Nearly 1,000 new species of bacteria in snow and ice samples from Tibetan glaciers have been found by scientists, raising concerns about the spread of diseases as ice caps melt from global warming.
Researchers assessed whether bacteria species trapped in Tibet’s glaciers could make their way to 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 analyse what was left behind.
They found 968 unique bacteria species, of which 98 per cent were previously unknown to science.
The new findings come nearly a year after scientists found ancient glacier-entrapped viruses – some of which were over 15,000 years old – on the Tibetan plateau.
Ice sheets and glaciers make up nearly a tenth of the Earth’s surface cover, and a growing number of studies have also shown that they are melting due to the climate crisis.
Scientists suspect some of the trapped bacteria could be infectious to modern plants, animals and humans who particularly lack immunity to these older microbes.
“These microorganisms may carry novel virulence factors that make plants, animals, and humans vulnerable,” scientists wrote in the study.
Researchers caution that such modern and ancient pathogenic microbes 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 – one where melting snow and ice feeds several rivers that lead to densely populated parts across China and India.
“The Tibetan Plateau, which is known as the water tower of Asia, is the source of several of the world’s largest rivers, including the Yangtze, the Yellow River, the Ganges River and Yarlung Tsangpo (Brahmaputra River),” researchers wrote.
“The release of potentially hazardous bacteria could affect the two most populated countries in the world: China and India,” they added.
In future studies, scientists hope to assess if the microbes released from melting glaciers into rivers across the world pose a threat to downstream plants and animals.