Mathematisch-Naturwissenschaftliche Fakultät

Institut für Atmosphärenphysik

Fachgebiet: Atmosphärenphysik

Betreuer: Prof. Dr. Franz-Josef Lübken



Dipl. Ing. (FH) Jens Lautenbach
(e-mail: Lautenbach@iap-kborn.de )

Experimentelle Untersuchungen mit einem Lidar zur thermischen Struktur der Mesopausen-Region bei polaren und mittleren Breiten

Remote sensing of layers in the upper mesosphere can provide important information about the thermal and dynamical background conditions in a part of our atmosphere which is experimentally difficult to access. This work presents a comprehensive study of the temperature structure of the Earth’s middle atmosphere. Temperature and potassium density profiles in mesopause altitudes (80–105 km) are measured using an groundbased potassium resonance lidar. The mean state of the atmospheric temperature is characterized at polar and mid latitudes.

During three campaigns (2001–2003) at the polar island Svalbard (78°N) a unique data set from February to October is obtained. The seasonal variations of potassium density and temperature are analyzed. In addition, observations at the Leibniz-Institute of Atmospheric Physics (54°N) were carried out (2002–2005). The analyses of these two data sets support the concept of a global two-level mesopause with low temperatures during summer time.

At Svalbard the temperatures are compared with co-located and simultaneously measured polar mesosphere summer echoes (PMSE). In particular the temperature structure at the topside and above of PMSE is analyzed. In contrast to the present PMSE theory it is shown that the temperature above of PMSE is low enough to allow the existence of PMSE.

Another object of this work was the further development of the lidar system. An iron doppler lidar system was developed to enhance functionality and daylight capability. By considering the isotopic shifts of the iron isotopes a solution for exact temperature retrieval is pointed out as well as the use of etalons for daylight suppression.