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| Titel |
Gravity waves in simultaneous wind and temperature measurements in the strato- and mesosphere with a twin Doppler lidar |
| VerfasserIn |
Jens Hildebrand, Gerd Baumgarten, Jens Fiedler, Franz-Josef Lübken |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250087659
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| Publikation (Nr.) |
 EGU/EGU2014-1717.pdf |
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| Zusammenfassung |
| Wind and temperature measurements are fundamental to understand atmospheric dynamics.
However, a wide altitude range of the middle atmosphere from about 15 to 70 km is hard to
access by remote sensing instruments: the absence of free electrons prevents radar
measurements, and the optical depth prevents satellite remote sensing over the whole
altitude range. In-situ measurements by rockets allow only sporadic snapshots, while
balloons are not able to ascent high enough. Our Rayleigh/Mie/Raman lidar at the
Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR) in Northern
Norway (69° N, 16° E) allows to measure temperatures, aerosols, and wind speed
simultaneously. By applying two independently steerable telescopes we are able to measure
altitude profiles of two wind components at once. The wind retrieval currently allows
wind measurements in aerosol free parts of the middle atmosphere up to 80 km
altitude without external calibration. The temporal and spatial resolution is 1 h and
3 km, respectively. We present case studies which include data recorded during
stratospheric warmings and during periods of enhanced wave activity. Wave signatures are
clearly visible in time-height sections of temperature and horizontal wind and can be
combined to deduce parameters of the wave, like propagation and energy density. We
present also mean temperatures and winds from lidar measurements performed during
the winter seasons 2009–2012 and discuss their importance for wave propagation. |
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