Bacteria and fungi were discovered floating among storm clouds at a surprising 30,000 feet about the Earth's surface could be impacting climate, a team of U.S. scientists announced on Tuesday. The study's findings were published in the Proceedings of the National Academy of Sciences on Monday, the Los Angeles Times reported.
According to study coauthor Athanasios Nene, prior to this study, scientists typically studied airborne bacteria from the ground. However, during Nene and his colleagues' research, the team traveled on NASA aircraft to collect samples before, during and after hurricanes Earl and Karl in 2010, the LA Times reported. The report stated that the team's plane flew into the upper troposphere to collect samples.
The team conducted nine flights over the Caribbean and the Midwest Atlantic to collect their samples. The air samples, which were on average 212 cubic feet of ambient air, were run through a cycle of filters. According to the Times, the scientists honed in on a ribosomal RNA gene called SSU rRNA, which readily identifies bacteria.
The study revealed that bacteria accounted for 20 percent of the material scientists believed would be merely sea salt and dust. "We were surprised," Nenes told reporters. The filters also picked up fungi, the Times reported.
Researchers discovered 17 types of bacteria that were found in all the samples. This finding led the team to believe that the organisms are part of the core microbiome of the lower atmosphere.
According to the LA Times, in order to survive, the microbes must have developed the ability to bear freezing temperatures, feed on scarce food supplies and deal with ultraviolet radiation. Some microbes may even be able to freeze and collect water vapor and seed clouds, which could lead to rain.
The fact that the microbes not only lived, but also thrived, in the high altitudes is an important finding. Nenes said, "It definitely lends to the idea that life is pretty resilent and you can adapt to almost any environment in which bacteria can live on Earth-and whether they could do so on other planets as well."