Saison cyclonique Atlantique 2006

[Invité]

Je suis d'accord avec toi, il va falloir du recul pour comprendre ce phénoméne , car même avec une anomalie positive en température pas le moindre signe de tempête tropicale .

En juillet 2006, si la SST de la zone de naissance des cyclones près des côtes occidentales et équatoriales de l'Afrique a été effectivement plus chaude qu'en 2005 (forte année comme chacun sait) par contre la zone de murissement des TT en cyclone a connu des SST plus faibles.

Il me semble que les SST de cette zone ne se sont jamais remises de l'intense saison 2005 qui leur a pompé pas mal d'énergie.

En conséquence il me semble qu'une forte année cyclonique voire exceptionnelle comme 2005 ne peut être que suivie d'une année faible.

De plus si des SST élevées sont souvent des éléments importants pour expliquer la force des cyclones il semble que le régime de vents et l'instabilité atmosphérique en soient d'autres pour expliquer la formation des TT.

[The Phoenix]

Voici une réponse à nos questions, suite à une mise à jour des perspectives de cyccones de la NOAA ont y voit un peu plus clair .

http://www.noaanews.noaa.gov/stories2006/s2678.htm

NOAA CONTINUES TO PREDICT ABOVE-NORMAL HURRICANE SEASON

August 8, 2006 — With the peak of the Atlantic hurricane season upon us, experts from NOAA are reiterating their prediction for an above-normal number of storms. NOAA scientists warn this year's relatively quiet start is not an indication of what the remainder of the season has in store. (Click NOAA image for larger view of updated 2006 Atlantic hurricane season outlook. Please credit “NOAA.”)

"This year's three named storms may pale in comparison to the record nine storms that formed through early August 2005, but conditions will be favorable for above-normal activity for the rest of this season—so we are not off the hook by any means," said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator.

News Conference Audio (mp3), National Press Club, Washington, D.C.

1) David Miller, NOAA Public Affairs, introduces speakers. :51 4) David Paulison opening statement. 1:58

2) Conrad Lautenbacher opening statement. 4:26 5) Max Mayfield opening statement. 4:08

3) Gerry Bell opening statement. 4:20 6) Q & A 23:15

News Conference Photos Podcast

For the entire 2006 season, which ends November 30, NOAA is projecting a total of 12 to 15 named storms of which seven to nine will intensify to hurricanes, including three or four becoming major hurricanes—rated at Category 3 or higher. This forecast is slightly lower than the outlook issued in May, but remains above the seasonal average of 11 named storms, six hurricanes and two major hurricanes. (Click NOAA image for larger view of contrasting conditions in 2005 and 2006 for tropical storm development. Please credit “NOAA.”)

According to Gerry Bell, Ph.D., NOAA's lead seasonal hurricane forecaster, the major climate factors expected to influence this year's activity are the ongoing multi-decadal signal, which produces wind and atmospheric pressure patterns favorable for hurricane formation, along with ongoing warmer-than-normal sea surface temperatures. NOAA attributes these same factors to the current active Atlantic hurricane era that began in 1995.

Bell noted that conditions were ripe last year for early season storm development. "La Niña-like convection in the central equatorial Pacific during June and July of 2005 contributed to the development of numerous early-season storms," he said. "Conditions this year reflect a more typical active season, with peak activity expected during August-October." (Click NOAA image for larger view of the expected conditions through October 2006 for tropical storm development. Please credit “NOAA.”)

NOAA's seasonal outlook, however, does not specify where and when tropical storms and hurricanes could strike. "Science has not evolved enough to accurately predict on seasonal timescales when and where these storms will likely make landfall," said Bell. "Exactly when and where landfall occurs is strongly controlled by the weather patterns in place as the storms approach land. These weather patterns generally cannot be predicted more than several days in advance."

"As we approach the peak of the hurricane season, our message remains the same, be informed and be prepared," said Max Mayfield, director of the NOAA National Hurricane Center. "Preventing the loss of life and minimizing property damage from hurricanes are responsibilities shared by all. Remember, one hurricane hitting your neighborhood is enough to make it a bad season." (Click NOAA image for larger view of the comparison of sea surface temperatures for July 2005 and July 2006. Please credit “NOAA.”)

In 2007, NOAA, an agency of the U.S. Commerce Department, celebrates 200 years of science and service to the nation. From the establishment of the U.S. Coast and Geodetic Survey in 1807 by Thomas Jefferson to the formation of the Weather Bureau and the Bureau of Commercial Fisheries in the 1870s, much of America's scientific heritage is rooted in NOAA.