The forest cover of Northern Europe has been steadily expanding during the last 120 years. More terrestrial vegetation and carbon fixation leads to more export to surface waters. This may cause freshwater browning, as more degraded plant-litter end up as chromophoric (coloured) dissolved organic matter. Although most freshwater ultimately drains to coastal waters, the link between freshwater browning and coastal water darkening is poorly understood. Here, we explore this relationship through a combination of centennial records of forest and coastal water clarity, contemporary optical measurements in lakes and coastal waters, as well as an ocean drift model. We suggest a link between forest cover in Northern Europe and coastal water clarity in the Baltic, Kattegat and Skagerrak Sea and suggest that brown coloured freshwater from Northern European catchments dictates coastal water clarity across thousands of kilometres, from the Baltic lakes to the Barents Sea

Primary Presenter: Anders Frugaard Opdal, University of Bergen (anders.opdal@uib.no)

Authors:

Anders Frugård Opdal, University of Bergen  (anders.opdal@uib.no)

Tom Andersen, University of Oslo  (tom.andersen@ibv.uio.no)

Dag Olav Hessen, University of Oslo  (d.o.hessen@ibv.uio.no)

Christian Lindemann, University of Bergen  (chris.lindemann@uib.no)

Dag Aksnes, University of Bergen  (dag.aksnes@uib.no)