After all, on Earth, and especially on the gas giant planets like Jupiter and Saturn, weather is confined to thin, flattish slabs of atmosphere. Large patterns like hurricanes or the Gulf Stream — and Jupiter’s huge horizontal cloud bands and Great Red Spot—might all be feeding on energy from smaller scales. In the last few years, researchers analyzing winds both on Earth and on other planets have detected signatures of energy flowing to larger scales, the telltale sign of two-dimensional turbulence. They’ve begun mapping the conditions under which that behavior seems to stop or start.

The hope, for a small but dedicated community of researchers, is to use the quirky but simpler world of two-dimensional fluids as a fresh entry point into processes that have otherwise proved impenetrably messy. “They can actually make progress” in two dimensions, said Brad Marston, a physicist at Brown University, “which is more than what we can say for most of our turbulence work.”

Up in the Air

On Sept. 14, 2003, the National Oceanic and Atmospheric Administration sent an aircraft into Isabel, a Category 5 hurricane bearing down on the Atlantic Coast with winds gusting to 203 knots—the strongest readings ever observed in the Atlantic.

NOAA wanted to get readings of turbulence at the bottom of a hurricane, crucial data for improving hurricane forecasts. This was the first—and last—time a crewed aircraft ever tried. At its lowest, the flight skimmed just 60 meters above the churning ocean. Eventually salt spray clogged up one of the plane’s four engines, and the pilots lost an engine in the middle of the storm. The mission succeeded, but it was so harrowing that afterward, NOAA banned low-level flights like this entirely.

About a decade later, David Byrne got interested in these data. Byrne, a physicist at the Swiss Federal Institute of Technology Zurich, had previously studied turbulent energy transfer in lab experiments. He wanted to see if he could catch the process in nature. He contacted Jun Zhang, an NOAA scientist who had been booked on the very next flight into Isabel (a flight that never took off). By analyzing the distribution of wind speeds, the two calculated the direction in which energy was traveling between large and small fluctuations.

Starting at about 150 meters above the ocean and leading up into the large flow of the hurricane itself, turbulence began to behave the way it does in two dimensions, the pair discovered. This could have been because wind shear forced eddies to stay in their respective thin horizontal layers instead of stretching vertically. Whatever the reason, though, the analysis showed that turbulent energy began flowing from smaller scales to larger scales, perhaps feeding Isabel from below.

Their work suggests that turbulence may offer hurricanes an extra source of fuel, perhaps explaining why some storms maintain strength even when conditions suggest they should weaken. Zhang now plans to use uncrewed flights and better sensors to help bolster that case. “If we can prove that, it would be really amazing,” he said.

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On Jupiter, a much larger world with an even flatter atmosphere, researchers have also pinpointed where turbulence switches between two-dimensional and three-dimensional behavior.