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In this article, five velocity-based energy dissipation rate (EDR) retrieval techniques are assessed. The EDR retrieval techniques are applied to Doppler measurements from Transportable Atmospheric Radar (TARA)—a precipitation profiling radar—operating in the vertically fixed-pointing mode. A generalized formula for the Kolmogorov constant is derived, which gives potential for the application of the EDR retrieval techniques to any radar line of sight (LOS). Two case studies are discussed that contain rain events of about 2 and 18 h, respectively. The EDR values retrieved from the radar are compared to in situ EDR values from collocated sonic anemometers. For the two case studies, a correlation coefficient of 0.79 was found for the wind speed variance (WSV) EDR retrieval technique, which uses 3D wind vectors as input and has a total sampling time of 10 min. From this comparison it is concluded that the radar is able to measure EDR with a reasonable accuracy. Almost no correlation was found for the vertical wind velocity variance (VWVV) EDR retrieval technique, as it was not possible to sufficiently separate the turbulence dynamics contribution to the radar Doppler mean velocities from the velocity contribution of falling raindrops. An important cause of the discrepancies between radar and in situ EDR values is thus due to insufficient accurate estimation of vertical air velocities. [ABSTRACT FROM AUTHOR]

Combining Doppler and polarimetric information is advantageous for atmospheric studies. On the one hand, Doppler information gives insight into the microphysical and dynamic properties of radar targets, that is, radial velocity and its variability. The polarization diversity, on the other hand, has a strong link to the microphysical properties of targets such as shape and orientation. Polarimetric measurements, however, have an adverse effect on Doppler processing. Measurements of the complete scattering matrix require at least two pulses and result in the reduction of the maximum unambiguous Doppler velocity that can lead to Doppler spectrum aliasing. Moreover, dynamic properties of targets, because of the nonsimultaneity of the measurements performed with different polarizations, affect the accuracy of polarimetric radar measurements. A solution to these two problems is given in this paper. It is shown that by applying a relatively simple processing technique the effect of nonsimultaneous polarimetric measurements can be reduced even in the case of strong Doppler spectrum aliasing. This leads to better estimates of the copolar cross-correlation coefficient. Furthermore, this processing results in the maximum unambiguous Doppler velocity as if no polarimetric measurements were performed, with the added advantage of obtaining the actual Doppler velocities. To illustrate the proposed processing technique, precipitation measurements taken with the Delft Atmospheric Research Radar (DARR) are used. [ABSTRACT FROM AUTHOR]