PHILADELPHIA - That the record-setting tropical storm traffic in the Atlantic Basin is going to persist is all but a given, forecasters say. The deeper and more frightening question is, Will any of the storms become monstrously destructive hurricanes and when will we know it?
As they relearned in August with Laura, whose winds doubled from 75 to 150 mph in 36 hours, the answers might not come until the hurricane is on the very doorstep of a heavily populated coast. Track forecasts have improved significantly, but the National Oceanic and Atmospheric Administration acknowledges that predictions of intensity changes haven't kept pace.
The riddles remain as elusive as the inner lives of the oceans, related to things as prosaic as salt and ocean spray, and as cosmic as the behavior of the Amazon, Orinoco, and the Mississippi.
While researchers have known that those three mighty rivers are rich sources of freshwater that layer hurricane-spawning grounds with the equivalent of lighter fluid, only in recent years have they escalated their efforts to find out what's going on below the surface.
They include dispatching an armada of robot submarines, an initiative spurred in part by Hurricane Sandy, which devastated parts of the Jersey coast and caused tremendous damage across the Philadelphia region.
"We realized the last few years we have to deal with the problem, we can't just deal with the atmosphere," said Frank Marks, director of NOAA's Hurricane Research Center. "The ocean observations are quite a number of years behind what they are in the atmosphere."
"You need to know more than the surface," said Gustavo Jorge Goni, director of NOAA's physical oceanography division, which is deeply involved in the escalating efforts to probe the secrets of the Atlantic, the Caribbean Sea, and the Gulf of Mexico. "You need to know what's under surface."
Based on the forecasts, more case-study opportunities are coming.
Already 21 named storms, those with winds of 39 mph or better, have formed in the basin. Conditions remain favorable for more and the record of 28, set in 2005, is in serious trouble.
Researchers don't know all the factors that cause a tropical storm to mutate into an explosive hurricane.