Scientists predict ‘above normal’ Atlantic hurricane season
“We are seeing an increase in the proportion of hurricanes reaching Major Hurricane Status, Category 3 and above,” said Dr Emanuel. “This is what we see unequivocally in satellite data.”
James Kossin, also with NOAA, has done research that further supports the idea that hurricanes are getting stronger. With the continued warming, he suggested, “you’ll start to see intensities like you’ve never seen before,” even storms packing 250 mph winds. (Major hurricanes, starting with Category 3, have wind speeds between 111 and 129 miles per hour. A Category 5 storm, currently the most powerful classification, is 157 mph and above.) “This is no It’s only a matter of time, ”he says.
Other research suggests that hurricanes can weaken more slowly after making landfall, increasing their destructive capacities, and that storms slow down, persist on approach and extend damage over longer periods of time.
Between the greater water vapor in the atmosphere and the slowdowns of storms, Dr Kossin said, there has been a 41 percent increase in local precipitation associated with storms moving across land. Also, he said, the storm tracks are moving away from the tropics and heading further north, with the storm risk range further expanding.
The strongest area of debate is whether climate change has a role in the increasing number of hurricanes in the Atlantic. Recent research suggests an important role for human actions, although not all of these actions are directly related to climate change.
The more conservative faction of scientists attributes much of the rising storms to natural variability and a warming and cooling cycle of the oceans known as the Atlantic Multidecadal Oscillation; NOAA scientists cited the phenomenon as one of the main factors behind last year’s increase in forecasts of an active season. Other climatologists, including Michael Mann of Pennsylvania State University, have questioned whether or not the oscillation exists.
MIT’s Dr Emanuel is among a growing body of scientists who say the surge in storm numbers in the Atlantic is man-made, but not primarily due to global warming. The fact that the number of storms fell in the 1970s and 1980s is largely linked to pollution, they say – in particular, sulfur air pollution floating over the Atlantic from Europe during the post-war boom that cleared up when environmental regulations began to clean up. in the heavens. “Almost certainly, the cyclonic drought of the 1970s and 1980s was an aerosol-related phenomenon,” Dr Emanuel said.
The result, he said, “reminds everyone that our influence on the climate goes beyond greenhouse gases.”
Christophe Flavelle contribution to reports.