Hi Marc, I had heard about this from Rob Matson a few weeks ago. However, once the upgrades are finished maybe we can start again where we left off.
Just know that we all appreciate what you guys do for us all. On Sun, Aug 31, 2014 at 9:30 AM, Marc Fries via Meteorite-list <[email protected]> wrote: > Howdy, all > > It has been a while since I've posted to the list, and unfortunately > I have to do so with bad news. You may have noticed that it has been a while > since we've found a new meteorite fall in weather radar imagery. We recently > found out why. It turns out that the NEXRAD radar system lost sensitivity in > the last major "upgrade". The radars were upgraded to allow two polarization > modes instead of one, which improves meteorologists' ability to discern > different types of precipitation. That upgrade came with a ~3 dBz sensitivity > loss. I've gone back to West, TX and found that 3 dBz of sensitivity loss > results in the loss of about 90% of all the meteorite reflectivity signal for > that fall. And it turns out the upgrade was in progress to the point that one > of the nearby radars was upgraded to dual-polarization in time for the > Sutter's Mill fall. The upgraded radar produced considerably less radar > reflectivity from the Sutter's Mill fall than another, single-polarization > radar th at was about the same distance away. To put it simply, we've lost a lot of our capability to find meteorite falls using the NEXRAD system. > It is not all gloom, however. The next round of NEXRAD upgrades will > install a modern, more sensitive detector to replace the 1980's-vintage > detectors currently on the NEXRAD sets. Pending availability of funding, that > will commence in 2016 and should get us back to where we were before the > upgrade. Also, now that we know what to look for, I'll start going back to > recent probable fall events and look for fall signatures. The Columbus OH, > northern Arkansas, and Dec 2013 event outside Tucson are worthy of > re-examination. I'm also looking into alternative sources of radar data. > So at least our extended dry spell has been explained. NOAA couldn't > care less about meteorite falls and so they don't communicate this sort of > information widely, and we're freeloading on their data and don't have a > voice in whether these "upgrades" are truly useful. If I had my druthers, I > would have asked them to upgrade the detectors first and then install the > dual-polarization capability. In my more official capacities I will try to > arrange a voice for the meteoritics community in radar dealings, but that may > take a while. > > Cheers, > Marc Fries > > ______________________________________________ > > Visit the Archives at http://www.meteorite-list-archives.com > Meteorite-list mailing list > [email protected] > https://pairlist3.pair.net/mailman/listinfo/meteorite-list -- Rock On! Ruben Garcia http://www.MrMeteorite.com ______________________________________________ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list [email protected] https://pairlist3.pair.net/mailman/listinfo/meteorite-list
