Did Global Warming Cause the Katrina Levee Breaks!?

August 14- The work of hurricane expert Dr. Kerry Emanuel indicates that Global Warming provided the extra margin of energy that gave Hurricane Katrina enough power to break the levees in New Orleans. This is the conclusion of scientists, Global Warming observers along the Gulf Coast and others.

Hurricanes get their strength directly from the heat in the oceans they travel over, so it has long been expected that Global Warming would have an effect on the frequency and/or the intensity of tropical cyclones, which are called hurricanes in the United States. Observations have confirmed a sharp increase in intensity. The result is that the number of dangerous Category 3, 4, and 5 storms has increased. Dr. Emanuel's innovation, the “power dissipation index,” helps track this intensification over time.

“The increased danger from hurricanes is the perfect example of how Global Warming affects us. Global warming might not make hurricanes, it makes hurricanes stronger. When you add that to conditions that are uncertain anyway, such as weak levees, then the stronger storm can tip the whole situation into catastrophe,” said John Atkeison. Mr. Atkeison is Director of Climate and Clean Energy Programs at the Alliance for Affordable Energy in New Orleans.

Speaking on a webinar earlier this year, Dr. Emanuel, a professor at the Massachusetts Institute of  Technology confirmed the direct connection between hotter sea surface temperatures and stronger storms like hurricanes. He displayed the comparison between direct observations of Katrina's power and computer simulations of that storm in 1980 and 2005. The simulations used the actual conditions of the atmosphere and oceans to give the most accurate picture of the storm's development.

“We can't say that Hurricane Katrina was caused by global warming, but it did cause Katrina to be more intense,” Dr. Emanuel said. “We can do some interesting experiments to ask with respect to Hurricane Katrina, if that exact same storm had occurred in 1980, what that would have been like... In a computer simulation done with the thermodynamic environment of 1980, Katrina makes landfall not at 138 knots, but at something like 115 knots which might not sound like a lot of difference, but it makes a huge difference in destructive power. Probably if Katrina had occurred in 1980, the levees would have held.”

“I chose 1980 because it was the earliest year for which I trust the re-analysis data used to calculate potential intensity,” said Dr. Emanuel.

Global warming activists point to Dr. Emanuel's work as further evidence of the dangers of the climate changes caused by global warming. There is no top limit to the increases in wind speeds caused by hotter ocean temperatures, for example. Other climate changes currently underway are shifts in rainfall patterns and melting of glaciers, both of which threaten water supplies that are crucial for agriculture and for human consumption. Glacial melting also contributes to rising sea levels which adds to stress on endangered wetlands that form part of the natural storm buffers that have helped protect areas like the Gulf Coast in the past.

Activists have called for citizens to contact their U.S. Senators during the August recess to urge them to strengthen the climate legislation pending in the Senate. “No representative of the people should vote to put the short-term interests of the fossil fuel industries ahead of the future of the people and the country, said Mr. Atkeison.

The webinar was presented by the Southern Alliance for Clean Energy (http://www.cleanenergy.org/) and the Gulf Restoration Network (http://healthygulf.org/) SlideCast prepared by John Atkeison of the Alliance for Affordable Energy (http://all4energy.org/)  

The webinar can be viewed at
http://www.slideshare.net/jatkeison/emanuel-webinar-2009