Academic Journals Database
Disseminating quality controlled scientific knowledge

Evaluation of turbulent dissipation rate retrievals from Doppler cloud radar

ADD TO MY LIST
 
Author(s): M. D. Shupe | I. M. Brooks | G. Canut

Journal: Atmospheric Measurement Techniques Discussions
ISSN 1867-8610

Volume: 5;
Issue: 1;
Start page: 747;
Date: 2012;
VIEW PDF   PDF DOWNLOAD PDF   Download PDF Original page

ABSTRACT
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 15-m tower sonic measurements made at spatial distances of a few hundred meters. Moreover, radar retrievals are 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.
Save time & money - Smart Internet Solutions     

Tango Jona
Tangokurs Rapperswil-Jona