Organic carbon budget for the Gulf of Bothnia

The potential of using remote sensing data to estimate air–sea CO<sub>2</sub> exchange in the Baltic Sea

“…The GB is a sink in 2009 in our study, but this value decreases from 1998 to 2009. This flux has a value of 0.5 mmol m −2 yr −1 in 2002, lower than the value of 2.9 mol m −2 yr −1 from Algesten et al (2006). This estimation is based on a few days of measurements from a few stations in the GB.…”

“…Most previous research results concerning the carbon budget of the Baltic Sea cover shorter periods, indicating a range between −1.16 and 2.9 mol m −2 yr −1 )(e.g. Wesslander et al, 2010;Kulinski and Pempkowiak, 2012), though the maximum values reported in these studies are all found in the same one or two years (Algesten et al, 2006). Half of the studies demonstrate that the Baltic Sea or certain basins of it act as sources, while the other studies demonstrate that the Baltic Sea acts as a sink for the atmosphere (Norman et al, 2013a).…”

The carbon budget of the Baltic Sea

“…The aim was to develop a state-of-the-art carbon budget for the entire Baltic Sea that would provide a comprehensive description of the boundary carbon fluxes. Based on both experimental and literature data (Pempkowiak and Kupryszewski, 1980;Granskog et al, 2005;Thomas et al, 2005Thomas et al, , 2010Algesten et al, 2006;Kuliński and Pempkowiak, 2008;Dzierzbicka-Głowacka et al, 2010;Kowalczuk et al, 2010), major carbon fluxes were selected for the present investigation. They include carbon exchange between the Baltic and the North Sea, river input, organic carbon burial in bottom sediments, atmospheric deposition, point sources (all terrestrial carbon loads other than those entering the Baltic Sea from rivers), fisheries, and net CO 2 exchange between sea water and the atmosphere (Fig.…”

“…2). Since the net CO 2 exchange is temporally and spatially highly variable, and the results reported in the literature are ambiguous (Thomas and Schneider, 1999;Algesten et al, 2006;Kuss et al, 2006;Wesslander et al, 2010), it was calculated using the mass balance approach. The mass balance is based on the assumption that a steady state occurs, as a result of which all carbon sinks and sources in the Baltic Sea balance one another.…”

Environmental Impacts—Marine Biogeochemistry

“…In the northern boreal regions, where phytoplankton primary production is low, organic matter input from terrestrial sources becomes increasingly important for the marine C fluxes. Food web models (Sandberg et al 2004;Sandberg 2007) and CO 2 budgets have shown Bothnian Bay, the northernmost Baltic sub-basin, to be a net heterotrophic system (Algesten et al 2004(Algesten et al , 2006, whereas the Bothnian Sea oscillates between net autotrophy and heterotrophy (Algesten et al 2004). In contrast, a CO 2 air-sea flux balance (Löffler et al 2012) indicated that on average the Bothnian Sea acts as a sink for atmospheric CO 2 and must thus be considered as a net autotrophic system.…”