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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The relationship between suspended particulate matter and turbidity at a mooring station in a coastal environment: consequences for satellite-derived products

100%
Jafar-Sidik M., Gohin F., Bowers D., Howarth J., Hull T.
Oceanologia
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2017
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tom 59
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nr 3
From a data set of observations of Suspended Particulate Matter (SPM) concentration, Turbidity in Formazin Turbidity Unit (FTU) and fluorescence-derived chlorophyll-a at a mooring station in Liverpool Bay, in the Irish Sea, we investigate the seasonal variation of the SPM: Turbidity ratio. This ratio changes from a value of around 1 in winter (minimum in January— February) to 2 in summer (maximum in May—June). This seasonal change can be understood in terms of the cycle of turbulence and of the phytoplankton population that affects the nature, shape and size of the particles responsible for the Turbidity. The data suggest a direct effect of phytoplankton on the SPM:Turbidity ratio during the spring bloom occurring in April and May and a delayed effect, likely due to aggregation of particles, in July and August. Based on the hypothesis that only SPM concentration varies, but not the mass-specific backscattering coefficient of particles bbp *, semi-analytical algorithms aiming at retrieving SPM from satellite radiance ignore the seasonal variability of bbp * which is likely to be inversely correlated to the SPM:Turbidity ratio. A simple sinusoidal modulation of the relationship between Turbidity and SPM with time helps to correct this effect at the location of the mooring. Without applying a seasonal modulation to bbp *, there is an underestimation of SPM in summer by the Ifremer semi-analytical algorithm (Gohin et al., 2015) we tested. SPM derived from this algorithm, as expected from any semi-analytical algorithm, appears to be more related to in situ Turbidity than to in situ SPM throughout the year.
2

Suspended particulate matter in the Hel upwelling Region [the Baltic Sea]

100%
Bradtke K., Burska D., Matciak M., Szymelfenig M.
Oceanological and Hydrobiological Studies
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2005
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tom 34
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nr Suppl.2
3
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Simple statistical formulas for estimating biogeochemical properties of suspended particulate matter in the Southern Baltic Sea potentially useful for optical remote sensing applications

84%
Wozniak S. B.
Oceanologia
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2014
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tom 56
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nr 1
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Total suspended particulate matter in the Porsanger fjord (Norway) in the summers of 2014 and 2015

84%
Bialogrodzka J., Stramska M., Ficek D., Wereszka M.
Oceanologia
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2018
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tom 60
|
nr 1
High-latitude fjords, very vulnerable to global change, are impacted by their land and ocean boundaries, and they may be influenced by terrestrial water discharges and oceanic water inputs into them. This may be reflected by temporal and spatial patterns in concentrations of biogeochemically important constituents. This paper analyses information relating to the total suspended matter (TSM) concentration in the Porsanger fjord (Porsangerfjorden), which is situated in the coastal waters of the Barents Sea. Water samples and a set of physical data (water temperature, salinity, inherent optical properties) were obtained during two field expeditions in the spring and summer of 2014 and 2015. Bio-optical relationships were derived from these measurements, enabling optical data to be interpreted in terms of TSM concentrations. The results revealed significant temporal variability of TSM concentration, which was strongly influenced by precipitation, terrestrial water discharge and tidal phase. Spatial distribution of TSM concentration was related to the bathymetry of the fjord, dividing this basin into three subregions. TSM concentrations ranged from 0.72 to 0.132 g m−3 at the surface (0–2 m) and from 0.5 to 0.67 g m−3 at 40 m depth. The average mineral fraction was estimated to be 44% at surface and 53% at 40 m.
5
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Spatiotemporal changes in the concentration and composition of suspended particulate matter in front of Hansbreen, a tidewater glacier in Svalbard

84%
Moskalik M., Cwiakala J., Szczucinski W., Dominiczak A., Glowacki O., Wojtysiak K., Zagorski P.
Oceanologia
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2018
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tom 60
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nr 4
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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UV absorption reveals mycosporine-like amino acids (MAAs) in Tatra Mountain lake phytoplankton

84%
Ficek D., Dera J., Wozniak B.
Oceanologia
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2013
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tom 55
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nr 3
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Annual spatio-temporal variation of the euphotic depth in the SW-Finnish archipelago, Baltic Sea

67%
Luhtala H., Tolvanen H., Kalliola R.
Oceanologia
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2013
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tom 55
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nr 2
8
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Sediment deposition and accumulation rates determined by sediment trap and 210Pb isotope methods in the Outer Puck Bay (Baltic Sea)

67%
Szmytkiewicz A., Zalewska T.
Oceanologia
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2014
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tom 56
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nr 1
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Improvement of MERIS level 2 products in Baltic Sea coastal areas by applying the Improved Contrast between Ocean and Land processor (ICOL) - data analysis and validation

67%
Kratzer S., Vinterhav C.
Oceanologia
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2010
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tom 52
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nr 2
211-236
In this paper we compare the following MERIS processors against sea-truthing data: the standard MERIS processor (MEGS 7.4.1), the Case 2 Regional processor (C2R) of the German Institute for Coastal Research (GKSS), and the Case 2Water Properties processor developed at the Freie Universit¨at Berlin (FUB). Furthermore, the Improved Contrast between Ocean and Land processor (ICOL), a prototype processor for the correction of adjacency effects from land, was tested on all three processors, and the retrieval of level 2 data was evaluated against sea-truthing data before and after ICOL processing. The results show that by using ICOL the retrieval of spectral reflectance in the open sea was improved for all processors. After ICOL processing, the FUB showed rather small errors in the blue, but underestimated in the red −34% Mean Normalised Bias (MNB) and 37% Root Mean Square (RMS). For MEGS the reflectance in the red was underestimated by about −20% MNB and 23% RMS, whereas the reflectance in the other channels was well predicted, even without any ICOL processing. The C2R underestimated the red with about −27% MNB and 29% RMS and at 412 nm it overestimated the reflectance with about 23% MNB and 29% RMS. At the outer open sea stations ICOL processing did not have a strong effect: the effect of the processor diminishes progressively up to 30 km from land. At the open sea stations the ICOL processor improved chlorophyll retrieval using MEGS from −74% to about 34% MNB, and TSM retrieval from −63% to about 22% MNB. Using FUB in combination with ICOL gave even better results for both chlorophyll (25% MNB and 45% RMS) and TSM (−4% MNB and 36% RMS) in the open Baltic Sea. All three processors predicted TSM rather well, but the standard processor gave the best results (−12% MNB and 17% RMS). The C2R had a very low MNB for TSM (1%), but a rather high RMS (54%). The FUB was intermediate with −16% MNB and 31% RMS. In coastal waters, the spectral diffuse attenuation coefficient Kd(490) was well predicted using FUB or MEGS in combination with ICOL (MNB about 12% for FUB and 0.4% for MEGS). Chlorophyll was rather well predicted in the open Baltic Sea using FUB with ICOL (MNB 25%) and even without ICOL processing (MNB about 15%). ICOL-processed MEGS data also gave rather good retrieval of chlorophyll in the coastal areas (MNB of 19% and RMS of 28%). In the open Baltic Sea chlorophyll retrieval gave a MNB of 34% and RMS of 70%, which may be due to the considerable patchiness caused by cyanobacterial blooms. The results presented here indicate that with the MERIS mission, ESA and co- workers are in the process of solving some of the main issues regarding the remote sensing of coastal waters: spatial resolution; land-water adjacency effects; improved level 2 product retrieval in the Baltic Sea, i.e. the retrieval of spectral reflectance and of the water quality products TSM and chlorophyll.
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Inherent optical properties of suspended particulate matter in the Southern Baltic Sea

67%
Wozniak S. B., Meller J., Lednicka B., Zdun A., Ston-Egiert J.
Oceanologia
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2011
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tom 53
|
nr 3
The inherent optical properties (IOPs) of suspended particulate matter and their relations with the main biogeochemical characteristics of particles have been examined in the surface waters of the southern Baltic Sea. The empirical data were gathered at over 300 stations in open Baltic Sea waters as well as in the coastal waters of the Gulf of Gdańsk. The measurements included IOPs such as the absorption coefficient of particles, absorption coefficient of phytoplankton, scattering and backscattering coefficients of particles, as well as biogeochemical characteristics of suspended matter such as concentrations of suspended particulate matter (SPM), particulate organic matter (POM), particulate organic carbon (POC) and chlorophyll a (Chl a). Our data documented the very extensive variability in the study area of particle concentration measures and IOPs (up to two orders of magnitude). Although most of the particle populations encoun- tered were composed primarily of organic matter (av. POM/SPM=ca 0.8), the different particle concentration ratios suggest that the particle composition varied significantly. The relations between the optical properties and biogeochemical parameters of suspended matter were examined. We found significant variability in the constituent-specific IOPs (coefficients of variation (CVs) of at least 30% to 40%, usually more than 50%). Simple best-fit relations between any given IOP versus any constituent concentration parameter also highlighted the significant statistical errors involved. As a result, we conclude that for southern Baltic samples an easy yet precise quantification of particle IOPs in terms of the concentration of only one of the following parameters – SPM, POM, POC or Chl a – is not achievable. Nevertheless, we present a set of best statistical formulas for a rough estimate of certain seawater constituent concentrations based on relatively easily measurable values of seawater IOPs. These equations can be implemented in practice, but their application will inevitably entail effective statistical errors of estimation of the order of 50% or more.
11
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Inherent optical properties and remote sensing reflectance of Pomeranian lakes (Poland)

67%
Ficek D., Meler J., Zapadka T., Wozniak B., Dera J.
Oceanologia
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2012
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tom 54
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nr 4
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Remote sensing reflectance of Pomeranian lakes and the Baltic

67%
Ficek D., Zapadka T., Dera J.
Oceanologia
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2011
|
tom 53
|
nr 4
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