All:
      The sensitivity of the radar in the 'Precipitation Mode' will
measure down to ~0 dBZ, which is enough to observe most bird migrations,
and many insect flights. Of course, the "Clear Air' mode
is much more sensitive and can observe backscattered radiation down to
~-28 dBZ at close ranges.
     There have been many papers written by Cornell and Clemson
Universities.  Impacts on Aviation were covered in a conference hosted
by Tim O'Bannon of the NWS Radar Operations Center (unfortunately
deceased)--see www.afonet.org/english.radar/radar.htm.
      Work is underway at the National Severe Storms Laboratory (and
other places) using dual polarimetric radars to identify birds, insects,
and other non-meterological data to-YES- remove these data so wind data
will represent the atmosphere!    (Improvements are being made to the
WSR-88D system now to allow dual polarimetry to be added in the late 2000s.)
     Bob Elvander (NWS radar meterologist-retired)
Joe McDaniel wrote:

>You have to make sure you are looking at the non-precipitation mode data. I think it is called something like "clear mode". The "precipitation mode" is tuned to look for rain/hail/etc. while the "clear mode" will see things like birds, cicadas, insects, and dust.  A few years ago Cornell did a study using the weather radar to track migration. It was interesting but whether anything ever came from it????
>
>Best,
>
>Joe
>
>
>

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