It’s well known that the human gut is a thriving bacterial ecosystem—not to mention the skin, lungs, and various other parts of the body. But the breadth and depth of microbes’ participation in many systems on the planet are still not widely understood. For instance, there is evidence that there are microbes in the clouds, hitching thousand-mile rides through the atmosphere and helping to cause rain or snow along the way.
Some of these cloud microbes seem to come from the soil, but others are likely rising up out of the ocean, a riotous soup of bacteria and viruses. In a new study in Nature Communications, researchers used a 13,000-liter tank of seawater to observe what microbial species are in the water and which manage to become airborne in sea spray, thus launching themselves into the atmosphere.
The work was intended to help answer a long-standing question: Exactly how do microbes rising out of the ocean connect to the planet’s climate? Substances released from the ocean may help manage global temperature, according to Kim Prather, an atmospheric chemist at the University of California, San Diego, who has pioneered the study of microbes in the sky. “If you put out different types of spray, you could make clouds that are brighter and whiter to cool things down,” she says. “Depending on what comes out of the ocean, it could really change the temperature of the planet.”