CAWSES Projekt - SACOSAT

Models of solar total and spectral irradiance variability of relevance for climate studies

Prof. Dr. Justus Notholt
Universität Bremen
Institut für Umweltphysik
Otto-Hahn Allee 1
28359 Bremen
notholt@uni-bremen.de

• Dr. Holger Bremer
  bremer@iup.physik.uni-bremen.de
• Dr. Miriam Sinnhuber
  miriam@iup.physik.uni-bremen.de
• Dr. Gerd Hochschild
  hochschild@imk.uka.de

The goal of this project is to measure changes in O₃ and H₂O in the stratosphere and mesosphere in the Arctic at Ny-Ålesund/Spitsbergen and the Tropics at Mérida/ Venezuela with special emphasis on the effects due to solar variability. These measurements will allow us to study the following scientific topics:

• Measure the influence of the diurnal and seasonal variability of water vapour on the ozone chemistry in the tropics compared to the high Arctic.
• Investigate the influence of UV variability compared to the influence of charged particles on ozone by comparisons of measurements at the two sites.
• Estimate the vertical transport of mesospheric air downward into the upper and middle stratosphere
• Assess the long-term impact of variations in water vapour concentrations on the stratospheric ozone chemistry in the Arctic and the Tropics.

SACOSAT