Which is when the weird weather begins—because all that moist, warm water evaporates into the air and produces spectacularly intense rain, winds, and storms. In the U.S., California is the first to get hit: The last big El Niño, in the winter of 1997–98, produced 40-foot-high waves, home- destroying landslides, and the 200-mph Hurricane Linda. The PGA amateur tournament was canceled when golf courses were reduced to mud pits; bewildered California fishermen began catching mahimahi and marlin, because the ocean became so warm that these normally tropical fish swam hundreds of miles north. “A really big El Niño,” says Vern Kousky, a government meteorologist who first announced the El Niño that formed this summer, “has just a huge, huge effect on everything.”
Yet the effect isn’t all bad. Indeed, a strong El Niño makes New York a much nicer place to live—balmier, and with less-violent weather. That’s because as the hot, wet air flows in off the Pacific, it amplifies the speed and intensity of the jet stream, the rivers of fast-moving air that flow toward the east across the country at 20,000 feet. And this more-powerful jet stream, in turn, affects weather all the way to the East Coast. As the jet stream shoots out over the Atlantic, for example, it produces wind shear that “tears hurricanes apart before they can form,” explains Phil Klotzbach, a hurricane predictor with the Tropical Meteorology Project at Colorado State University. Indeed, El Niño is probably the reason this year’s hurricane season has been so much less punishing than last year’s parade of tropical monsters.
What’s more, the amplified jet stream scoops up the milder weather of Washington State and drags it across the country. The current El Niño isn’t yet strong enough to have this effect, but Kousky predicts it could within a few months. “It takes Seattle’s weather,” Kousky says, “and brings it to New York.” During the particularly intense El Niño of 1997–98, not a flake of snow remained on the ground in Manhattan that winter—something that hadn’t happened in more than 100 years. When you’re sitting outside sipping a cappuccino on an unseasonably balmy March afternoon, you’ll have El Niño to thank.
You can also thank it for a lighter energy bill. Warm winters reduce the demand for oil, and the absence of killer storms keeps Gulf Coast oil-refinery production high. El Niño thus produces cheap oil—indeed, ten years ago, it actually helped cut the price of a barrel in half. This year’s El Niño won’t have quite that powerful a kick, but it’s already been credited with pushing the price of a barrel of oil below $60 for the first time in six months. This slump in prices means spectacularly bad news for the go-go hedge funds that have made their fortunes by betting on wartime oil shortages—such as Amaranth Advisors, the $9 billion fund that lost a mind-bending $6.5 billion in two weeks, then shut down in September. As the weather swings, so swings the energy market.
The fifties are here again.
Digging deeper into the meteorological forces that undergird our weather, I arrange to meet Heidi Cullen—the chief climatologist for the Weather Channel—at a Tribeca café on a recent stunning fall day, and she told me about her father. Her family is from Staten Island, and that’s where her father grew up in the fifties. The weather back then was a nonstop carnival of storms and hurricanes. The worst, Hurricane Donna in 1960, terrorized the entire Northeastern Seaboard, and by the time it wound up on Long Island, 364 were dead. So last year, when the tail ends of Katrina and a half-dozen other huge storms lashed New York, Cullen’s father didn’t find it particularly surprising.
“He was like, ‘You guys have no idea what it was like. There were so many big storms and hurricanes back when I was young,’ ” Cullen says. Only the brave lived on waterfront property.
And, as it turns out, her father’s weather has come back to haunt us: The storms of today eerily resemble those of the fifties. Why? Because of a climate pattern that is set to govern the skies of New York for the next twenty years: the Atlantic Multidecadal Oscillation (AMO).
The AMO is the enormously slow, powerful heartbeat of the Atlantic, a 70-year-long cycle in which the ocean slowly heats up and then cools down again. Scientists began to notice this pattern ten years ago, when they looked back over 150 years of records of the Atlantic’s surface temperature. For a period of 35 years, it would warm up by about one to two degrees; then it would gradually decline until it had cooled by the same amount, over roughly the same time. That difference in temperature doesn’t sound like much, but when you’re talking about a body of water as massive as the Atlantic, a two-degree shift represents an enormous amount of energy. Indeed, hurricanes typically begin forming when ocean water hits 78 degrees Fahrenheit, so every extra degree counts.