More heart breaking news from the slow motion train wreck that is climate change. A new study finds that melting glaciers are dumping massive amounts of carbon into the worlds oceans with the potential to cause the oceans ecosystems to collapse.
"That’s the focus of a new paper by a research team that includes Florida State University assistant professor Robert Spencer. The study, published in Nature Geoscience, is the first global estimate by scientists at what happens when major ice sheets break down."
The organic carbon could be a temporary boon for tiny creatures at the bottom of the aquatic food chain that gobble the compound as food, but if this manna disappears because the glaciers have vanished, the overfed ocean ecosystems may collapse, the study authors warned.
"It could change the whole food web. We do not know how different ecological systems will react to a new influx of carbon," study co-author Robert Spencer, an assistant professor of oceanography at Florida State University, said in a statement.
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Eran Hood, lead study author, and his colleagues estimated how much organic carbon is trapped in the world's glaciers and ice sheets, and how much will be released into the sea if melting continues its rapid pace. The supply of organic carbon in the world's waterways will increase by 50 percent in the next 35 years, according to the study, which was published Monday (Jan. 19) in the journal Nature Geoscience. That's about half the amount of organic carbon spilled into the sea each year by the Mississippi River, the researchers said.
"This research makes it clear that glaciers represent a substantial reservoir of organic carbon," said Hood, a scientist at the University of Alaska Southeast. "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," he said. These high-latitude ecosystems are now receiving fairly limited inputs of organic carbon from land, Hood said in the statement.
From the abstract of the study published in
Nature Geoscience.
Polar ice sheets and mountain glaciers, which cover roughly 11% of the Earth's land surface, store organic carbon from local and distant sources and then release it to downstream environments. Climate-driven changes to glacier runoff are expected to be larger than climate impacts on other components of the hydrological cycle, and may represent an important flux of organic carbon. A compilation of published data on dissolved organic carbon from glaciers across five continents reveals that mountain and polar glaciers represent a quantitatively important store of organic carbon. The Antarctic Ice Sheet is the repository of most of the roughly 6 petagrams (Pg) of organic carbon stored in glacier ice, but the annual release of glacier organic carbon is dominated by mountain glaciers in the case of dissolved organic carbon and the Greenland Ice Sheet in the case of particulate organic carbon. Climate change contributes to these fluxes: approximately 13% of the annual flux of glacier dissolved organic carbon is a result of glacier mass loss. These losses are expected to accelerate, leading to a cumulative loss of roughly 15 teragrams (Tg) of glacial dissolved organic carbon by 2050 due to climate change — equivalent to about half of the annual flux of dissolved organic carbon from the Amazon River. Thus, glaciers constitute a key link between terrestrial and aquatic carbon fluxes, and will be of increasing importance in land-to-ocean fluxes of organic carbon in glacierized regions.