Hurricane Irma’s devastation

The Caribbean lies in ruins and Florida in the USA licks her wounds after record-smashing Hurricane Irma

HURRICANE Harvey had barely blown itself out when an even more menacing phenomenon was on its way: Irma the Incredible, a record-busting category 5 hurricane packing the kind of power the world hadn’t seen for decades.

First it laid waste to a string of Caribbean islands, tossing boats around like toys and ripping buildings apart before making a beeline for Florida. Authorities didn’t mince their words when it came to Florida residents: get out now or you’re on your own.

By the time the monster hit the Caribbean, Irma had swollen to an area larger than France. The islands and the south of the United States are no stranger to hurricanes. But this was something else.

Irma was no respecter of privilege. While countless islanders lost their homes, British billionaire Richard Branson’s luxury home on Necker Island in the British Virgin Islands was also destroyed. The 67-year-old tycoon holed himself up in his wine cellar to ride out the storm, then travelled to Puerto Rico to coordinate a rebuilding plan and help relief efforts.

Dramatic before and after pictures show the extent of the disaster and the magnitude of the repair efforts needed.

Why this one was so deadly

Irma was the first storm in recorded history to maintain top winds of nearly 300km/h for 37 straight hours.

The hurricane was so powerful it temporarily sucked the ocean away from beaches in the Bahamas and Florida, stranding marine life on the shore.

Evacuees in Florida were warned not to return home after the wind died down because strong storm surges of up to 5m were predicted around the coast.

Like many Atlantic hurricanes, Irma originated near the Cape Verde islands off Africa’s northwest coast. Cape Verde storms have the capacity to become supercharged because of the long trek they make across the equatorial Atlantic before running into land and weakening, says meteorologist Neal Dorst.

A perfect storm of ingredients conspired to turn Irma into the beast she became. A combination of weak winds in the Atlantic, warm ocean temperatures and the fact that the core of the storm was able to remain over the open water without making landfall all led to the hurricane’s catastrophic power.

The wind shear over the Atlantic Ocean has been low this year, compared with previous years. Wind shear, a change in wind speed or direction with height, tends to rip a hurricane apart. When conditions are relatively tranquil, “cyclogenesis” can occur – which basically means a hurricane can form.

With exceptionally low wind shear over the Atlantic and Caribbean, the stage was set months ago for a terrifyingly active hurricane season.