Project Paper assistance.

[Patrick Harris]

I'm working on a position paper on tornadoes and one of the requirement is: "any new discoveries scientists have made in relation to tornadoes".

Don't need you to do my report, just give a a couple of latest and greatest theories or scientific discoveries to go research on my own. A theory or discovery that I may not have found on mine own. I like to include the unique and different in my papers.



Thanks
Patrick

 

[Patrick Marsh]

Take a look at what Paul Markowski is researching. Particularly his theory of "vortex arches".

 

[Dave Kaplow]

You might want to look at some of the results that are just now starting to be published from the Vortex 2 experiment, in particular I'm thinking about the radar "low reflectivity ribbon" seen on some of the tornadic supercells they targeted. It's a fascinating finding, absolutely brand new, and no one knows what, if anything, it may mean.

 

[Jeff Snyder]

You might want to look at some of the results that are just now starting to be published from the Vortex 2 experiment, in particular I'm thinking about the radar "low reflectivity ribbon" seen on some of the tornadic supercells they targeted. It's a fascinating finding, absolutely brand new, and no one knows what, if anything, it may mean.

I (with Bluestein, Venkatesh, and Frasier as coauthors) have a paper coming out in Monthly Weather Review (should be available as an Early Online Release manuscript shortly) that details some of the low reflectivity ribbon observations our group collected with the polarimetric UMass XPol mobile radar between 2008 and 2010. We also have a couple of examples from spring 2011 using RaXPol that weren't included in that paper. Though most of our examples of the LRR were made in tornadic supercells, I'm very hesitant to state that the signature has any significant meaning at this time. We try to focus most of our efforts on tornadic supercells, so we dont' really have a good cross-section of all supercells to know whether the observation that most of our LRRs have occurred with tornadic supercell is coincidence or has real meaning. Given that the LRR represents a significant heteorogeneity in the reflectivity and, usually, differential reflectivity fields (implying a significant heteorogeneity in the drop size distribution), it seems probable to me that there is also an appreciable buoyancy gradient (or heteorogeneity in the thermo field) where the LRR is located. Beyond that, we just don't know yet. We do have one really interesting case (22 May 2008 in NW OK) in which there are a series of closely-spaced vortices along the LRR (the radar was <5 km from the hook echo at that time, so we had the spatial resolution to see these vortices) immediately preceeding tornadogenesis. Again, though, the sample size is very limited.

I agree with Patrick -- check out some of the work that Markowski is spearheading regarding vortex arches. Karen Kosiba of CSWR is also looking into an observed LRR associated with the Goshen Co tornadic supercell on 6/5/09 from a dual-Doppler perspective, but I haven't seen an extended abstract or formal paper for this work yet.

I'll post a link to the article when it gets posted on the AMS website.

 

[Jeff Snyder]

One more point -- I recommend reading the not-yet-in-print overview article about VORTEX 2 that will appear in the Bulletin of the American Meteorological Society (BAMS) soon. It is available as an Early Online Release, since it's not formatted quite as nicely as it'll be when it appears in BAMS; you'll need to flip back and forth if you want to see the figures when you read through the text, or you can just wait until it appears in BAMS (next issue? no idea). In the mean time, the EOR version can be accessed at:

Wurman, Dowell, Richardson, Markowski, Rasmussen, Burgess, Wicker, and Bluestein, 2012: The Second Verification of the Origins of Rotation in Tornadoes Experiment: VORTEX2. Bull. Amer. Meteor. Soc., in press.

 

[Patrick Harris]

Thanks for your help... A lot of good information to look at.