22 | NewScientist | 3 November 2018HURRICANE Michael was a big
one. Intensifying faster than
expected, its 250-kilometres-per-
hour winds were just short of
Category 5 strength, making it the
fourth most powerful hurricane
to hit the US mainland since
records began.
The building codes in the
Florida panhandle, where Michael
made landfall on 10 October, are
designed to protect only againstwinds of 180 kilometres an hour.
Most houses were built long
before even these codes were
introduced. In seaside towns
such as Mexico Beach, below,
the winds and storm surge left
few buildings standing.
Michael is just the latest in a
series of extraordinary tropical
storms around the world (see
“Trails of destruction”, right).
“It’s been pretty shocking,” says
hurricane expert Jeff Masters
of online information service
Weather Underground.These storms are not just
stronger, as climate scientists
have long predicted for a warming
world. They are also forming and
moving over regions far beyond
their normal range, as well as
producing more rainfall and
higher surges, and strengthening
more rapidly, giving us less
warning of their arrival.
“There are many reasons to be
concerned,” says atmospheric
scientist Adam Sobel at Columbia
University, New York. “We are not
as prepared as we should be.”Tropical storms are fuelled by
the evaporation of warm water
from the ocean surface. Hurricane
season peaks in the northern
hemisphere from August through
to October, when the oceans are
at their warmest.
There are relatively few
hurricanes each year, a lot of
variability from year to year and
problems with our records – for
instance, some storms may have
been missed before satellite
records began in the 1970s. For
those reasons, there is still someINSIGHT HURRICANES
Kicking up storms
Tropical storms are becoming more intense and less predictable – and there
is little doubt remaining that we are to blame, says Michael Le PageJOE RAEDLE/GETTY
Mexico Beach, Florida, was largely
wiped out by Hurricane Michael