Dear Margaret, Can you inform us about the impact of hurricanes on transport of water vapor and other gases to the upper troposphere/lower stratosphere (UT/ LS)?
Sincerely, Oliver Wingenter On Jun 2, 11:38 am, Margaret Leinen <[email protected]> wrote: > Alvia, > > You are correct that hurricanes and tropical cyclones move heat. It was not > clear from your answer whether you were saying that you doubted that they > mattered much for heat dissipation on a global scale or whether you were > saying that you doubted that they mattered much for heat transport. They > are actually an important mechanism for the latter. Estimates based on > observations incorporated into models suggested that ocean heating induced > by topical cyclones could be as much as 1.4 (± 0.7) × 10^^15 W for a single > year (Emanuel, 2001), a significant fraction of the observed peak poleward > heat flux and enough to require consideration in the climate system. More > recent modeling by Hu and Meehl (Gerry may be on this list and is far more > authoritative on this topic than am I) (2009) also suggests that hurricanes > can strengthen the meriodional overturning circulation and may play an > important role in the climate system. > > Margaret > > On 6/2/09 1:12 PM, "Alvia Gaskill" <[email protected]> wrote: > > > > > As the article indicates, what hurricanes do is move heat around, not > > dissipate it. Whether this actually cools the planet is unknown. Given the > > relatively small number of all tropical cyclones and their short lifetimes > > of > > around a week or so, I doubt they matter very much on a global scale. > > Another > > theory has them increasing atmospheric CO2 by stirring up surface waters, > > although they may also reduce it by upwelling nutrients causing > > phytoplankton > > blooms. Global warming didn't stop because of all the storms in 2005 (the > > year of Katrina) and it didn't get worse in the subsequent years due to > > fewer > > storms. > > >http://dsc.discovery.com/news/2009/01/29/hurricane-climate-02.html > > > Hurricanes' Climate Footprint Felt for Months > > Michael Reilly, Discovery News > > > Jan. 29, 2009 -- Just as a changing climate shapes the strength and > > frequency > > of hurricanes, the storms may have a huge effect on climate, leaving > > "footprints" in the atmosphere and ocean. > > > Watch a video on hurricane-prone coastlines. > > > Hurricanes are infamous as harbingers of chaos -- flooding cities, ripping > > houses to shreds, destroying beaches and even whole islands. And concerns > > are > > growing that human-induced climate change may lead to stronger storms whose > > intensity will wreak even more havoc on coastal communities around the > > world. > > > But the full interplay between hurricanes and climate remains an enigma. > > > Robert Hart of Florida State University analyzed two decades of climate data > > from the tropics, and found that each storm leaves a wake of anomalously > > cool > > water and warm air behind it that can persist anywhere from one to two > > months, > > depending on the storm's strength. > > > Scientists have known for years that hurricanes cause cool ocean waters to > > well up, but Hart was surprised at how long the atmosphere retained a > > "memory" > > of each storm. > > > That got him thinking: if one storm can have such a lasting impact, what > > does > > a whole season of storms do to Earth's climate? Would there be a difference > > in > > effect between an active hurricane season and a quiet one? > > > Hart performed a series of calculations and came up with a striking > > preliminary answer: hurricane seasons that spawned more storms (like 2005, > > for > > example) led to quieter winters in the northern hemisphere, and quiet > > hurricane seasons led to winters with lots of storm activity. > > > The reason, Hart speculates, is that hurricanes bring large amounts of heat > > out of the tropics and toward the poles. When a season has more storms, more > > heat is deposited closer to the poles and the tropics are cooled off more, > > so > > that when winter sets in there is less temperature difference between the > > poles and tropics. > > > "That's what winter weather is -- movement of heat between the tropics and > > the > > poles," Hart said. "So it's possible that hurricanes do more than their fair > > share of the work during an active season, and there's less work to be done > > during the winter." > > > Gabriel Vecchi of the National Oceanic and Atmospheric Association's > > Geophyscial Fluid Dynamics Laboratory in Princeton, N.J., said Hart's work > > gets at some of the toughest questions in meteorology today: What are > > hurricanes? Do they serve a purpose? > > > "It may sound like a stupid question, but I wonder what tropical cyclones' > > role in the climate system is," he said. > > > There are two general theories -- one which states that hurricanes are > > simply > > the result of more potent forces, like El Nino pushing vast amounts of heat > > and moisture around Earth's atmosphere. The other says hurricanes are vital > > heat engines that transfer energy from the tropics toward the poles. Through > > their fury, they are in fact bringing balance to the planet's climate. > > > "The list of results about how they affect climate is getting longer," > > Vecchi > > said. "This is all hinting that tropical cyclones do something profound." > > > ----- Original Message ----- > > From: f.m.maugis > > To: [email protected] ; [email protected] > > Sent: Tuesday, June 02, 2009 11:30 AM > > Subject: RE: [geo] Just in Time for Hurricane Season > > > Why killing hurricanes, as far as they cool naturally our climate ? > > > François MAUGIS > > http://assee.free.fr > > =============================================== > > > ------------------------------------------------------------------------------ > > De : [email protected] > > [mailto:[email protected]] De la part de Alvia Gaskill > > Envoyé : mardi 2 juin 2009 01:09 > > À : [email protected] > > Objet : [geo] Just in Time for Hurricane Season > > > I was admittedly a little drowsy when I saw the promo for this, but it > > appears to be another incarnation of the ocean pipes idea or perhaps the > > same > > one from Atmocean. One problem for would be hurricane killers is that they > > seem to be appearing in places where they shouldn't, when they shouldn't and > > rapidly intensifying, giving little time to react. Thus, strategies that > > prevent the conditions that drive hurricane development should probably be > > considered before filling up the Gulf of Mexico and the Atlantic with > > plastic > > pipes. The cloud ships, the partial desert cover and the stratospheric > > aerosols all could be part of the first line of defense. > > >http://science.discovery.com/tv-schedules/series.html?paid=48.15725.2... > > 4.3 > > > NextWorld > > Future Danger > > TV-G > > > Future Danger enters a world where robots safeguard our cities, massive > > underwater heating and cooling systems break up hurricanes before they hit > > land, and advanced rocket interceptors protect the planet from asteroids > > that > > could wipe out humanity. > > > Air times in the U.S.: June 7, 9pm, June 8, 12am and June 9, 4 am. 60 > > minutes. > > -- > Margaret Leinen, PhD. > Climate Response Fund > 119 S. Columbus Street > Alexandria, VA 22314 > 202-415-6545 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. 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