10 November 2011
Almost all of the NOAA Doppler radars are being upgraded to a new technology called dual polarization. Simply put, the upgraded radars can send electromagnetic radio waves that are polarized both horizontally and vertically. Comparing the difference in the reflected energy allows forecasters to see much more than with conventional Doppler radar.
One BIG benefit is the ability top determine the shape of objects in the beam. Is it hail, or raindrops? Is it bugs or gruapel (slushy ice), or snowflakes? The radar at Vance, AFB in Enid, OK. has already been upgraded, and something very cool was noted after the earthquake last Saturday.
Look at the image below, and specifically at the top left panel that shows the hydrometer identification. The radar is seeing a small amount of flying insects, and this is very typical. Migrating swarms of birds are seen often on weather radar.
Now look at the image below, and again at the upper left (hydrometeor ID) panel. This image is just after the quake, and the shaking has caused birds and insects to take flight across the state!
Big kudos to the NWS Norman for putting this up on their Facebook page. Not only is it interesting but it shows students just how fascinating real world science can be. You can also see the quake effects on the NWS Norman Doppler radar. Notice the increase in ground clutter between the two scans below.
Is that cool or what!