Even as seas warm, for example, accelerating high-level winds can shred the towering cloud formations of a tropical storm.

"The high-level winds direct the storms, but they have their own low-level circulations," he explained.

The other was wind shear produced when high-level winds from the Pacific encounter storms moving across the Atlantic toward the United States.

This second storm not only competed for energy; its high-level winds also clashed with those of the hurricane.

The eruption injected an unusually large amount of sulfur dioxide (SO) gas high into the stratosphere, which was subsequently transported by high-level winds all over the planet.

Some of these equatorial aerosols may also be transported by high-level winds to other parts of the world, Dr. Ramanathan said, but this has not been established.

After Tropical Depression Barry emerged from central Florida, it was still under pressure from high-level winds.

The main problem was high-level winds that often pushed the balloons out of range of radio communications with the ground.

"If high-level winds are strong and from the west, tropical storms don't do so well," he said.

When it is in place, high-level winds blowing from the west tend to shear off the tops of developing hurricanes in the adjacent Atlantic, causing them to abort.