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.
The ALOMAR Rayleigh/Mie/Raman (RMR) lidar is an active remote sensing
instrument for the investigation of the Arctic middle atmosphere
during day and night. It is located in Northern Norway and
operated on a routine basis to measure relative density profiles
and aerosol properties in the stratosphere and mesosphere since
1995. Temperature profiles derived from the density measurements
assuming hydrostatic equilibrium are used to investigate the mean
temperature structure as well as gravity waves in the polar middle
atmosphere. During the last two years, temperature data were
acquired for approximately 2100 hours. A subset of this data basis
was used to determine the potential energy density to characterize
the gravity wave activity above the station. Noctilucent clouds
(NLC) are the highest clouds of the Earth's atmosphere and a
visible sign of extreme atmospheric conditions with temperatures
far below radiative equilibrium. During the last 7 years a
continuous data set with 1880 measurement hours was acquired
during the summer seasons, of which 640 hours contain NLC
signatures. This actually most extensive lidar acquired NLC
archive was analyzed regarding brightness, altitude, vertical
extent, as well as occurrence frequency of noctilucent clouds
above ALOMAR.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.