An earlier unknown important source of carbon just found in the Arctic has researchers puzzled over a previously neglected factor to local coastal ecosystems and worried about what it might suggest in a period of climate change.
In research published today, March 20th, on the journal Nature communications, aquatic chemists and hydrologists from The University of Texas at Austin’s Marine Science Institute and Jackson School of Geosciences, U.S. Fish and Wildlife Service and Florida State University, showcase proof of crucial, undetected densities and fluxes of dissolved organic matter appearing in the Arctic coastal waters, with the source being underwater flow on top on the frozen permafrost.
This water travels from land to sea undetected, but scientists now believe it features crucial amounts of carbon and other nutrients to Arctic coastal webs.
Previously Undetected Source of Carbon
Groundwater is known to be significant for carrying carbon and other types of nutrients to oceans, but in the Arctic, where a massive amount of water remains caught in frozen soil, its role has been unknown.
Researchers were puzzled to see that groundwater may be carrying a quantity of dissolved organic matter to the Alaskan Beaufort Sea that is almost equal to what comes from near rivers during summertime.
“We have to start thinking differently about groundwater,” said senior author Jim McClelland, professor of marine sciences at UT Austin. “The water that flows from rivers to the Arctic Ocean is pretty well accounted for, but until now, the groundwater flowing to this ocean hasn’t been.”
Scientists have generally presumed that groundwater entries from land to sea are small in the Arctic due to the fact that the constantly frozen ground, or permafrost, halts the flow of water below the surface.
However, the new study depicts sampling the concentration and age of the dissolved carbon and nitrogen in the groundwater moving underneath the surface at regions in northern Alaska, collects new and young organic carbon and nitrogen, as foreseen.
The researchers also found out that as groundwater moves towards the ocean, it combines with sheets of deeper soil and melting permafrost, gathering and transporting ancient carbon and nitrogen dating back to a few centuries to a millennium.
The Carbon is Probably a Millennia Old
The authors of the new paper determined that the supply of drainable organic carbon from groundwater equals as much as 70 percent of the dissolved organic matter stream from rivers to the Alaska Beaufort Sea during summertime.
“Despite its ancient age, dissolved organic carbon in groundwater provides a new and potentially important source of fuel and energy for local coastal food webs each summer,” said lead author Craig Connolly, a recent graduate of UT Austin’s Marine Science Institute. “The role that groundwater inputs play in carbon and nutrient cycling in Arctic coastal ecosystems, now and in the future as climate changes and permafrost continues to thaw, is something we hope will spark research interest for years to come.”
Co-author of the study, M. Bayani Cardenas, a professor in the Jackson School of Geosciences, said that climate change’s huge impact on the Arctic makes groundwater research incredibly important now.
“The Arctic is heating up twice as much as the rest of the planet. With that comes permafrost thawing and the birth of aquifers,” he said. “It is likely that groundwater transport in the Arctic will be more and more important in the future.”