Particulate organic carbon in the southern Baltic Sea: numerical simulations and experimental data

Abstract

The influx of solar radiation to the Baltic Sea and its penetration into its waters is described on the basis of selected results of optical and bio-optical studies in the Baltic published by various authors during the past ca 50 years. The variability in the natural irradiance of this sea is illustrated on time scales from short-term fluctuations occurring during a single day to differences in mean monthly values over a period of many years. Data on variability of the proportions between UV, * The paper was invited by the Chairman of the Polish National SCOR. The work was carried out within the framework of IO PAS's statutory research and also as part of the Satellite Monitoring of the Baltic Sea Environment project -SatBałtyk, co-founded by the European Union through European Regional Development Fund contract No. POIG 01.01.02-22-011/09.The complete text of the paper is available at http://www.iopan.gda.pl/oceanologia/ 534 J. Dera, B. Woźniak VIS and IR energy in the light reaching the sea surface are also discussed. Longterm monthly mean values of the incident solar radiation flux at the surface of the Baltic Proper are given; they were obtained from meteorological and solar radiation measurements and model approximations. The transmittances of these mean monthly radiation fluxes across the surface of the Baltic are given, as are the typical energy and spectral characteristics of the underwater irradiance, its attenuation with depth in the sea and the associated euphotic zone depths, as well as typical ranges of variability of these characteristics in different Baltic basins. Some of these characteristics are illustrated by typical empirical data. These mean values are not fully representative, however, because with the sole use of classical in situ measurement methods from on board research vessels in the Baltic, it has not been possible to gather a sufficiently representative set of empirical data that would adequately reflect the variability of the optical characteristics of all the basins of this sea. The article goes on to introduce the statistical model of vertical distributions of chlorophyll a concentration in the Baltic and the bio-optical model of Baltic Case 2 waters, the use of which contribute very significantly to this description of the optical characteristics and will enable this data set to be hugely expanded to include all the Baltic basins. This opportunity is presented by the optical parameterization of Baltic Case 2 waters, i.e. by the mathematical formulas of the model linking the coefficient of attenuation of downward irradiance with the surface chlorophyll a concentration, as well as the method developed for the efficient and systematic satellite remote sensing of the chlorophyll a concentration over the entire Baltic Sea area.

Carbon Cycling in the Baltic Sea

“…To a large extent, the cycle is controlled by phytoplankton activity (Dzierzbicka-Głowacka et al 2010;. To a large extent, the cycle is controlled by phytoplankton activity (Dzierzbicka-Głowacka et al 2010;.…”

Population modelling of <i>Acartia</i> spp. in a water column ecosystem model for the South-Eastern Baltic Sea

“…Results obtained by Dzierzbicka-Glowacka et al (2010) indicated that the 1-D POC model might be a useful tool for actual carbon cycle and pelagic variables investigations and prediction of theirs changes. Calibration of the model and comparison of model results with measurements for temperature and the phytoplankton biomass and nutrients concentration in 1995-2000 are given in a paper Dzierzbicka-Glowacka et al (2010). With respect to all the parameters, the correlations of the observed regularities decreased from the surface to the bottom.…”

“…The different sinks and sources for 1-D POC model are put together in Table 1 in Dzierzbicka-Glowacka et al (2010), while the mathematical formulation for biogeochemical processes in the model is presented in Appendix A-C in Dzierzbicka-Glowacka (2005b) and Dzierzbicka-Glowacka et al (2010). Results obtained by Dzierzbicka-Glowacka et al (2010) indicated that the 1-D POC model might be a useful tool for actual carbon cycle and pelagic variables investigations and prediction of theirs changes.…”

“…This ecosystem model supplemented with the population dynamics submodel for copepods and a component for pelagic detritus was used to study the dynamics of Pseudocalasus minutus elongatus in the Southern Baltic Sea (Dzierzbicka-Glowacka, 2005a,b). The 1-D CEM model reduced to a 1-D POC Particulate Organic Carbon Model with an equation for dead organic matter (pelagic detritus) is presented in Dzierzbicka-Glowacka et al (2010). The 1-D POC model is an ecosystem model able to simulate biogeochemical processes in the physical environment.…”

Distribution and origin of organic matter in the Baltic Sea sediments dated with 210Pb and 137Cs

“…Direct discharges of treated sewage are of importance due to the load of nutrients they carry. Increasing eutrophication also implies phytoplankton blooms, enhancing the "biological pump" phenomenon (Dzierzbicka-Głowacka et al, 2010).…”