New Wave Discovery
The uncovering of a new type of wave may have a ripple effect in the Earth and planetary sciences, says the scientist from the Cooperative Institute for Research in Environmental Sciences (CIRES) who discovered the wave.
“It is completely unexpected—the wave type is unusual in several respects,” said CIRES Senior Research Scientist Oleg Godin, whose finding was published May 9 in Physical Review Letters. “It just flies in the face of what we teach students.”
Both in water and air, waves can vary in height—amplitude—and in length—wavelength. These waves, which can range from less than a centimeter in length to thousands of kilometers, play a key role in transferring energy both within and between the ocean and the atmosphere. “In this way, to a large degree waves control weather and climate,” Godin said.
Previously, while a collection of mathematical solutions have explained the impact of variables such as a fluid’s buoyancy and compressibility on how waves move through fluids, they don’t fully describe the diversity of the wave types. The new wave, with its simple and exact mathematical description, will grant scientists greater understanding of how waves transfer energy through the environment and the subsequent climatic implications.
“The discovery has uncovered a new mechanism of coupling between physical processes in the ocean and the atmosphere,” Godin said. “The new wave gives us an opportunity to really understand some aspects of what is going on.”
The new wave type comes with some unique quirks, Godin said. While the wave can move through fluid at speeds close to, or greater than, the speed of sound, motion does not compress the fluid. Another unusual characteristic is that the vertical structure of the fluid motion is independent of sound speed and density variation in the fluid, he said.
This latter anomaly is one that may have implications for remote sensing, Godin said. It means the wave type is highly sensitive to background fluid velocity (such as wind velocity), and specific measurements taken of the new wave type can reveal a full wind profile without having to obtain knowledge of other properties such as the temperature field and other material parameters.
“This is particularly important for remote sensing of atmospheres on other planets, where we do not have a lot of information about their material properties,” Godin said.
Given there are very few tools to study large-scale motion in the atmospheres of planets, the new wave type may prove a valuable asset to scientists, he said. “It allows you to probe different aspects of the atmosphere,” he said.