Hundreds of thousands of tons of bacteria are being released annually into the air through melting glaciers in the northern latitudes, a study in the Communications Earth & Environment reported. Glaciers melting because of global warming could cause a release of 650,000 tons of carbon a year for the next 80 years in the northern hemisphere.
Scientists from the journal collected data from eight glaciers across Europe and North America and found that tens of thousands of microbes are in each milliliter of water. This data helped the researchers to estimate that the bacteria being swept through streams and water would be 650,000 tons of carbon a year.
“We are seeing the glaciers die before our eyes, affecting the microbes that are there, with implications for us locally and globally,” Dr. Arwyn Edwards, a member of the study team told The Guardian. “The mass of microbes released is vast even with moderate warming.”
Edwards said the researchers don’t have enough data to determine the threat of the organisms, but they will continue conducting data to assess the risk of each microbe.
According to UNESCO, the U.N. cultural agency, nearly a third of glaciers are predicted to disappear by 2050. These glaciers include Tanzania’s Mount Kilimanjaro, Yellowstone’s Yosemite, and Italy’s Dolomites. The cause of the disappearances is linked to rising temperatures caused by global warming.
The loss of these glaciers will majorly impact the landscape of these areas, often focal points for tourists. To combat the losses, UNESCO says that policies should be made surrounding these glaciers to help reduce natural disasters and risks caused by their disappearances. According to Tales Carvalho, lead author of the report, “As glacier lakes fill up, they can burst and can cause catastrophic floods downstream.”
Each year, around 58 billion tons of ice melt off the glaciers and cause sea levels to rise. Carvalho says the best way to save the glaciers would be to lessen carbon emissions.
Across 50 of its World Heritage sites, UNESCO monitors 18,600 glaciers. Out of these sites, a third of them are set to disappear. However, the remaining glaciers can be saved if temperatures stay controlled.
Advances in satellite technology have revealed that the world’s glaciers contain significantly less ice than previously thought, according to a study published in Nature Geoscience on Monday.
The Nature Geoscience study assessed how quickly glaciers were moving across the landscape, or their velocity. These measurements allow scientists to more accurately measure volume, but collecting this information has been limited by technology.
The work analyzed more than 800,000 pairs of images of glaciers taken between 2017 and 2018, and found that many were shallower than previously assessed. Scientists now estimate there is 20 percent less glacial ice present with the potential to melt into the ocean and raise sea levels.
The revised estimate reduces global sea level rise by 3 inches if all glaciers were to melt. This raises concern for some communities that rely on seasonal melt from glaciers to feed rivers and irrigate crops. If glaciers contain less ice, water will run out sooner than expected. Between 2000 and 2019, these rivers of ice lost roughly 5.4 trillion tons.
Countries are already struggling with disappearing glaciers. Peru is investing in desalination to make up for declining freshwater, and Chile hopes to create artificial glaciers in its mountains.
Iowa State University’s Neal Iverson and a team of researchers are working on research that will predict how much glaciers will contribute to the rise of sea levels.
The research will focus on the extent to which glacier-flow to oceans is likely speed up over the next century as the climate warms.
Iverson, an Iowa State University professor of geological and atmospheric sciences who has studied glaciers in Iceland and Norway, and the rest of the research team will look to lab experiments and field work to build more realistic computer models of glacier flow.
Iverson said about the project:
“Glaciologists are trying to predict how fast glaciers will flow to the oceans. To do that, we need new lab and field data to include complexity in models that is usually neglected. These are complicated systems. Modeling them is hard. But we need to include how water in ice affects its flow resistance, and we need sliding laws that are based on the real topography of glacier beds and that include rock friction. Adding these things really matters.”
Two new grants will help Iverson and his team fund their research, both of which grants are from the National Science Foundation. The research will also receive funding from the United Kingdom’s Natural Environment Research Council to support the work of applied mathematicians at the University of Oxford in England.
Iverson is the lead investigator on both grant proposals. The other researchers are Lucas Zoet, an assistant professor at the University of Wisconsin-Madison and a former postdoctoral research associate at Iowa State; Ian Hewitt, an associate professor and university lecturer at Oxford’s Mathematical Institute; and Richard Katz, a professor of geodynamics at Oxford.
The first project will look at temperate ice, or ice at its melting point, and how this soft, watery ice resists deformation. That’s important because the resistance to deformation of temperate ice at the edges of ice streams – areas of rapid ice flow within the Antarctic ice sheet that can be hundreds of miles long and tens of miles wide – holds back the flowing ice.
The second project will support development of better “sliding laws” to help predict the sliding speeds of glaciers and ice sheets. Sliding laws are the mathematical relationships between the glacier sliding speed and the factors that control it, such as the stresses below the glacier, the water pressure there, the topography of the glacier bed and the concentration of debris in glacier ice.
The new projects will add complexity to Iverson’s lab experiments. Debris, for example, will be added to the ice ring to study friction between it and the rock bed during sliding. In other experiments, temperate ice will be sheared between rotating plates to study how its resistance to flow depends on its water content.