Oceanologia No. 39 (1) / 97

Contents

Papers

• Jolanta Kusmierczyk-Michulec, Roman Marks, Krystyna Kruczalak: Modelling of the aerosol size distribution and aerosol optical properties over the Baltic Sea
• Slawomir B. Wozniak: Mathematical spectral model of solar irradiance reflectance and transmittance by a wind-ruffled sea surface. Part 2. Modelling results and application
• Jan Piechura, Waldemar Walczowski, Agnieszka Beszczynska-Möller: On the structure and dynamics of the water in the Slupsk Furrow
• Lidia Dzierzbicka-Glowacka, Andrzej Zielinski: Numerical studies of the influence of the nutrient regeneration mechanism on the chlorophyll a concentration in a stratified sea
• Grazyna Kowalewska, Joanna Konat: Distribution of polynuclear aromatic hydrocarbons (PAHs) in sediments of the southern Baltic Sea

Dissertations

• Jolanta Kusmierczyk-Michulec: An optical model of the atmosphere for satellite research of the Baltic Sea (review by J. Olszewski)
• Tymon Zielinski: Application of the lidar method to determine the influence of dynamic atmospheric conditions on the concentrations and particle size distribution functions of the marine aerosol (review by K. Korzeniewski)
• Ksenia Pazdro: Identification of fatty acids and their occurrence in the southern Baltic ecosystem (review by J. Pempkowiak)

Papers

Modelling of the aerosol size distribution and aerosol optical properties over the Baltic Sea
Oceanologia 1997, no. 39 (1), pp. 3–16

Keywords: Baltic Sea, Aerosol size distribution, Empirical orthogonal functions, Extinction coefficient, Single scattering albedo Manuscript received September 6, 1996, in final form January 9, 1997.

Abstract

Some applications of the method of modelling the aerosol size spectral distribution are presented. The single scattering albedo of the aerosol is calculated on the basis of particle counter measurements and the results of the empirical orthogonal functions method. The experimental measurements were done during two research cruises on the Baltic Sea and during two coastal experiments at Lubiatowo in 1994 and 1995. The results confirmed that the aerosol size distribution can be represented by a slowly varying background of dust-like particles superimposed on the distribution of marine particles, multiplied by amplitude functions reflecting the latter's contribution. The amplitude functions were found to be dependent on the speed and direction of the wind.

Mathematical spectral model of solar irradiance reflectance and transmittance by a wind-ruffled sea surface. Part 2. Modelling results and application
Oceanologia 1997, no. 39 (1), pp. 17–34

Keywords: Sea surface reflectance, Sea surface transmittance Manuscript received October 14, 1996, in final form December 20, 1996.

Abstract

This paper presents analyses of spectral dependences of solar irradiance reflectance and transmittance on a wide range of environmental factors. It is based on the theoretical model worked out earlier (Wozniak, 1996a), which includes relationships, modified by the author, for the sea surface slope distribution and foam coverage as functions of a dynamic factor, i.e. the mean height of the wind waves . The Snell and Fresnel laws are applied to light transmission through the surface. Spectral dependences of light refraction in the 350–18000 nm range are taken into account, but polarisation effects are neglected. On the basis of this model, a table of solar irradiance reflectances and transmittances has been computed for a surface illuminated by direct and diffuse light, for solar zenith angles from 1–85^o, and for various sea states and values of the irradiance diffuseness in the atmosphere. In addition, a simplified polynomial method for calculating the real surface reflectance and transmittance of solar irradiance is presented.

On the structure and dynamics of the water in the Slupsk Furrow
Oceanologia 1997, no. 39 (1), pp. 35–54

Keywords: Water transport, Mesoscale dynamics, Mixing Manuscript received November 14, 1996, in final form January 6, 1997.

Abstract

During 1994–1996 nearly 50 cruises both along and across the Slupsk Furrow were made with the use of an undulating CTD. Special attention was paid to the Slupsk Sill separating the Slupsk Furrow from the Bornholm Deep.

The flow of higher-salinity water over the Slupsk Sill was recorded; it was splash-like in nature. This finding was further confirmed by the temperature and salinity distribution of the deep water in the Slupsk Furrow. The origin, frequency and duration of this flow are not yet clear. The transport of waters flowing into the Slupsk Furrow is very often wave-like. Internal waves were detected, propagating both along the axis and across the channel. The break up of the internal waves and the resultant diapycnal mixing were also noted.

The perturbations in the thermohaline structure resulting from hydraulically controlled transport over the sill were clearly observed. Both convectional mixing in the intermediate layers as well as the formation of mesoscale structures were recorded.

The objective of this paper is to describe and make a preliminary analysis of the dynamic processes related to the transport of the inflowing, dense water in the bottom layers. The various phenomena will be described in greater detail in subsequent publications.

Numerical studies of the influence of the nutrient regeneration mechanism on the chlorophyll a concentration in a stratified sea
Oceanologia 1997, no. 39 (1), pp. 55–82

Keywords: Biological model, Phytoplankton, Regeneration, Nutrient Manuscript received January 2, 1997, in final form February 2, 1997.

Abstract

This paper presents numerical simulations of variability in such biological processes as nutrient uptake by phytoplankton, nutrient release, nutrient remineralisation within the water column and nutrients excreted by zooplankton, and the effect of these processes on the distribution functions of chlorophyll a and nutrient concentration in a stratified sea. The influence of these processes on the distribution functions was recorded in the changes in biological and chemical parameters, such as the factor limiting production increase, the maximum rate of production increase, the function characterising the vertical distribution of zooplankton and the coefficients n_z, n_f and n_e of the material being grazed. The numerical studies were carried out using a two–dimensional biological upper layer model (phytoplankton–phosphate) with a well-developed regeneration mechanism. This paper presents the vertical distributions of these biological characteristics in order to facilitate a better understanding of temporal changes, albeit under the assumption that the above processes are horizontally uniform. The calculations were made in an area of 0 z 20 m with a vertical space step of 10 cm and a time step of 15 min. The complex experimental data, gathered during the international experiment PEX ´86, and subsequently by the International Council for the Exploration of the Sea, were used as the input data for the calculations.

Distribution of polynuclear aromatic hydrocarbons (PAHs) in sediments of the southern Baltic Sea
Oceanologia 1997, no. 39 (1), pp. 83–104

Keywords: PAHs, Sediments, Baltic Sea, Phytoplankton, Pigments, HPLC Manuscript received January 7, 1997, in final form February 10, 1997.

Abstract

Polynuclear aromatic hydrocarbons (PAHs) were determined by a diode-array HPLC method in recent (0–10 cm) sediments collected from the southern Baltic Sea in 1994–1996. The sum of the concentrations of 12 unsubstituted PAHs were from 10 to 7000 ng g ^-1 (d.w.) (av. 1830 ng g ^-1). It is proposed that, besides the most abundant individual PAHs and `total PAH´ values, which cannot be compared owing to the different sampling and analytical methods used, a marker of pyrogenic pollution such as benzo(a)pyrene should be regarded as obligatory by all the laboratories dealing with environmental PAHs. The concentration of benzo(a)pyrene in the sediments examined ranged from 0.3 to 418 ng g ^-1 (d.w.) (av. 98 ng g ^-1). Comparison of the correlation coefficients for PAH concentrations with phytoplankton pigments and organic carbon in Baltic sediments indicates that phytoplankton is the factor principally responsible for the transport of PAHs from the water to the southern Baltic sediments.

Dissertations

An optical model of the atmosphere for satellite research of the Baltic Sea (review by J. Olszewski)
Oceanologia 1997, no. 39 (1), pp. 105–106

Ph. D. thesis in marine physics supervised by Associate Professor Jerzy Olszewski.

Application of the lidar method to determine the influence of dynamic atmospheric conditions on the concentrations and particle size distribution functions of the marine aerosol (review by K. Korzeniewski)
Oceanologia 1997, no. 39 (1), pp. 107–108

Ph. D. thesis in physical oceanography supervised by Professor Krzysztof Korzeniewski.

Identification of fatty acids and their occurrence in the southern Baltic ecosystem (review by J. Pempkowiak)
Oceanologia 1997, no. 39 (1), pp. 109–110

Ph. D. thesis in chemical oceanography supervised by Professor Janusz Pempkowiak.