Good news for fans of hurricane swell, but very bad news for most every body else who lives anywhere near where hurricane damage is a dire threat—Hurricanes, all over the world, are slowing way down, according to a study released last week in the journal Nature.
This doesn't mean the sustained winds in hurricanes and tropical storms are lessening; the storms themselves are wandering their paths through the sea and over land at a much lazier pace than in decades past. Data for this study shows that storms have been slowing since the 1940s.
On average, hurricanes are moving 10 percent slower across the world, though in section of the Pacific, they're lazing about at a pace 20 percent slower than researchers expect.
Obviously, the longer a storm sits in one place, the more damage it can generate as the punishing winds and storm surges and tremendous surf unleashed from one of these tropical beasts carries on for much longer.
Hurricane Harvey, which thoroughly annihilated much of the Texas Gulf Coast last year while also flooding Houston, is an example of a storm that just sort of sat there and raged and raged for longer than it should have, historically speaking.
Why? Nobody really knows, though a warming climate is thought to play a role. Warmer atmospheric temps slow down global air circulation. Nathan Cool, meteorologist, surf forecaster, thinks the slowing might be because we're in the middle of an El Niño/La Niña cycle, which can wreak its own special kind of havoc.
"When El Niño backs off, so do hurricane-killing winds (known as wind shear), thus allowing hurricanes to grow stronger, and also move slower," says Cool. "Everyone thinks 'El Niño El Niño El Niño' when it comes to surf, but a prolonged neutral state can mean so much more — not just for surf, but weather as well. We entered a neutral El Niño in 2016, which kicked off a whole slew of record breaking events…surf, flood, fire and mud."
When a massive fetch-generation storm like a hurricane sits in one spot for awhile, the duration of strong winds across that fetch will make some really big waves. Slower storms, therefore, make bigger swells than fast-moving storms.
With no reason to expect the slowing to reverse itself anytime soon, hurricane swells could very likely be historically large in coming years. Maybe keep that in mind when ordering summer boards.