Why, when the trade winds stop blowing in Honolulu, New York City gets a winter like Seattle’s.

(Photo: Illustration by Wesley Bedrosian)

(1.) For reasons that remain a bit mysterious, every two to seven years the trade winds of the equatorial Pacific, which go west to east, stop blowing hard for a year or two.

(2.) Without an easterly pushing the current, the surface of the warm water of Indonesia backs up all the way across the equator to the Americas.

(3.) Warm, wet Pacific air rises high into the atmosphere and energizes the jet stream, which blows west to east across North America.

(4.) The jet stream drags this warm, wet air to New York City, resulting in a mild but wet winter more typical of the Pacific Northwest than of here.

(5.) Meanwhile, in the waters off the Eastern Seaboard, the Atlantic Multidecadal Oscillation heats up the ocean, giving more energy than usual to the hurricanes that form there.

(6.) But the jet stream, flush with energy from the Pacific, continues into the Atlantic, and pushes those hurricanes away from Northeastern shores.

Related:

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• Articles by Clive Thompson
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