Arctic blue carbon: human and climatic drivers of change

Nature-based solutions to mitigate climate change include the drawdown and burial of carbon by natural systems. In terrestrial systems this function can be performed by forests and such buried carbon is called green carbon. In the marine environment, these carbon sequestering and storing systems are termed blue carbon stores and there is evidence that at high latitudes significant quantities of blue carbon are stored in systems including algal deposits and sediments. That carbon can be the product of glacially induced primary production [via upwelling of deeper water nutrients], but also, carbon directly produced by marine macrophytes. Arctic coastlines in particular are inundated with fjords, however, there is a paucity of information on their contributions to carbon burial through changing climates and anthropogenic inputs. Understanding how these drivers of fjordic carbon sequestration influenced previous rates of carbon burial will be key to predicting how these carbon storage systems will react to future climate and land use changes.

Historic climate change has been shown to alter carbon burial and evidence is now emerging that in mid-latitude fjord systems, human interactions with their environment can alter carbon burial through changes in land use and its impact on organic material exported to the surrounding fjords. In this context Greenland is of particular importance; it is at risk of warming-driven glacial melt and also, Nuuk [the largest populated area] has shown substantial recent population increases which are projected to increase further as warming continues. Together, projected warming and changing demography may change blue carbon burial in Greenlandic repositories over the coming century.


Aim: This project will quantify current and historic rates and mechanisms of carbon sequestration, burial and remineralisation at a range of Greenlandic fjord systems [including those generated by macrophytes, coralline algae and sediments] under representative climate and land use changes. These data will allow us to explore the future potential capacity of Greenland's fjords to act as efficient carbon sinks in a changing climate and with increasing anthropogenic demands.