|
Titel |
Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar |
VerfasserIn |
M. D. Shupe, I. M. Brooks, G. Canut |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1867-1381
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Measurement Techniques ; 5, no. 6 ; Nr. 5, no. 6 (2012-06-18), S.1375-1385 |
Datensatznummer |
250002971
|
Publikation (Nr.) |
copernicus.org/amt-5-1375-2012.pdf |
|
|
|
Zusammenfassung |
Turbulent dissipation rate retrievals from cloud radar Doppler velocity
measurements are evaluated using independent, in situ observations in Arctic
stratocumulus clouds. In situ validation data sets of dissipation rate are
derived using sonic anemometer measurements from a tethered balloon and high
frequency pressure variation observations from a research aircraft, both
flown in proximity to stationary, ground-based radars. Modest biases are
found among the data sets in particularly low- or high-turbulence regimes,
but in general the radar-retrieved values correspond well with the in situ
measurements. Root mean square differences are typically a factor of 4–6
relative to any given magnitude of dissipation rate. These differences are
no larger than those found when comparing dissipation rates computed from
tethered-balloon and meteorological tower-mounted sonic anemometer
measurements made at spatial distances of a few hundred meters. Temporal lag
analyses suggest that approximately half of the observed differences are due
to spatial sampling considerations, such that the anticipated radar-based
retrieval uncertainty is on the order of a factor of 2–3. Moreover, radar
retrievals are clearly able to capture the vertical dissipation rate
structure observed by the in situ sensors, while offering substantially more
information on the time variability of turbulence profiles. Together these
evaluations indicate that radar-based retrievals can, at a minimum, be used
to determine the vertical structure of turbulence in Arctic stratocumulus
clouds. |
|
|
Teil von |
|
|
|
|
|
|