Global Warming and Shear

[Frank2]

Since GW is back in the news again:

http://www.guardian.co.uk/environment/2 ... 010-record

it's also of interest to read the below, released 3 years ago:

http://www.sciencedaily.com/releases/20 ... 182843.htm

it does seem that in recent years shear is present even during non El Nino periods, or periods when shear-producing weather systems (fronts, troughs, ULL's, etc.) are not present...

Of course no one knows exactly what this means, though interesting to note...

[hurricaneCW]

Shear is and will always be present even in neutral and la nina conditions. Your never going to have a basin that's shear free for the season. We'd be having 20+ storms every year if that happened. I'm not sure how global warming will affect the tropical season, but it does seem likely that with the rise in water temperatures that the strength of storms will increase. So we trade 15+ storm seasons with 10 storm seasons but half of them are majors.

[Frank2]

The thinking is that there might be fewer storms, but those that do form would be stronger (of course they didn't consider weak TD2 or weaker Bonnie)...

[KWT]

I'd imagine you'd get more seasons like that from the 50s and 60s, with 10-13NS even in warm phase seasons but we could well still see some huge seasons IF that particular theory came off...

Its an interesting question though, I suspect stronger systems, less of them and forming further west due to stronger SAL outbreaks.

[Aric Dunn]

I'd imagine you'd get more seasons like that from the 50s and 60s, with 10-13NS even in warm phase seasons but we could well still see some huge seasons IF that particular theory came off...

Its an interesting question though, I suspect stronger systems, less of them and forming further west due to stronger SAL outbreaks.

well cant be sure about the sal outbreaks.. but keep in mind that shear plays a huge role in the initial development of many tropical systems as it helps aid in the initial development of convection that otherwise would be inhibited by subsidence

[Pearl River]

This is from Klotzbach in the most recent forecast:

There has, however, been a large increase in Atlantic basin major hurricane activity since 1995 in comparison with the prior 15-year period of 1980-1994 (Figure 19) and the prior quarter-century period of 1970-1994. It has been tempting for many who do not have a strong background in hurricane knowledge to jump on this recent 15-year increase in major hurricane activity as strong evidence of a human influence on hurricanes. It should be noted, however, that the last 15-year active major hurricane period of 1995-2009 has, however, not been more active than the earlier 15-year period of 1950-1964 when the Atlantic Ocean circulation conditions were similar to what has been observed in the last 15 years. These conditions occurred even though atmospheric CO2 amounts were lower in the earlier period.
Figure

[KWT]

well cant be sure about the sal outbreaks.. but keep in mind that shear plays a huge role in the initial development of many tropical systems as it helps aid in the initial development of convection that otherwise would be inhibited by subsidence

Indeed and thats why its such a tough call...of course if the desertification process continues then there will be a large region that is adding to the SAL. Of course in most years that isn't an issue past mid August to any great extent....

[Frank2]

Here in South Florida the loss of half the Everglades over the past 100 years has lead to a "urban desert effect" that was studied by some folks at CSU during the 1980's, and it makes sense since vegetation makes for daily transpiration - but cemet only creates evaporation of any moisture that lands on it, and once dry only aids in the dry heating of the atmosphere...

P.S. I always (and I mean always) cringe when seeing the VIS of South Florida - that strip of cement stands out like a sore thumb (ugh) and is easily seen from space...

http://sofia.usgs.gov/pubt/outgoing/sfl ... dpixsm.jpg

Frank