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Old 11-30-2007, 11:55 AM
adios adios is offline
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Default Of Climate Models and Hurricane Predictions

For 2006 the National Oceanic and Atmospheric Administration (NOAA) made the following predictions regarding the hurricane season in 2006 prior to 2006:

NOAA PREDICTS VERY ACTIVE 2006 NORTH ATLANTIC HURRICANE SEASON - Residents in Hurricane Prone Areas Urged to Make Preparations

"For the 2006 north Atlantic hurricane season, NOAA is predicting 13 to 16 named storms, with eight to 10 becoming hurricanes, of which four to six could become 'major' hurricanes of Category 3 strength or higher," added retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator.

The record?

Climate of 2006 - Atlantic Hurricane Season
For the season, there were 5 hurricanes (2 major) and 4 tropical storms: a below-average season when compared with the recent 1995-2005 average, yet similar to the average of the preceeding 25 years (1970-1994) listed in the paragraph above. Only 2 storms made landfall with the mainland U.S. during 2006, Tropical Storm Alberto in Florida and Hurricane Ernesto as a tropical storm in Florida and North Carolina. For additional information on individual storms, please see the summaries below. For statistics on the Atlantic storm season, please see NCDC's 2006 Atlantic basin Tropical Cyclone page. [/b]

Does the NOAA rely on climate models to make their predictions?
Modeling Climate

I note the following from their description:

The accuracy of climate models is limited by grid resolution and our ability to describe the complicated atmospheric, oceanic, and chemical processes mathematically. Much of the research in OAR is directed at improving the representation of these processes. Despite some imperfections, models simulate remarkably well current climate and its variability. More capable supercomputers enable significant model improvements by allowing for more accurate representation of currently unresolved physics

I've maintained in these threads that the climate models are unproven to which wacki has shall we say disagreed. What he overlooks seemingly very often is that I've also stated that the development of climate models is a very worthwhile activity. Also what he seems to me anyway to conviently overlook is that I've stated that I believe that climate models in 50 years will have advanced a great deal. Probably more than we can imagine. So to summarize, climate modeling is a worthwhile activity in it's early stages of development, the models will continue to improve, and are likely to be very, very much more refined and accurate 50 years from now. Does the above statement by NOAA really contradict what I'm saying? Even the NOAA claims the accuracy of the models is limited. Don't know why wacki claims that uncertain accuracy doesn't mean the models predictive value is unproven.

I thought it might be interesting to look at the NOAA predictions for 2007:

NOAA: 2007 Atlantic Hurricane Season Outlook Update

NOAA is predicting a very high likelihood (85% chance) of an above-normal 2007 Atlantic hurricane season, a 10% chance of a near-normal season, and only a 5% chance of a below-normal season, according to a consensus of scientists at the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center, National Hurricane Center, Hurricane Research Division, and Hydrometeorological Prediction Center.

The outlook calls for an even higher probability of an above-normal season than was predicted in May (75%), and reiterates the expectation for a sharp increase in activity from the near-normal season observed last year. The 2007 season is expected to become the tenth above-normal season since the current active hurricane era began twelve years ago (in 1995). See NOAA’s definitions of above-, near-, and below-normal seasons.

The 2007 outlook calls for a likely range of 13-16 named storms, 7-9 hurricanes, and 3-5 major hurricanes. The likely range of the ACE index is 140%-200% of the median. These ranges are slightly tighter than those predicted in May (13-17 named storms, 7-10 hurricanes, 3-5 major hurricanes, and an ACE range of 125%-210%). The tighter ranges reflect not only an increased confidence for an above normal season, but also a reduced likelihood of seeing as many as 10 hurricanes and 17 named storms.


So what was the record?

Season Ends, Questions Remain

As a whole, the 2007 Atlantic hurricane season produced a total of 14 namedstorms, including six hurricanes, two of which became major hurricanes. NOAA'sAugust update to the seasonal forecast predicted 13 to 16 named storms - ofwhich seven to nine would be hurricanes, including three to five majorhurricanes of Category 3 strength or higher. An average season has 11 namedstorms, with six becoming hurricanes, including two major hurricanes. "The 2007 Atlantic hurricane season produced the predicted number of namedstorms, but the combined number, duration and intensity of the hurricanes didnot meet expectations," said Gerry Bell, Ph.D., lead seasonal hurricaneforecaster at NOAA's Climate Prediction Center. "The United States wasfortunate this year to have fewer strong hurricanes develop than predicted.Normally, the climate patterns that were in place produce an active, volatilehurricane season."The climate patterns predicted for the 2007 hurricane season - an ongoingmulti-decadal signal (the set of oceanic and atmospheric conditions that havespawned increased Atlantic hurricane activity since 1995) and La Nina -produced the expected below-normal hurricane activity over the eastern andcentral Pacific regions. However, La Nina's impact over the Atlantic wasweaker than expected, which resulted in stronger upper-level winds andincreased wind shear over the Caribbean Sea during the peak months of theseason (August-October). This limited Atlantic hurricane formation during thatperiod. NOAA's scientists are investigating possible climate factors that mayhave led to this lower-than-expected activity.All in all, one hurricane, one tropical storm and three tropical depressionsstruck the United States: Tropical Depression Barry came ashore near TampaBay, Fla., on June 2; Tropical Depression Erin hit southeast Texas on August16 and Tropical Depression Ten came ashore along the western Florida panhandleon Sept. 21; Tropical Storm Gabrielle hit east-central North Carolina on Sept.9, and Hurricane Humberto hit the upper Texas coast on Sept. 13. Also this year, the U.S. was reminded of the dangers of inland flooding. "Texas and Oklahoma experienced deadly flooding when Erin dumped up to 11inches of rain. Fresh water flooding is yet another deadly aspect of tropicalcyclones," said Ed Rappaport, acting director of NOAA's National HurricaneCenter.Other noteworthy statistics of the season include:


Again I'm not trying to denigrate the efforts of the scientists here. I'm just saying that the science is relatively new and probably will advance a great deal over time. I think accounts like the above show that this is the case. I'd like to point out another article from NOAA:

CLIMATE MODELS SUGGEST WARMING-INDUCED WIND SHEAR CHANGES COULD IMPACT HURRICANE DEVELOPMENT, INTENSITY

Global climate model simulations for the 21st Century indicate a robust increase in vertical wind shear in the tropical Atlantic and East Pacific Oceans, which could act to inhibit the development or intensification of hurricanes in these regions. Historically, increased vertical wind shear has been associated with reduced hurricane activity and intensity. (Click NOAA image for larger view of global warming’s multiple influences on hurricanes. Click here for high resolution version. Please credit “NOAA.”)

This new finding is reported in a study by scientists at the NOAA Geophysical Fluid Dynamics Laboratory in Princeton, N.J., and the Rosenstiel School of Marine and Atmospheric Science at the University of Miami, scheduled to be published April 18 in Geophysical Research Letters.

While other studies have linked hurricane intensity to global warming, this is the first published study to indicate that changes to vertical wind shear seen in future climate projections would likely diminish the frequency and intensity of hurricanes. Some effects of global warming, such as coral bleaching and melting tundra, are better understood than the impact on hurricanes.



Again this is not a denigration of the scientific efforts put forth and in fact I commend the efforts. Again I think it's fair to say that the we've got a lot to learn about modeling the climate and also that we're making progress.

My gripe is with the politicians that exploit the work of climate scientists to acheive their political agenda. I submit that if Al Gore made a movie that stated we need to arrest global warming because of increased vertical windshear he wouldn't have had many people listen to him.
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