The researchers assessed whether bacterial species trapped in Tibetan glaciers could reach other regions as snow and ice melt, said the new study, published last week in the journal Nature Biotechnology. Ice samples from 21 glaciers in Tibet were collected between 2010 and 2016 by researchers – including those from the Chinese Academy of Sciences – who melted them to analyze what was left behind. They found 968 unique species of bacteria, of which 98 percent were previously unknown to science. The new findings come nearly a year after scientists discovered ancient viruses trapped in glaciers – some of which were more than 15,000 years old – on the Tibetan Plateau. Ice sheets and glaciers make up nearly a tenth of Earth’s surface coverage, and a growing number of studies have also shown that they are melting due to the climate crisis. Scientists suspect that some of the trapped bacteria could be infectious to modern plants, animals and humans that are not particularly immune to these older microbes. “These microorganisms may carry new pathogens that make plants, animals and humans vulnerable,” the scientists wrote in the study. The researchers warn that such modern and ancient pathogens trapped in glaciers “could lead to local epidemics and even pandemics”. The newly discovered bacteria in the current study also come from a particularly important region of the world—a region where melting snow and ice feeds many rivers that lead to densely populated places across China and India. “The Tibetan Plateau, which is known as the water tower of Asia, is the source of many of the world’s major rivers, including the Yangtze, the Yellow River, the Ganges River and the Yarlung Tsangpo (Brahmaputra River),” wrote the researchers. “The release of potentially dangerous bacteria could affect the two most populous countries in the world: China and India,” they added. In future studies, scientists hope to assess whether microbes released by melting glaciers into rivers around the world pose a threat to downstream plants and animals.
