AMTD Atmospheric Measurement Techniques Discussions AMTD Atmos. Meas. Tech. Discuss. 1867-8610 Göttingen, Germany 10.5194/amtd-3-1843-2010 On differentiating ground clutter and insect echoes from Doppler weather radars using archived data Rennie S. J. 1 Illingworth A. J. 1 Dance S. L. 1 2 Department of Meteorlogy, University of Reading, Reading, UK Department of Mathematics, University of Reading, Reading, UK 16 04 2010 3 2 1843 1860 Copyright: © 2010 S. J. Rennie et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://amt.copernicus.org/preprints/3/1843/2010/amtd-3-1843-2010.html The full text article is available as a PDF file from https://amt.copernicus.org/preprints/3/1843/2010/amtd-3-1843-2010.pdf

Normally wind measurements from Doppler radars rely on the presence of rain. During fine weather, insects become a potential radar target for wind measurement. However, it is difficult to separate ground clutter and insect echoes when spectral or polarimetric methods are not available. Archived reflectivity and velocity data from repeated scans provide alternative methods. The probability of detection (POD) method, which maps areas with a persistent signal as ground clutter, is ineffective when most scans also contain persistent insect echoes. We developed a clutter detection method which maps the standard deviation of velocity (SDV) over a large number of scans, and can differentiate insects and ground clutter close to the radar. Beyond the range of persistent insect echoes, the POD method more thoroughly removes ground clutter. A new, pseudo-probability clutter map was created by combining the POD and SDV maps. The new map optimised ground clutter detection without removing insect echoes.

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