New research suggests melting glaciers are influencing not just sea level, but also the flow of organic carbon into the ocean.
The findings could help researchers gain insight into the global carbon cycle as the climate changes, the U.S. Geological Survey reported.
"This research makes it clear that glaciers represent a substantial reservoir of organic carbon," said Eran Hood, the lead author on the paper and a scientist with the University of Alaska Southeast (Juneau). "As a result, the loss of glacier mass worldwide, along with the corresponding release of carbon, will affect high-latitude marine ecosystems, particularly those surrounding the major ice sheets that now receive fairly limited land-to-ocean fluxes of organic carbon."
Polar ice sheets and mountain glaciers contain about 70 percent of the Earth's freshwater and stores and releases organic carbon to downstream environments as they melt. This phenomenon can change the productivity of aquatic ecosystems.
"This research demonstrates that the impacts of glacier change reach beyond sea level rise," said U.S. Geological Survey research glaciologist and co-author of the research Shad O'Neel. "Changes in organic carbon release from glaciers have implications for aquatic ecosystems because this material is readily consumed by microbes at the bottom of the food chain."
In the future glacier ice mass loss is starting to accelerate, potentially leading to an overall loss of nearly 17 million tons of glacial dissolved organic carbon by 2050, which is equivalent to about half the annual flux of dissolved water in the Amazon river.
The researchers noted these findings are the first of their kind, so therefore they have a high rate of uncertainty.
The work was supported by the National Science Foundation, the USGS Alaska Science Center and the DOI Alaska Climate Science Center. The Alaska Climate Science Center provides scientific information to help natural resource managers and policy makers respond effectively to climate change. The study was published in the Jan. 19 issue of Nature Geoscience.
