Review of 'Parameterization of the spectral light absorption coefficient of phytoplankton in the Baltic Sea: general, monthly and two component variants of approximation formulas' by Justina Meler

Abstract. This study presents three alternative models for estimation of absorption properties of Chromophoric Dissolved Organic Matter, aCDOM(l). For this analysis we used a database containing 556 absorption spectra measured in 2006–2009 in different regions of the Baltic Sea (open and coastal waters, the Gulf of Gdańsk and the Pomeranian Bay), at river mouths, in the Szczecin Lagoon and also in three Pomeranian lakes in Poland – Lakes Obłęskie, Łebsko and Chotkowskie. Observed variability range of the CDOM absorption coefficient at 400 nm, aCDOM(400), contained within 0.15–8.85 m−1. The variability in aCDOM(l) was parameterized with respect to three orders of magnitude variability in the chlorophyll a concentration Chla (0.7–119 mg m−3). Chlorophyll a concentration and CDOM absorption coefficient, aCDOM(400) were correlated, and statistically significant, non-linear empirical relationship between those parameters was derived (R2 = 0.83). Based on observed co-variance between these parameters, we derived two empirical mathematical models that enabled to project the CDOM absorption coefficient dynamics in natural waters and reconstruct the completed CDOM absorption spectrum in the UV and visible spectral domains. The first model used the chlorophyll a concentration as the input variable. The second model used the aCDOM(400), as the input variable. Both models were fitted to power function and the second order polynomial function was used as the exponent. Regression coefficients for derived formulas were determined for wavelengths from 240 to 700 nm at 5 nm intervals . Both approximation reflected the real shape of the absorption spectra with low uncertainty. Comparison of these approximation with other models of light absorption by CDOM proved that proposed parameterizations were better (bias from −1.45 % to 62 %, RSME from 22 % to 220 %) for estimation CDOM absorption in optically complex waters of the Baltic Sea and lakes.

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Parameterization of the spectral light absorption coefficient of phytoplankton in the Baltic Sea: general, monthly and two-component variants of approximation formulas

10.5194/os-2018-69 ◽

2018 ◽

Cited By ~ 1

Author(s):

Justyna Meler ◽

Sławomir B. Woźniak ◽

Joanna Stoń-Egiert ◽

Bogdan Woźniak

Keyword(s):

Baltic Sea ◽

Chlorophyll A ◽

Light Absorption ◽

Wide Range ◽

Two Component ◽

Approximation Formulas ◽

Accessory Pigment ◽

Classic Form ◽

The One ◽

The Baltic

Abstract. The paper presents approximate formulas for parameterizing the coefficient of light absorption by phytoplankton aph(λ) in Baltic Sea surface waters. Over a thousand absorption spectra (in the 350–750 nm range), recorded during nine years of research carried out in different months of the year and in various regions of the southern and central Baltic, were used to derive these parameterizations. The analysed empirical material was characterized by a wide range of variability: the total chlorophyll a concentration (Tchla) varied between 0.3 and > 140 mg m−3, the ratio of the sum of all accessory pigment concentrations to chlorophyll a (ΣCi / Tchla) varied between 0.21 and 1.5, and the absorption coefficients aph(λ) at individual light wavelengths varied over almost three orders of magnitude. Different versions of the parameterization formulas were derived on the basis of the data gathered: a one-component parameterization in the classic form of a power function with Tchla as the only variable, and a two-component formula – the product of the power and exponential functions, with Tchla and ΣCi / Tchla as variables. There were distinct differences between the general version of the one-component parameterization and its variants developed for individual months of the year. In contrast to the general parameterization, both the monthly and the two-component variants enable, at least partially, the variability of pigment composition occurring throughout the year in the Baltic phytoplankton populations examined here to be taken into account.

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Parameterization of the light absorption properties of chromophoric dissolved organic matter in the Baltic Sea and Pomeranian lakes

Ocean Science ◽

10.5194/os-12-1013-2016 ◽

2016 ◽

Vol 12 (4) ◽

pp. 1013-1032 ◽

Cited By ~ 12

Author(s):

Justyna Meler ◽

Piotr Kowalczuk ◽

Mirosława Ostrowska ◽

Dariusz Ficek ◽

Monika Zabłocka ◽

...

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Absorption Coefficient ◽

Baltic Sea ◽

Chlorophyll A ◽

Chromophoric Dissolved Organic Matter ◽

The Baltic Sea ◽

Absorption Properties ◽

Chlorophyll A Concentration ◽

The Baltic

Abstract. This study presents three alternative models for estimating the absorption properties of chromophoric dissolved organic matter aCDOM(λ). For this analysis we used a database containing 556 absorption spectra measured in 2006–2009 in different regions of the Baltic Sea (open and coastal waters, the Gulf of Gdańsk and the Pomeranian Bay), at river mouths, in the Szczecin Lagoon and also in three lakes in Pomerania (Poland) – Obłęskie, Łebsko and Chotkowskie. The variability range of the chromophoric dissolved organic matter (CDOM) absorption coefficient at 400 nm, aCDOM(400), lay within 0.15–8.85 m−1. The variability in aCDOM(λ) was parameterized with respect to the variability over 3 orders of magnitude in the chlorophyll a concentration Chl a (0.7–119 mg m−3). The chlorophyll a concentration and aCDOM(400) were correlated, and a statistically significant, nonlinear empirical relationship between these parameters was derived (R2 =  0.83). On the basis of the covariance between these parameters, we derived two empirical mathematical models that enabled us to design the CDOM absorption coefficient dynamics in natural waters and reconstruct the complete CDOM absorption spectrum in the UV and visible spectral domains. The input variable in the first model was the chlorophyll a concentration, and in the second one it was aCDOM(400). Both models were fitted to a power function, and a second-order polynomial function was used as the exponent. Regression coefficients for these formulas were determined for wavelengths from 240 to 700 nm at 5 nm intervals. Both approximations reflected the real shape of the absorption spectra with a low level of uncertainty. Comparison of these approximations with other models of light absorption by CDOM demonstrated that our parameterizations were superior (bias from −1.45 to 62 %, RSME from 22 to 220 %) for estimating CDOM absorption in the optically complex waters of the Baltic Sea and Pomeranian lakes.

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Parameterization of phytoplankton spectral absorption coefficients in the Baltic Sea: general, monthly and two-component variants of approximation formulas

Ocean Science ◽

10.5194/os-14-1523-2018 ◽

2018 ◽

Vol 14 (6) ◽

pp. 1523-1545 ◽

Cited By ~ 2

Author(s):

Justyna Meler ◽

Sławomir B. Woźniak ◽

Joanna Stoń-Egiert ◽

Bogdan Woźniak

Keyword(s):

Baltic Sea ◽

Chlorophyll A ◽

Absorption Coefficients ◽

Wide Range ◽

Two Component ◽

Approximation Formulas ◽

Accessory Pigment ◽

Classic Form ◽

The One ◽

The Baltic

Abstract. This paper presents approximate formulas (empirical equations) for parameterizing the coefficient of light absorption by phytoplankton aph(λ) in Baltic Sea surface waters. Over a thousand absorption spectra (in the 350–750 nm range), recorded during 9 years of research carried out in different months of the year and in various regions of the southern and central Baltic, were used to derive these parameterizations. The empirical material was characterized by a wide range of variability: the total chlorophyll a concentration (Tchl a) varied between 0.31 and 142 mg m−3, the ratio of the sum of all accessory pigment concentrations to chlorophyll a (∑Ci/Tchla) ranged between 0.21 and 1.5, and the absorption coefficients aph(λ) at individual light wavelengths varied over almost 3 orders of magnitude. Different versions of the parameterization formulas were derived on the basis of these data: a one-component parameterization in the “classic” form of a power function with Tchl a as the only variable and a two-component formula – the product of the power and exponential functions – with Tchl a and ∑Ci/Tchla as variables. We found distinct differences between the general version of the one-component parameterization and its variants derived for individual months of the year. In contrast to the general variant of parameterization, the new two-component variant takes account of the variability of pigment composition occurring throughout the year in Baltic phytoplankton populations.

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Modeling the growth rates of cyanobacteria and diatoms in the Baltic Sea

10.5194/egusphere-egu2020-3372 ◽

2020 ◽

Author(s):

Malgorzata Stramska ◽

Joanna Stoń-Egiert ◽

Miroslawa Ostrowska ◽

Jaromir Jakacki

Keyword(s):

Baltic Sea ◽

Growth Rates ◽

Environmental Conditions ◽

Light Absorption ◽

The Baltic Sea ◽

Absorption Properties ◽

Water Turbidity ◽

Order Of Magnitude ◽

Phytoplankton Absorption ◽

The Baltic

Potential influences of various environmental factors on phytoplankton growth rates in the Baltic Sea are discussed. Our focus is on quantitative comparisons of growth rates of two phytoplankton functional types, diatoms and cyanobacteria. Growth rates are calculated as a function of quanta absorbed by phytoplankton. This in turn depends on phytoplankton exposition to light, which was simulated to represent realistic conditions encountered in the Baltic Sea in summer. In addition, phytoplankton absorption capability was characterized by absorption coefficients derived from measurements on phytoplankton mono-cultures isolated from the Baltic Sea. Estimated exposition of phytoplankton to photosynthetically available radiation (PAR) in surface waters can change about five times in case of the same solar surface insolation and water turbidity, solely due to changes in the mixed layer depth from 2 to 20 meters. When additionally changes in water turbidity are considered, phytoplankton PAR exposition can change by one order of magnitude. Light exposition and absorption properties of phytoplankton determine the effectiveness of light absorption. In our simulations for the same species of phytoplankton, changes in light exposition resulted in differences of an order of magnitude of absorbed quanta. The importance of accounting for absorptive properties is underlined through comparisons of the number of quanta absorbed by different phytoplankton types in the same environmental conditions. The effectiveness of light absorption translates to different growth rates achieved by each phytoplankton type. Our results support the notion that knowledge about phytoplankton absorption properties and light exposition is crucial when modeling phytoplankton in the Baltic Sea. Further progress is currently hindered by a lack of systematic information about maximum phytoplankton growth rates and their responses to specific environmental conditions for different functional types. Such information should be inferred in the future in specially designed laboratory experiments, that encompass realistic ranges of phytoplankton exposition to light, nutrients, temperatures and other conditions. This work has been funded by the National Science Centre (contract number: 2017/25/B/ST10/00159 entitled: &#8220;Numerical simulations of biological-physical interactions and phytoplankton cycles in the Baltic Sea&#8221;) and by the statutory funds of IOPAN.

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Optical model for the Baltic Sea with an explicit CDOM state variable: a case study with Model ERGOM (version 1.2)

Geoscientific Model Development ◽

10.5194/gmd-14-5049-2021 ◽

2021 ◽

Vol 14 (8) ◽

pp. 5049-5062

Author(s):

Thomas Neumann ◽

Sampsa Koponen ◽

Jenni Attila ◽

Carsten Brockmann ◽

Kari Kallio ◽

...

Keyword(s):

Baltic Sea ◽

Light Absorption ◽

Model Performance ◽

Ecosystem Model ◽

The Baltic Sea ◽

State Variable ◽

Biogeochemical Models ◽

Changing Patterns ◽

The Baltic ◽

New Generation

Abstract. Colored dissolved organic matter (CDOM) in marine environments impacts primary production due to its absorption effect on the photosynthetically active radiation. In coastal seas, CDOM originates from terrestrial sources predominantly and causes spatial and temporal changing patterns of light absorption which should be considered in marine biogeochemical models. We propose a model approach in which Earth Observation (EO) products are used to define boundary conditions of CDOM concentrations in an ecosystem model of the Baltic Sea. CDOM concentrations in riverine water derived from EO products serve as forcing for the ecosystem model. For this reason, we introduced an explicit CDOM state variable in the model. We show that the light absorption by CDOM in the model can be improved considerably in comparison to approaches where CDOM is estimated from salinity. The model performance increases especially with respect to spatial CDOM patterns due to the consideration of single river properties. A prerequisite is high-quality CDOM data with sufficiently high spatial resolution which can be provided by the new generation of ESA satellite sensor systems (Sentinel 2 MSI and Sentinel 3 OLCI). Such data are essential, especially when local differences in riverine CDOM concentrations exist.

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Radiation model for the Baltic Sea with an explicit CDOM state variable: a case study with Model ERGOM (version 1.2)

10.5194/gmd-2020-318 ◽

2020 ◽

Author(s):

Thomas Neumann ◽

Sampsa Koponen ◽

Jenni Attila ◽

Carsten Brockmann ◽

Kari Kallio ◽

...

Keyword(s):

Baltic Sea ◽

Light Absorption ◽

Ecosystem Model ◽

The Baltic Sea ◽

State Variable ◽

Biogeochemical Models ◽

Changing Patterns ◽

The Baltic ◽

Traditional Approaches ◽

New Generation

Abstract. Colored dissolved organic matter (CDOM) in marine environments impacts primary production due to its absorption effect on the photosynthetically active radiation. In coastal seas, CDOM originates from terrestrial sources predominantly and causes spatial and temporal changing patterns of light absorption which should be considered in marine biogeochemical models. We propose a model approach in which Earth Observation (EO) products are used to define boundary conditions of CDOM concentrations in an ecosystem model of the Baltic Sea. CDOM concentrations in riverine water derived from EO products serve as forcing for the ecosystem model. For this reason, we introduced an explicit CDOM state variable in the model. We show that the light absorption by CDOM in the model can be improved considerably compared to traditional approaches where, e.g., CDOM is estimated from salinity. A prerequisite is high quality CDOM data with sufficiently high spatial resolution which can be provided by the new generation of ESA satellite sensor systems (Sentinel 2 MSI and Sentinel 3 OLCI).

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Temporal and spatial sedimentation rate variabilities in the eastern Gotland Basin, the Baltic Sea

Boreas ◽

10.1080/03009480210645 ◽

2002 ◽

Vol 31 (1) ◽

pp. 65-74 ◽

Cited By ~ 12

Author(s):

Christian Christiansen ◽

Helmar Kunzendorf ◽

Kay-Christian Emeis ◽

Rudolf Endler ◽

Ulrich Struck ◽

...

Keyword(s):

Baltic Sea ◽

Sedimentation Rate ◽

The Baltic Sea ◽

Gotland Basin ◽

Temporal And Spatial ◽

The Baltic

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Russian Oil: Production and Exports

Voprosy Ekonomiki ◽

10.32609/0042-8736-2003-9-136-146 ◽

2003 ◽

pp. 136-146

Author(s):

K. Liuhto

Keyword(s):

Baltic Sea ◽

Statistical Data ◽

Oil Production ◽

The Baltic Sea ◽

North West ◽

The North ◽

Oil Transportation ◽

Sea Ports ◽

The Baltic

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.

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