How busy will Atlantic hurricane season be? Depends on who wins unusual battle of climatic titans

Two clashing climatic behemoths, one natural and one with human fingerprints, will square off this summer to determine how quiet or chaotic the Atlantic hurricane season will be.

An El Nino is brewing and the natural weather event dramatically dampens hurricane activity. But at the same time record ocean heat is bubbling up in the Atlantic, partly stoked by human-caused climate change from the burning of coal, oil and gas, and it provides boosts of fuel for storms.

Many forecasters aren’t sure which weather titan will prevail because the scenario hasn’t happened before on this scale. Most of them are expecting a near-draw. And that includes the National Oceanic and Atmospheric Administration, saying there’s a 40% chance of a near-normal season, 30% chance of an above-average season and a 30% chance of a below-normal season.

The federal agency Thursday announced its forecast of 12 to 17 named storms, five to nine becoming hurricanes and one to four powering into major hurricanes with winds greater than 110 mph. Normal is 14 named storms, with seven becoming hurricanes and three of them major hurricanes.

No matter how many storms brew, forecasters and Federal Emergency Management Agency Director Deanne Criswell reminded U.S. coastal residents from Texas to New England and people in the Caribbean and Central America that it only takes one hurricane to be a catastrophe if it hits you.

The two forces couldn’t be more opposite.

El Nino is a natural temporary warming of the Pacific that happens every few years and changes weather worldwide. Climate models predict as the world warms, El Ninos get stronger.

Decades of observation show that generally the Atlantic is quieter with fewer storms during El Nino years. El Nino’s warmer waters make warmer air over the Pacific reach higher up in the atmosphere, influencing winds and creating strong upper level winds that can decapitate storms, killing them, Klotzbach said. It’s called wind shear.

El Nino’s effects are not direct and “it’s not as in-your-face as a very warm ocean,” said University of Miami hurricane researcher Brian McNoldy.