Lidars provide an important tool to measure temperature and minor constituents in the atmosphere up to ~110 km
altitude with high accuracy and temporal resolution. The Leibniz-Institute of Atmospheric Physics operates various
lidars for the whole range between troposphere and lower thermosphere. The lidars are installed at Kühlungsborn,
Germany (54°N, 12°E), at the ALOMAR site, Norway (69°N, 16°E), or in a mobile 20-foot container. Summertime
soundings in polar regions as well as coverage of tides and gravity waves require measurements during full daylight.
With a standard lidar the daylight background is several magnitudes larger than the signal in the mesosphere.
Narrowband spectral filtering by etalons as well as spatial filtering by small fields of view (~50 μrad) are realized
instead. At this low FOV turbulence and jitter of the beam pointing affects the signal and have to be compensated. We
describe the techniques applied at our lidars. Additionally we will discuss the influence of the etalon filter technique on
calculated temperature profiles. The etalon transmission of the Doppler-broadened backscatter signal is temperature
dependent and has to be taken into account to avoid systematic errors. Overall, narrow-band lidars provide temperature
profiles in the whole range up to the lower thermosphere. We will present observations of temperatures profiles of the
lower and middle atmosphere as well as noctilucent clouds (NLC). These quantities provide important insights into the
dynamics of the middle atmosphere. Time-resolved and averaged profiles of observations at the different locations will
be shown and the results from different latitudes compared.
At the mid-latitude location of Kuehlungsborn (54°N, 12°E) a resonance lidar and a Rayleigh-Mie-Raman (RMR) lidar are operated to observe e.g. the occurrence and particle properties of Noctilucent Clouds (NLC) and to measure continuous temperature profiles from the troposphere to the lower thermosphere. For the temperature profiles the two lidars (RMR lidar and potassium lidar) and three different measurement methods (rotational Raman, Rayleigh/vib. Raman, Doppler resonance) are combined. The profiles are obtained continuously between 1 and 105 km with a temporal and vertical resolution of at least 15 min and 1 km, respectively. Temperature fluctuations due to gravity waves and tides with amplitudes of up to ±20 K are observed. In summer during the cold phases of waves the temperature above 80 km drops occasionally below the frostpoint temperature. However, the mean temperature below 83 km is a few Kelvin above the frost point and only for about two weeks in summer the air becomes continuously supersaturated between 85 and 90 km. Therefore, the existence of NLC ice particles above our site is only allowed in the cold phases of waves. We will present lidar-observations of NLC and temperatures below and above the NLC layer showing the coupling of the NLC to supersaturated air in the mesopause region.