Much Ado about Naming Tropical Cyclones

While it’s still there, check out a Houston Chronicle article, within which former NHC director Neil Frank (for whom I do have a good deal of respect, BTW) questions NHC’s decision to name several weak or debatably tropical 2007 storms.

If Neil was quoted in good context in that article — never a given in the modern attack-media — he seems to advocate turning back the clock and treating some of this year’s hybrid or cold-to-warm core transitions as something other than tropical. If so, I don’t agree. His statements are patently oversimplified and unfair to the forecasters now there. We as scientists need to do the best we can, under the best understanding currently available, and call a spade a spade. This means tropical if it meets all the criteria (as did, for example, Erin over Oklahoma, which was: warm core, 35+ kt sustained for several hours, structurally characteristic with an eye, eyewall and spiral band, effectively devoid of baroclinicity and ingesting low level temperature and moisture fields similar to the tropics). [Erin’s final “best track” info still hasn’t been fully determined yet.]

1979-era rules of thumb don’t apply in the framework of today’s vastly better sensor sampling. This includes QuikSCAT, coastal and inland fixed mesonets, mobile observing systems and deployed sensors in landfalling storms, fixed and mobile Doppler radars, and other tools that were either unavailable or much more primitive in that era. We’re seeing named storms that wouldn’t have been named way back when, you bet. But there are valid reasons.

This isn’t because of some desire to inflate numbers for verification’s sake or to support any “global warming” hysteria, as some of the reactionary but grotesquely ignorant BLOGgers have posted in response to that article. I’ll respond for now to the BLOGs and postings in response to that article, not to Neil’s quotes…

It’s a lot harder to play verification games with TCs than with severe storms, given the intense scrutiny that every single Atlantic event gets in real time from storm aficionados of all flavors worldwide, as well as real meteorologists and meteorologist wanna-be’s. I firmly believe that NHC is not playing verification games, has not, and won’t be. I know those forecasters and they’ve got more integrity than that. By contrast, locally inflating a thunderstorm wind report to verify a warning, recording a dubious gust estimate that happens to occur in a warning, turning a “marble into a shooter” hailstone, or declaring an ongoing event as occurring one minute into the warning, is not so hard to do, and can go under the radar (pun intended) amidst the prevailing flurry of tens of thousands of other reports every year. Does that happen nowadays in verifying local storm warnings? I can’t firmly vouch or prove either way. But I am quite confident that NHC is acting with the utmost integrity in classifying tropical systems. So…

As for those claiming NHC is playing “global warming” games, that’s unadulterated crap. Real live NHC forecasters aren’t dealing with climate change in their forecasting and verification duties — just trying to make the best predictions possible and figure out what happened with each storm after the fact, using all available evidence. There is no grand conspiracy, period…no bogeyman under the bed, no chains rattling in the attic, no little green space-alien freaks planting chips in our heads, and no massive hidden agenda on naming tropical systems. Of course, irrational paranoids in the BLOGosphere never will be convinced otherwise!

Back to Neil’s implication that marginal or hybrid systems could be left alone: Now isn’t an era when some P.O.S., no-impact swirly in the middle of the subtropical Atlantic can be swept under the rug! NHC cannot just ignore marginal systems “way out there” or fail to name a storm that has strong evidence of qualifying characteristics.

Unlike in the 70s and 80s, satellite, radar, RECON and other data is available almost instantly, worldwide, to anyone with Internet connectivity. This audience runs the gamut from some really brilliant atmospheric scientists to beer-swilling, ill-educated conspiracy mongers drooling all over their keyboards in facile worship of Art Bell. From both extremes and everywhere between, accountability exists as never before, and the spotlight shines bright and hot. It’s also true that not every customer will agree with the results, given the sheer size and diversity of the user base behind those spotlights. Clearly Neil and some of the BLOGgers aren’t happy with it. So be it. Can’t please everyone…

In the tropical arena, we are getting more marginal or atypical systems named than before for at least these three reasons, the first also being a legitimate reason we’ve got more severe local storm reports in the U.S. now as well:

1. They are being sampled much more thoroughly, both remotely and in situ, and

2. Scientific understanding of their existence, behavior and morphology has improved, contributing to better documentation of the processes and transitions and distinctions between tropical and extratropical. As meteorologists continue to gain understanding, and as technological and measuring capabilities improve, classification of tropical systems will and should evolve too!

3. Both policies and practices on naming subtropical systems have loosened since the 80s, and even since I was there in the early 90s. We also know the atmosphere doesn’t give a flip about naming policy, and will keep cranking out these systems whether or not we decide to call them TS Bubba, STS Bubba or just “low.” Therefore, the climatological record will include biases related to either written or unwritten rules changes on nomenclature. For a tropical or climate researcher, this sucks; but it is what it is. Adapt and adjust accordingly. Severe storms scientists are having to account for a much larger, crazier and more change-prone database.

These also are good reasons not to compare apples to oranges and try to make sweeping climatic conclusions from our flawed and inconsistently gathered records of Atlantic (or even worldwide) TCs. The same holds true even more so in the severe weather arena, where even relatively advanced U.S. records haven’t been kept as long, and deep flaws in the data are well enunciated in the literature.

What is the good researcher to do? Any atmospheric scientist worth his/her degree(s) is absolutely obligated to either
1. Fully disclose and acknowledge the recording trends and biases in the cyclone data used for his/her work, or
2. Carefully and openly document, normalize and statistically detrend the data for all known biases, so as to minimize the impact on the storm climatology of the evolution in sampling, recording and naming of these storms.


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