WASHINGTON DC, USA, May 23, 2007 – American government scientists are predicting an above average hurricane season this year.
The forecast, released yesterday in a news conference just outside of Washington DC, was consistent with that of noted private sector forecasters Professor Bill Gray and Bill Klotzbach of the Colorado State University as well as hurricane researchers at the Benfield University College of London Hazard Research Centre in the UK.
Held in an aircraft hangar on which the high level Gulfstream IV hurricane research jet of the National Oceanic and Atmospheric Administration (NOAA) was on display officials said that all the ingredients for an upsurge in hurricane activity this year are in force.
The ingredients are not global warming but the usual set of ongoing multi-decadal signals: a favourable African easterly jet stream, warmer-than-normal sea surface temperatures, reduced wind shear, and lower surface pressures in the Caribbean.
“For the 2007 Atlantic hurricane season, NOAA scientists predict 13 to 17 named storms, with seven to 10 becoming hurricanes, of which three to five could become major hurricanes of Category 3 strength or higher,” said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator. An average Atlantic hurricane season brings 11 named storms, with six becoming hurricanes, including two major hurricanes.
Lead forecaster Dr Gerry Bell of NOAA’s Climate Prediction Center said that Subtropical Storm Andrea in early May which formed in early May was not an indication of what was to come. With or without Andrea, he said, the forecast is one of an above normal season.
However he did say that there was some uncertainty as to whether or not a La Nina will for and how strong it will be.
“The Climate Prediction Center is indicating that La Nina could form in the next one to three months. If La Nina develops, storm activity will likely be in the upper end of the predicted range, or perhaps even higher depending on how strong La Nina becomes. Even if La Nina does not develop, the conditions associated with the ongoing active hurricane era still favor an above-normal season.”
A strong La Nina tends to enhance hurricane activity while a strong El Nino has the opposite effect.
Professor Gray and Klotzbach last month forecast 17 named storms, 9 hurricanes, and 5 major hurricanes.
The Benfield Hazard Research Centre has forecast 16 storms, nine hurricanes, and four major hurricanes.