Hurricanes: climate change won't make them stronger
There may be no connection between the warming of seawater due to climate change and an increase in the destructive power of tropical cyclones in the Atlantic.
According to a new study by the University of Virginia at Charlottesville, warmer seawater has contributed half to the increase in the number of stronger storms over the past 25 years, but has not changed their overall strength. The other fifty percent increase in numbers was also due to specific conditions in the atmosphere, but these vary in a naturally cyclical framework, the scientists said.
Patrick Michaels' research team had examined the water temperature along hurricane tracks. They found that a tropical storm does not develop into a higher-category hurricane on the Saffir-Simpson scale until a temperature threshold of 28 degrees Celsius is exceeded. After that, this or even higher water temperature no longer plays a decisive role in the further development of the hurricane and its final strength. The differences in air temperature and humidity as well as the vertical wind profile - i.e. the change in wind speed with distance from the sea surface - in the vicinity of the hurricane then have a greater influence.
However, Michaels expects that there will be more tropical cyclones in the future due to global warming. In terms of intensity, however, they will not be any stronger than in the past. The increasing number of hurricanes in the Atlantic in recent years can still be traced back, at least in large part, to a natural cycle that is related, among other things, to spatial changes in the important ocean currents. The hurricane seasons between 1930 and 1970 were similarly active, followed by a period of relative calm.