A new study could tell us more about the shape of water.

Mike Larsen (Photo by Heather Moran)

College of Charleston physics professor Mike Larsen is working on a project that has allowed him to measure the 3-D statistical structure of water drops in clouds. These cloud droplets grow by the diffusion of water vapor before collisional growth turns the tiny droplets into drizzle and rain.

Using an aircraft-mounted holographic cloud particle imaging device, Larsen and his collaborators were able to fly inside clouds to get real-time measurements of water droplet clustering. By using this method, they were able to record and analyze individual cloud droplet positions to determine the degree of cloud particle clustering. Previous research had to be conducted in laboratory settings.

“This is the first time that a fully three-dimensional statistical measurement of this clustering has been made for natural clouds,” says Larsen. “The results show evidence of cloud-particle clustering consistent with numerical simulations and laboratory experiments conducted under turbulence conditions significantly different from the natural atmosphere.”

This research has far-reaching implications for improving our understanding about how particles interact with turbulent motions and may have applications in areas as varied as planet formation, fuel spray in a combustion chamber and rain formation.

The study was recently published as an editor’s suggested article in the journal Physical Review Letters.