetics and dynamics of the Earth's atmosphere. Within the Network for the Detection of Atmospheric Composition Change (NDACC), a groundbased ozone microwave radiometer continuously monitors stratospheric and mesospheric ozone above Bern since 1994. The temporal and vertical resolution of the measured ozone profiles are about 5 min and 10 km respectively. The groundbased ozone data are mainly used for intercomparison and control of satellite measurements. All-daytime coverage of groundbased ozone microwave radiometry permits the measurement of the daily ozone cycle. The daily ozone cycle causes biases in long-term trend estimates of global ozone derived from satellite measurements. Numerical simulations of the daily ozone cycle show how ozone photochemistry, atmospheric composition and transport processes modulate the daily ozone cycle on global and regional scale. It is evident that the expected, slow recovery of the stratospheric ozone layer only can be detected in combination with an accurate correction of the diurnal effects in satellite data. Finally, we discuss the strong effects of planetary waves and periodic displacements of the polar vortex on the ozone distribution above Bern.
