A team of researchers has turned to the ocean to help unravel the mysteries of cloud formation by peeling back the mysteries of the structures of tiny aerosol particles at the surface of the ocean.
The University of Wisconsin-Madison work shows how the particles’ chemical composition influences their abilities to take in moisture from the air, which indicates whether the particle will help to form a cloud, a key to many basic problems in climate prediction.
To understand the Earth’s climate, scientists must consider and measure both human-made environmental pollutants and naturally occurring processes that influence how much energy the planet absorbs from the sun or radiates back into space. One naturally occurring process that plays a big role in this delicate balance is the formation of clouds.
Timothy Bertram’s group focuses on areas where chemistry significantly affects climate or the environment. And because oceans cover more than 70 percent of the Earth’s surface, the researcher has focused on the ocean surface in order to better understand an important piece of the larger climate picture.
While the emission of particulates from the ocean isn’t nearly as strong as that from trucks, the majority of the Earth’s surface is not covered by trucks, Bertram noted that the ocean may be a diffuse source (of these particles), but it’s a very important source.
In their new work, Bertram and colleagues’ investigation began in a laboratory-based wave channel, which allowed them to replicate the types of sea spray aerosol particles found near ocean waves. They also studied particles from the actual ocean-air boundary. By mimicking ocean waves and sea spray in the wave channel, the researchers could gain insight into the structures and cloud-formation potential of particles in the open ocean.
The study appears in ACS Central Science.