A new factor which determines some of the properties of clouds that aid moderate Earth’s temperature could be decided in the oceans. They are home to phytoplankton, which when it decays produces molecules that turn airborne, if the molecules are not eaten by bacteria first.
A team of scientists led by researchers at UC San Diego discovered that the process trough y which marine bacteria eats phytoplankton has a direct role in modifying cloud properties. The bacteria break down phytoplankton into component molecules like lipids and fats. The molecules the bacteria leave uneaten then become airborne over the ocean’s surface. Once released in the atmosphere, the organic-enriched sea particles mix with dust and other particles, or even aerosol gases, in becoming the base for drops of moisture which ultimately forms clouds.
This finding, announced in the journal ACS Central Science, comes almost one year after scientists created a replica ocean at the Scripps Institution of Oceanography, UC San Diego, to see in a controlled frame the types of ocean particles that are contributing to cloud formation and if they cause human health issues when they become airborne. Because clouds and precipitation are two major variables which change the climate, the aerosol research has gained increasing importance in recent decades. Knowing the dynamics of clouds is essential for climate simulations that target to replicate atmospheric phenomena.
“It is exciting to finally be able to find a connection between microbes in seawater and atmospheric sea spray. These chemical changes ultimately affect the reflectivity of marine clouds and thus could have profound impacts on climate over a large portion of the planet,” said Kimberly Prather, a distinguished chair in atmospheric chemistry with appointments at Scripps and the Department of Chemistry and Biochemistry at UC San Diego.
The research gained its data from the National Science Foundation-funded study into Marine Particle Chemistry and Transfer Science (IMPACTS) carried out at Scripps’s Hydraulics Lab in the summer of 2014. Prather, who is the leader of UC San Diego’s Center for Aerosol Impacts on Climate and the Environment (CAICE), and his fellow researchers started with the observation that when bacteria breaks down plankton, they can release a lot of different insoluble fat-like molecules which later get caught by aerosol when waves break, a process that produces sea spray. These chemicals are a vast range of molecules such as proteins, sugars and fats.
Image Source: How It Works Daily