Researchers have shown for the first time how Arctic rivers are transporting vast quantities of organic carbon into the oceans. This process occurs as the permafrost melts, which is due to climate change.
Despite the massive impact of climate change on the world's Arctic
regions, there is a scarcity of data on exactly how the Arctic regions
are changing. In particular, there is little understanding of how
thawing permafrost is impacting the global carbon cycle.
The EU-funded 'Terrestrial organic matter characterization in Arctic River through molecular and isotopic analyses' (TOMCAR-PERMAFROST
) project is studying the Great Whale River in Canada to understand the effects of thawing permafrost.
Researchers used geographic information systems and biochemical
analysis to reveal how much carbon is transferred into the oceans by
Arctic rivers. They are particularly interested in organic matter, as
this has a huge effect on carbon cycles.
The project team found that the Great Whale River transported
between 200 and 700 tonnes of dissolved organic carbon (DOC) per day
during the spring flooding season. This is both old and new DOC, and the
composition is influenced by whether there is fresh snow cover in the
TOMCAR-PERMAFROST also noted that mercury concentration in the River
increased dramatically during the flood period. During the project,
scientists recorded the highest-ever concentration of mercury in an
The findings of this project are alarming, because such large
influxes of DOC into the world's oceans will intensify the effects of
global warming. However, the information is valuable to researchers
trying to model the long-term effects of climate change.