Warming world blamed for more strong hurricanes
Just saw this in New Scientist. Warming world blamed for more strong hurricanes.
According to the article, a massive global increase in the number of strong hurricanes over the past 35 years is being blamed on global warming.
In the most detailed study yet, US scientists warn that Katrina-strength hurricanes could become the norm.
Hurricanes form when ocean temperatures rise above 26°C. “The fuel for hurricanes is water vapour evaporating from the ocean surface. It condenses in the air and releases heat, which drives the hurricane’s intensity,” says Peter Webster of the Georgia Institute of Technology, Atlanta. He adds, “the trend is global, has lasted over several decades and is connected to a steady worldwide increase in tropical sea temperatures.”
“The tendency to Katrina-like hurricanes is increasing,” says Greg Holland of the National Center for Atmospheric Research (NCAR) at Boulder, Colorado. Without the warmer sea-surface temperatures, “Katrina might only have been a category 2 or 3”.
All the data for sea surface temperatures and hurricane numbers and intensities come from satellite data. “We deliberately limited this study to the satellite era because of the known biases [in the data] before this period,” says Webster.
This is the third report in recent months highlighting the growing risk to life and property round the world from hurricanes and tornadoes. In June, NCAR’s Kevin Trenberth reported a rising intensity of hurricanes in the North Atlantic.
And in August, Kerry Emanuel of MIT found a 50% increase in the destructive power of tropical storms in the past half century.
