Simultaneous and co-located wind measurements in the middle atmosphere by lidar and rocket-borne techniques
We present the first comparison of a new lidar technique to measure winds in the middle atmosphere, called DoRIS (Doppler Rayleigh Iodine Spectrometer), with a rocket-borne in situ method, which relies on measuring the horizontal drift of a target (“starute”) by a tracking radar. The launches took p...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2016-08-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/9/3911/2016/amt-9-3911-2016.pdf |
| Summary: | We present the first comparison of a new lidar technique to measure winds in
the middle atmosphere, called DoRIS (Doppler Rayleigh Iodine Spectrometer),
with a rocket-borne in situ method, which relies on measuring the horizontal
drift of a target (“starute”) by a tracking radar. The launches took place
from the Andøya Space Center (ASC), very close to the ALOMAR observatory
(Arctic Lidar Observatory for Middle Atmosphere Research) at 69° N.
DoRIS is part of a steerable twin lidar system installed at ALOMAR. The
observations were made simultaneously and with a horizontal distance between
the two lidar beams and the starute trajectories of typically 0–40 km only.
DoRIS measured winds from 14 March 2015, 17:00 UTC, to 15 March 2015,
11:30 UTC. A total of eight starute flights were launched successfully from 14
March, 19:00 UTC, to 15 March, 00:19 UTC. In general there is excellent
agreement between DoRIS and the in situ measurements, considering the combined
range of uncertainties. This concerns not only the general height structures
of zonal and meridional winds and their temporal developments, but also some
wavy structures. Considering the comparison between all starute flights and
all DoRIS observations in a time period of ±20 min around each
individual starute flight, we arrive at mean differences of typically
±5–10 m s<sup>−1</sup> for both wind components. Part of the remaining
differences are most likely due to the detection of different wave fronts of
gravity waves. There is no systematic difference between DoRIS and the in situ
observations above 30 km. Below ∼ 30 km, winds from DoRIS are
systematically too large by up to 10–20 m s<sup>−1</sup>, which can be explained
by the presence of aerosols. This is proven by deriving the backscatter
ratios at two different wavelengths. These ratios are larger than unity,
which is an indication of the presence of aerosols. |
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| ISSN: | 1867-1381 1867-8548 |