Winds of change stir up near‐record hurricane season

Abstract

Perhaps in four or five years, if scientists can gather enough evidence to theorize that the great Atlantic Ocean Conveyor Belt is moving quickly again, they might consider 1995 a turning point in the recent history of hurricane trends. But until then, researchers will have to keep this year in the record book of hurricane anomalies.The conveyor‐like megacurrent that cycles water from the Indian and Pacific Oceans into the Atlantic and back—particularly warm water from the tropical Atlantic to the edge of the Arctic—seems poised to pick up its pace, according to hurricane researcher William Gray of Colorado State University. A quicker thermohaline conveyor belt, Gray believes, may be the driver behind the cyclical, decades‐long trends in sea surface temperatures that, by corollary, affect multi‐decadal storm patterns. “The conveyor belt has apparently been slowed down for 25 years,” Gray notes, a change that has coincided with more El Niño events, less rainfall in Africa, and stronger zonal winds. All three of those factors seem to be what Gray calls “proxy manifestations” of conveyor belt variability.