Temat: sensing - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Numerical simulations of sea ice conditions in the Baltic Sea for 2010–2016 winters using the 3D CEMBS model
Autorzy:: Janecki, M.
Nowicki, A.
Kańska, A.
Golenko, M.
Dzierzbicka-Głowacka, L.
Powiązania:: https://bibliotekanauki.pl/articles/260518.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: Baltic Sea
sea ice
numerical modelling
remote sensing
climate change
Opis:: Sea ice conditions in the Baltic Sea during six latest winters – 2010/2011 to 2015/2016 are analysed using coupled ice– ocean numerical model 3D CEMBS (3D Coupled Ecosystem Model of the Baltic Sea). Simulation results are compared with observations from monitoring stations, ice charts and satellite data. High correlation between model results and observations has been confirmed both in terms of spatial and temporal approach. The analysed period has a high interannual variability of ice extent, the number of ice days and ice thickness. Increasing number of relatively mild winters in the Northern Europe directly associated with climate change results in reduced ice concentration in the Baltic Sea. In this perspective, the implementation and development of the sea ice modelling approach (in addition to standard monitoring techniques) is critical to assess current state of the Baltic Sea environment and predict possible climate related changes in the ecosystem and their influence for human marine–related activities, such as fishery or transportation.
Źródło:: Polish Maritime Research; 2018, 3; 35-43
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: Quantum yield of photosynthesis in the Baltic: a new mathematical expression for remote sensing applications
Autorzy:: Wozniak, B.
Ficek, D.
Ostrowska, M.
Majchrowski, R.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/49078.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
application
phytoplankton photosynthesis
photosynthesis quantum yield
Baltic Sea
Opis:: Statistical relationships between the quantum yield of photosynthesis Φ and selected environmental factors in the Baltic have been established on the basis of a large quantity of empirical data. The model formula is the product of the theoretical maximum quantum yield ΦMAX =0.125 atomC quantum−1 and five dimensionless factors fi taking values from 0 do 1: Φ = ΦMAXfa fΔ fc(Ca(0)) fc(PARinh) fE, t. To a sufficiently good approximation, each of these factors fi appears to be dependent on one or at most two environmental factors, such as temperature, underwater irradiance, surface concentration of chlorophyll a, absorption properties of phytoplankton and optical depth. These dependences have been determined for Baltic Case 2 waters. The quantum yield Φ, calculated from known values of these environmental factors, is then applicable in the model algorithm for the remote sensing of Baltic primary production. The statistical error of the approximate quantum yields Φ is 62%.
Źródło:: Oceanologia; 2007, 49, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: SeaWiFS-derived products in the Baltic Sea: performance analysis of a simple atmospheric correction algorithm
Autorzy:: Bulgarelli, B.
Melin, F.
Zibordi, G.
Powiązania:: https://bibliotekanauki.pl/articles/47664.pdf
Data publikacji:: 2003
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: ocean colour
remote sensing
accuracy analysis
Baltic Sea
atmospheric correction
Opis:: The accuracyan alysis of an approximate atmospheric correction algorithm for the processing of SeaWiFS data has been investigated for the Baltic Sea. The analysis made use of theoretical radiances produced with the FEM radiative transfer code for representative atmosphere-water test cases. The studysho wed uncertainties in the determination of the aerosol optical thickness at 865 nm and of the ˚Angstr¨om exponent lower than ±5% and ±10%, respectively. These results were confirmed bythe analysis of 59 match-ups between satellite-derived and in situ measurements for a site located in the central Baltic. Because of the relativelyhig h yellow substance absorption, often combined with the slanted solar illumination, the retrieval of the water-leaving radiance in the blue part of the spectrum appeared to be highlyd egraded, to the extent that almost no correlation was found between retrieved and simulated values. Better results were obtained at the other wavelengths. The accuracyin the estimation of the remote sensing reflectance ratio R35 decreased with diminishing chlorophyll a concentration and increasing yellow substance absorption, ranging between ±7% and ±47%. The propagation of R35 uncertainties on chlorophyll a estimation was quantified. Keeping the same atmosphere-water conditions, the atmospheric correction scheme appeared sensitive to seasonal changes in the Sun zenith.
Źródło:: Oceanologia; 2003, 45, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: Spectra of light absorption by phytoplankton pigments in the Baltic; conclusions to be drawn from a Gaussian analysis of empirical data
Autorzy:: Ficek, D.
Kaczmarek, S.
Ston-Egiert, J.
Wozniak, B.
Majchrowski, R.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/47835.pdf
Data publikacji:: 2004
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: phytoplankton pigment
remote sensing algorithm
Baltic Sea
Gaussian analysis
light absorption
Opis:: Analysed by differential spectroscopy, 1208 empirical spectra of light absorption apl(λ) by Baltic phytoplankton were spectrally decomposed into 26 elementary Gaussian component bands. At the same time the composition and concentrations of each of the 5 main groups of pigments (chlorophylls a, chlorophylls b, chlorophylls c, photosynthetic carotenoids and photoprotecting carotenoids) were analysed in 782 samples by HPLC. Inspection of the correlations between the intensities of the 26 elementary absorption bands and the concentrations of the pigment groups resulted in given elementary bands being attributed to particular pigment groups and the spectra of the mass-specific absorption coefficients established for these pigment groups. Moreover, balancing the absorption effects due to these 5 pigment groups against the overall absorption spectra of phytoplankton suggested the presence of a sixth group of pigments, as yet unidentified (UP), undetected by HPLC. Apr eliminary mathematical description of the spectral absorption properties of these UP was established. Like some forms of phycobilins, these pigments are strong absorbers in the 450–650 nm spectral region. The packaging effect of pigments in Baltic phytoplankton was analysed statistically, then correlated with the concentration of chlorophyll a in Baltic water. As a result, a Baltic version of the algorithm of light absorption by phytoplankton could be developed. This algorithm can be applied to estimate overall phytoplankton absorption spectra and their components due to the various groups of pigments from a knowledge of their concentrations in Baltic water.
Źródło:: Oceanologia; 2004, 46, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 5.

Tytuł:: Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 1: Total chlorophyll a distribution
Autorzy:: Ostrowska, M.
Majchrowski, R.
Ston-Egiert, J.
Wozniak, B.
Ficek, D.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/47972.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
phytoplankton pigment
chlorophyll a
vertical distribution
concentration
Baltic Sea
distribution
Opis:: This article is the first in a series of three describing the modelling of the vertical different photosynthetic and photoprotecting phytoplankton pigments concentration distributions in the Baltic and their interrelations described by the so-called non-photosynthetic pigment factor. The model formulas yielded by this research are an integral part of the algorithms used in the remote sensing of the Baltic ecosystem. Algorithms of this kind have already been developed by our team from data relating mainly to oceanic Case 1 waters (WC1) and have produced good results for these waters. But their application to Baltic waters, i.e., Case 2 waters, was not so successful. On the basis of empirical data for the Baltic Sea, we therefore derived new mathematical expressions for the spatial distribution of Baltic phytoplankton pigments. They are discussed in this series of articles. This first article presents a statistical model for determining the total concentration of chlorophyll a (i.e., the sum of chlorophylls a+pheo derived spectrophotometrically) at different depths in the Baltic Sea Ca(z) on the basis of its surface concentration Ca(0), which can be determined by remote sensing. This model accounts for the principal features of the vertical distributions of chlorophyll concentrations characteristic of the Baltic Sea. The model’s precision was verified empirically: it was found suitable for application in the efficient monitoring of the Baltic Sea. The modified mathematical descriptions of the concentrations of accessory pigments (photosynthetic and photoprotecting) in Baltic phytoplankton and selected relationships between them are given in the other two articles in this series (Majchrowski et al. 2007, Woźniak et al. 2007b, both in this volume).
Źródło:: Oceanologia; 2007, 49, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 6.

Tytuł:: Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 3: Non-phytosynthetic pigment absorption factor
Autorzy:: Wozniak, B.
Majchrowski, R.
Ostrowska, M.
Ficek, D.
Kunicka, J.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/48371.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
pigment distribution
phytoplankton pigment
vertical distribution
non-photosynthetic pigment absorption
Baltic Sea
Opis:: This paper, part 3 of the description of vertical pigment distributions in the Baltic Sea, discusses the mathematical expression enabling the vertical distributions of the non-photosynthetic pigment absorption factor fa to be estimated. The factor fa is directly related to concentrations of the several groups of phytoplankton pigments and describes quantitatively the ratio of the light energy absorbed at given depths by photosynthetic pigments to the light energy absorbed by all the phytoplankton pigments together (photosynthetic and photoprotecting). Knowledge of this factor is highly desirable in the construction of state-of-the-art ‘light-photosynthesis’ models for remote-sensing purposes. The expression enables fa to be estimated with considerable precision on the basis of two surface parameters (available from satellite observations): the total chlorophyll a concentration at the surface Ca(0) and the spectral downward irradiance Ed(λ, 0) just below the sea surface. The expression is applicable to Baltic waters from the surface down to an optical depth of τ ≈5. The verification of the model description of fa was based on 400 quasi-empirical values of this factor which were calculated on the basis of empirical values of the following parameters measured at the same depths: Ed(λ, z) (or also PAR(z)), apl(λ, z), and the concentrations of all the groups of phytoplankton pigments Ca(z) and Cj(z) (where j denotes in turn chl b, chl c, PSC, phyc, PPC). The verification shows that the errors in the values of the non-photosynthetic pigment absorption factor fa estimated using the model developed in this work are small: in practice they do not exceed 4%. Besides the mathematical description of the vertical distribution of fa, this paper also discusses the range of variation of its values measured in the Baltic and its dependence on the trophic index of a basin and depth in the sea. In addition, the similarities and differences in the behaviour of fa in Baltic and oceanic basins are compared.
Źródło:: Oceanologia; 2007, 49, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 7.

Tytuł:: Influence of coastal upwelling on chlorophyll a concentration in the surface water along the Polish coast of the Baltic Sea
Autorzy:: Krezel, A.
Szymanek, L.
Kozlowski, L.
Szymelfenig, M.
Powiązania:: https://bibliotekanauki.pl/articles/49088.pdf
Data publikacji:: 2005
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: surface water
chlorophyll a
satellite remote sensing
concentration
coastal upwelling
Baltic Sea
Polish coast
Opis:: Space-time variations in chlorophyll a (Chl a) concentrations in the surface water of upwelling regions along the Polish coast of the Baltic Sea were analysed. Carried out between 1998 and 2002 in the warmer season (from April till October), the measurements were targeted mainly at the Hel upwelling. Satellite-derived sea surface temperature (AVHRR) and Chl a data (SeaWiFS) were used. Generally speaking, the Chl a concentration increased in the upwelling plume, except along the Hel Peninsula, where two scenarios took place: a reduction in Chl a concentration in spring and an increase in autumn.
Źródło:: Oceanologia; 2005, 47, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 8.

Tytuł:: A simple model of light transmission through the atmosphere over the Baltic Sea utilising satellite data
Autorzy:: Krezel, A.
Kozlowski, L.
Paszkuta, M.
Powiązania:: https://bibliotekanauki.pl/articles/48356.pdf
Data publikacji:: 2008
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: sea surface
Baltic Sea
solar energy
atmosphere
light transmission
satellite remote sensing
aerosol optical thickness
Opis:: A simple spectral model of solar energy input to the sea surface was extended to incorporate space-borne data. The extension involved finding a method of determining aerosol optical thickness (on the basis of AVHRR data) and the influence of cloudiness (on the basis of METEOSAT data) on the solar energy flux. The algorithm for satellite data assimilation involves the analysis of satellite images from the point of view of cloud identification and their classification with respect to light transmission. Solar energy input values measured at the Earth’s surface by traditional methods were used to calibrate and validate the model. Preliminary evaluation of the results indicates a substantial improvement in the accuracy of estimates of solar energy input to the sea surface in relation to models utilising only traditionally obtained data on the state of the atmosphere.
Źródło:: Oceanologia; 2008, 50, 2; 125-146
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 9.

Tytuł:: Testing the performance of empirical remote sensing algorithms in the Baltic Sea waters with modelled and in situ reflectance data
Autorzy:: Ligi, M.
Kutser, T.
Kallio, K.
Attila, J.
Koponen, S.
Paavel, B.
Soomets, T.
Reinart, A.
Powiązania:: https://bibliotekanauki.pl/articles/48045.pdf
Data publikacji:: 2017
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
algorithm
Baltic Sea
coastal water
chlorophyll a
optical property
phytoplankton assemblage
water reflectance
Opis:: Remote sensing studies published up to now show that the performance of empirical (band-ratio type) algorithms in different parts of the Baltic Sea is highly variable. Best performing algorithms are different in the different regions of the Baltic Sea. Moreover, there is indication that the algorithms have to be seasonal as the optical properties of phytoplankton assemblages dominating in spring and summer are different. We modelled 15,600 reflectance spectra using HydroLight radiative transfer model to test 58 previously published empirical algorithms. 7200 of the spectra were modelled using specific inherent optical properties (SIOPs) of the open parts of the Baltic Sea in summer and 8400 with SIOPs of spring season. Concentration range of chlorophyll-a, coloured dissolved organic matter (CDOM) and suspended matter used in the model simulations were based on the actually measured values available in literature. For each optically active constituent we added one concentration below actually measured minimum and one concentration above the actually measured maximum value in order to test the performance of the algorithms in wider range. 77 in situ reflectance spectra from rocky (Sweden) and sandy (Estonia, Latvia) coastal areas were used to evaluate the performance of the algorithms also in coastal waters. Seasonal differences in the algorithm performance were confirmed but we found also algorithms that can be used in both spring and summer conditions. The algorithms that use bands available on OLCI, launched in February 2016, are highlighted as this sensor will be available for Baltic Sea monitoring for coming decades.
Źródło:: Oceanologia; 2017, 59, 1
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: Laboratory measurements of remote sensing reflectance of selected phytoplankton species from the Baltic Sea
Autorzy:: Soja-Wozniak, M.
Darecki, M.
Wojtasiewicz, B.
Bradtke, K.
Powiązania:: https://bibliotekanauki.pl/articles/47866.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
reflectance
phytoplankton
diatom
Cyclotella meneghiniana
Skeletonema marinoi
Cyanoprokaryota
Dolichospermum
Nodularia spumigena
Synechococcus
Baltic Sea
Opis:: Results of unique laboratory measurements of remote sensing reflectance (Rrs) of several phytoplankton species typically occurring in high abundances in the Baltic Sea waters are presented. Reflectance spectra for diatoms: Cyclotella meneghiniana and Skeletonema marinoi and Dolichospermum sp., Nodularia spumigena and sp. were analysed in terms of assessment of their characteristic features and the differences between them. These species contain similar pigments, which results in general similarities of reflectance spectra, i.e. decrease of reflectance magnitude in the blue and red spectrum regions. However, hyper-spectral resolution of optical measurements let us find differences between optical signatures of diatoms and cyanobacteria groups and between species belonging to one group as well. These differences are reflected in location of local maxima and minima in the reflectance spectrum and changes in relative height of characteristic peaks with changes of phytoplankton concentration. Wide ranges of phytoplankton concentrations were analysed in order to show the persistence of Rrs characteristic features. The picoplankton species, Synechococcus sp. show the most distinct optical signature, which let to distinguish separate cluster in hierarchical cluster analysis (HCA). The results can be used to calibrate input data into radiative transfer model, e.g. phase function or to validate modelled Rrs spectra.
Źródło:: Oceanologia; 2018, 60, 1
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: Light absorption by phytoplankton in the Southern Baltic and Pomeranian lakes: mathematical expressions for remote sensing applications
Autorzy:: Meler, J.
Ostrowska, M.
Ficek, D.
Zdun, A.
Powiązania:: https://bibliotekanauki.pl/articles/48072.pdf
Data publikacji:: 2017
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: light absorption
phytoplankton
absorption property
surface water
Baltic Sea
Pomeranian lake
photosynthetic pigment
chlorophyll a
remote sensing
Opis:: The absorption properties of phytoplankton in surface waters of the Baltic Sea and coastal lakes are examined in the context of their relationships with the concentration of the main photosynthetic pigment, chlorophyll a. The analysis covers 425 sets of spectra of light absorption coefficients aph(l) and chlorophyll a concentrations Chla measured in 2006—2009 in various waters of the Baltic Sea (open and coastal waters, the Gulf of Gdańsk and the Pomeranian Bay, river mouths and the Szczecin Lagoon), as well as in three lakes in Pomerania, Poland (Obłęskie, Łebsko and Chotkowskie). In these waters the specific (i.e. normalized with respect to Chla) light absorption coefficient of phytoplankton aph *(l) varies over wide ranges, which differ according to wavelength. For example, aph *(440) takes values from 0.014 to 0.124 mg1 m2, but aph *(675) from 0.008 to 0.067 mg1 m2, whereby Chla ranges from 0.8 to 120 mg m3. From this analysis a mathematical description has been produced of the specific light absorption coefficient of phytoplankton aph *(l), based on which the dynamics of its variability in these waters and the absorption spectra in the 400—700 nm interval can be reconstructed with a low level of uncertainty (arithmetic statistical error: 4.09—10.21%, systematic error: 29.63—51.37%). The relationships derived here are applicable in local remote sensing algorithms used for monitoring the Baltic Sea and coastal lakes and can substantially improve the accuracy of the remotely determined optical and biogeochemical characteristics of these waters.
Źródło:: Oceanologia; 2017, 59, 3
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: In situ measurements and satellite remote sensing of case 2 waters: first results from the Curonian Lagoon
Autorzy:: Giardino, C.
Bresciani, M.
Pilkaityte, R.
Bartoli, M.
Razinkovas, A.
Powiązania:: https://bibliotekanauki.pl/articles/48042.pdf
Data publikacji:: 2010
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: satellite remote sensing
satellite image
water
Curonian Lagoon
eutrophication
calibration
validation
eutrophic ecosystem
aquatic ecosystem
Baltic Sea
Opis:: In this study we present calibration/validation activities associated with satellite MERIS image processing and aimed at estimating chl a and CDOM in the Curonian Lagoon. Field data were used to validate the performances of two atmospheric correction algorithms, to build a band-ratio algorithm for chl a and to validate MERIS-derived maps. The neural network-based Case 2 Regional processor was found suitable for mapping CDOM; for chl a the band-ratio algorithm applied to image data corrected with the 6S code was found more appropriate. Maps were in agreement with in situ measurements. This study confirmed the importance of atmospheric correction to estimate water quality and demonstrated the usefulness of MERIS in investigating eutrophic aquatic ecosystems.
Źródło:: Oceanologia; 2010, 52, 2; 197-210
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 13.

Tytuł:: Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 2: Accessory pigment distribution
Autorzy:: Majchrowski, R.
Ston-Egiert, J.
Ostrowska, M.
Wozniak, B.
Ficek, D.
Lednicka, B.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/48281.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
accessory pigment concentration
pigment distribution
chlorophyll a
phytoplankton pigment
vertical distribution
Baltic Sea
marine ecosystem
distribution
Opis:: This is the second in a series of articles, the aim of which is to derive mathematical expressions describing the vertical distributions of the concentrations of different groups of phytoplankton pigments; these expressions are necessary in the algorithms for the remote sensing of the marine ecosystem. It presents formulas for the vertical profiles of the following groups of accessory phytoplankton pigments: chlorophylls b, chlorophylls c, phycobilins, photosynthetic carotenoids and photoprotecting carotenoids, all for the uppermost layer of water in the Baltic Sea with an optical depth of τ ≈ 5. The mathematical expressions for the first four of these five groups of pigments, classified as photosynthetic pigments, enable their concentrations to be estimated at different optical depths in the sea from known surface concentrations of chlorophyll a. The precision of these estimates is characterised by the following relative statistical errors according to logarithmic statistics σ−: approximately 44% for chlorophyll b, approx. 39% for chlorophyll c, approx. 43% for phycobilins and approx. 45% for photosynthetic carotenoids. On the other hand, the mathematical expressions describing the vertical distributions of photoprotecting carotenoid concentrations enable these to be estimated at different depths in the sea also from known surface concentrations of chlorophyll a, but additionally from known values of the irradiance in the PAR spectral range at the sea surface, with a statistical error σ− of approximately 42%
Źródło:: Oceanologia; 2007, 49, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 14.

Tytuł:: Validation of empirical and semi-analytical remote sensing algorithms for estimating absorption by Coloured Dissolved Organic Matter in the Baltic Sea from SeaWiFS and MODIS imagery
Autorzy:: Kowalczuk, P.
Darecki, M.
Zablocka, M.
Gorecka, I.
Powiązania:: https://bibliotekanauki.pl/articles/47876.pdf
Data publikacji:: 2010
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: validation
remote sensing
Ocean colour
satellite validation
coloured dissolved organic matter
organic matter
absorption
Baltic Sea
Gdansk Gulf
Vistula River
Opis:: An extensive bio-optical data set obtained from field measurements was used to evaluate the performance of an empirical (Kowalczuk et al. 2005) and two semi- analytical algorithms: Carder et al. (1999) and GSM01 (Maritorena et al. 2002) for estimating CDOM absorption in the Baltic Sea. The data set includes coincident measurements of radiometric quantities and absorption coefficients of CDOM made during 43 cruises between 2000 and 2008. In the first stage of the analysis, the accuracy of the empirical algorithm by Kowalczuk et al. (2005) was assessed using in situ measurements of remote sensing reflectance. Validation results improved when matching points located in Gulf of Gdańsk close to the Vistula River mouth were eliminated from the data set. The calculated errors in the estimation of aCDOM(400) in the first phase of the analysis were Bias = −0.02, RMSE = 0.46 and R2 = 0.70. In the second stage, the empirical algorithm was tested on satellite data from SeaWiFS and MODIS imagery. The satellite data were corrected atmospherically with the MUMM algorithm designed for turbid coastal and inland waters and implemented in the SeaDAS software. The results of the best case scenario for estimating the CDOM absorption coefficient aCDOM(400), based on SeaWiFS data, were Bias = −0.02, RMSE = 0.23 and R2 = 0.40. The validation of the Kowalczuk et al. (2005) empirical algorithm applied to MODIS data led to a less accurate estimate of aCDOM(400): Bias = −0.03, RMSE = 0.19 and R2 = 0.29. This assessment of the accuracy of standard semi-analytical algorithms available in the SeaWiFS and MODIS imagery processing software revealed that both algorithms (GSM 01 and Carder) underestimate CDOM absorption in the Baltic Sea with mean systematic and random errors in excess of 70%. The paper presents examples of the application of the Kowalczuk et al. (2005) empirical algorithm for producing maps of the seasonal distribution of aCDOM(400) in the Baltic Sea between 2004 and 2008.
Źródło:: Oceanologia; 2010, 52, 2; 171-196
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki