Astronautics and aeronautics, 1967 - Chronology on science, technology, and policy

Chronology of astronautics and aeronautics in 196

Astronautics and Aeronautics, 1979-1984: A chronology

This volume of the Astronautics and Aeronautics series covers 1979 through 1984. The series provides a chronological presentation of all significant events and developments in space exploration and the administration of the space program during the period covered

Large scale dynamics of the atmosphere: Planetary waves

Planetary waves (PW) are global scale waves in the atmosphere, which are known to considerably impact weather patterns in the midlatitudes in the troposphere and the ozone distribution in the stratosphere. PW play an important role in coupling middle atmosphere dynamics. Due to the fact that climate change causes a decrease of the meridional temperature gradient, the strength of the zonal wind might decrease. This should, in turn, change the planetary wave activity (PWA). In order to quantify possible changes in the PWA we analyze ERA–Interim temperature data (10 m to 65 km height) on the Northern Hemisphere and calculate the so-called dynamical activity index (DAI) as measure for the PWA. We analyze the PWA to find indications for PWA changes and variability. We also use rotational temperature data from hydroxyl airglow measurements at UFS Schneefernerhaus (Germany) embedded in the international Network for the Detection of Mesospheric Change (NDMC) in the upper mesosphere/lower thermosphere (UMLT). We find an indication for a significant increase of the PWA in the stratosphere. The change of the PWA with higher zonal wavenumbers turns out to be strongest. This finding is in agreement with the expectation that a weakening of the meridional temperature gradient leads to improved vertical propagation conditions for planetary waves. With the empirical mode decomposition (EMD) we are able to extract non-stationary signals of the PWA time series. We further find that longer-term oscillations (QBO, ENSO and solar cycles) have a noticeable impact on the PW variability in all considered heights. Next to the 11-year cycle that is related to the sunspot-cycle in many studies, we also find a pronounced quasi-22-year signal. We tentatively interpret this signal as being due to the solar-magnetic-field (“Hale cycle”)

Science at the environmental research station Schneefernerhaus / Zugspitze

Das Buch enthält 22 Aufsätze, in denen die in der Forschungsstation Schneefernerhaus / Zugspitze aktiven Forscherinnen und Forscher ihre Arbeitsgebiete und bisherige Ergebnisse vorstellen. Die Aufsätze sind dabei so konzipiert, dass das Buch auch für die universitäre Lehre eingesetzt werden kann