In a study published today in ACS Central Science, a research team led by University of Wisconsin-Madison chemistry professor Timothy Bertram peels back the mysteries of the structures of tiny aerosol particles at the surface of the ocean.
The 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.
In order to investigate sea spray particles formed at the ocean-air boundary in nature, researchers used a 33-meter-long wave channel to replicate waves found in nature. They filled the wave channel, which is located at the Scripps Institution of Oceanography, with seawater from the ocean.
Courtesy of Christina McCluskey
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.
Clouds are made of tiny droplets of water. It has long been known that the droplets that make up clouds form around tiny nuclei -- grains of dust, salt or even microbial life.
Clouds help reflect solar energy back to space, but the process for a particle to seed a cloud can change depending on the natural setting. A particle must take up water from its surrounding environment in order to seed a cloud, but the particle's chemical composition may be very uniform or very diverse, affecting its ability to do so.
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 UW-Madison 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 says. '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 team then developed a new method that categorizes a diverse population of aerosol particles based on their likelihood of taking up water from the surrounding environment and forming a cloud. Previous approaches yielded one number to assess sea spray aerosol particles' ability to form clouds. The new method, however, provides a more precise measure by indicating the percentages of particles in each category, thus more properly accounting for particle-to-particle variability in cloud formation.
'The advancement is that this is general,' Bertram says. 'It's a framework people can use broadly to look at this question of the diversity of particulates and how they impact cloud formation.'
Collaborators include other researchers affiliated with the Center for Aerosol Impacts on Climate and the Environment at the University of California, San Diego; the University of Iowa; the Scripps Institution of Oceanography; and the University of California, Davis, as well as a researcher from NOAA's Pacific Marine Environmental Laboratory. Steven Schill, a graduate student in the Bertram group, is first author on the new study.
The National Science Foundation supported the work through the Center for Aerosol Impacts on Climate and the Environment.
Timothy Bertram | EurekAlert!
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy