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    Seasonal variation of nocturnal temperatures between 1 and 105 km altitude at 54° N observed by lidar
    (München : European Geopyhsical Union, 2008) Gerding, M.; Höffner, J.; Lautenbach, J.; Rauthe, M.; Lübken, F.-J.
    Temperature soundings are performed by lidar at the mid-latitude station of Kühlungsborn (Germany, 54° N, 12° E). The profiles cover the complete range from the lower troposphere (~1 km) to the lower thermosphere (~105 km) by simultaneous and co-located operation of a Rayleigh-Mie-Raman lidar and a potassium resonance lidar. Observations have been done during 266 nights between June 2002 and July 2007, each of 3–15 h length. This large and unique data set provides comprehensive information on the altitudinal and seasonal variation of temperatures from the troposphere to the lower thermosphere. The remaining day-to-day-variability is strongly reduced by harmonic fits at constant altitude levels and a representative data set is achieved. This data set reveals a two-level mesopause structure with an altitude of about 86–87 km (~144 K) in summer and ~102 km (~170 K) during the rest of the year. The average stratopause altitude is ~48 km throughout the whole year, with temperatures varying between 258 and 276 K. From the fit parameters amplitudes and phases of annual, semi-annual, and quarter-annual variations are derived. The amplitude of the annual component is largest with amplitudes of up to 30 K in 85 km, while the quarter-annual variation is smallest and less than 3 K at all altitudes. The lidar data set is compared with ECMWF temperatures below about 70 km altitude and reference data from the NRLMSISE-00 model above. Apart from the temperature soundings the aerosol backscatter ratio is measured between 20 and 35 km. The seasonal variation of these values is presented here for the first time.
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    Thermal structure of the mesopause region during the WADIS-2 rocket campaign
    (Göttingen : Copernicus GmbH, 2019) Wörl, R.; Strelnikov, B.; Viehl, T.P.; Höffner, J.; Pautet, P.-D.; Taylor, M.J.; Zhao, Y.; Löbken, F.-J.
    This paper presents simultaneous temperature measurements by three independent instruments during the WADIS-2 rocket campaign in northern Norway (69° N, 14° E) on 5 March 2015. Vertical profiles were measured in situ with the CONE instrument. Continuous mobile IAP Fe lidar (Fe lidar) measurements during a period of 24 h, as well as horizontally resolved temperature maps by the Utah State University (USU) Advanced Mesospheric Temperature Mapper (AMTM) in the mesopause region, are analysed. Vertical and horizontal temperature profiles by all three instruments are in good agreement. A harmonic analysis of the Fe lidar measurements shows the presence of waves with periods of 24, 12, 8, and 6 h. Strong waves with amplitudes of up to 10K at 8 and 6 h are found. The 24 and 12 h components play only a minor role during these observations. In contrast only a few short periodic gravity waves are found. Horizontally resolved temperatures measured with the AMTM in the hydroxyl (OH) layer are used to connect the vertical temperature profiles. In the field of view of 200km×160km only small deviations from the horizontal mean of the order of 5K are found. Therefore only weak gravity wave signatures occurred. This suggests horizontal structures of more than 200 km. A comparison of Fe lidar, rocket-borne measurements, and AMTM temperatures indicates an OH centroid altitude of about 85 km. © 2019 Copernicus GmbH. All rights reserved.