Wyniki wyszukiwania

1

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Effect of ship shadow on in-water irradiance measurements

100%

Piskozub J.

Oceanologia

|

2004

|

tom 46

|

nr 1

Calculations of the effect of the ship’s shadow on in-water irradiance measurement errors were performed with a Monte Carlo radiance transfer algorithm. The algorithm contained the Cox-Munk wave-slope probability function. A simple 3-D model of the rectangular underwater part of a ship was used. The effect was calculated as a function of sea-water absorption, surface roughness (depending on an assumed wind velocity of up to 15 m s−1) with various wind velocities and directions, length and depth of the ship, distance of instrument from the ship, and bow-to-sun angle.

2

Maximum effects of sunlight focusing under a wind-disturbed sea surface

86%

Dera J., Stramski D.

Oceanologia

|

1986

|

tom 23

3

On a possibility of remote evaluation of some optical properties of sea-water

86%

Olszewski J.

Oceanologia

|

1986

|

tom 23

4

Spectral dependence of the correlation between the backscattering coefficient and the volume scattering function measured in the Southern Baltic Sea

86%

Freda W.

Oceanologia

|

2012

|

tom 54

|

nr 3

Direct measurements of the backscattering coefficient bb require the determination of the Volume Scattering Function (VSF) and its integration over a backward hemisphere. In sea water they are difficult and are therefore carried out very rarely. That is why the backscattering coefficient is much more frequently obtained with so-called single angle scattering meters: these operate by measuring the VSF for a fixed angle region of the backward hemisphere. This article examines the spectral variability of the correlation between directly measured backscattering coefficients and VSFs. Also presented are the averaged slopes of VSF spectra, measured in southern Baltic waters over a wide range of scattering angles.

5

The effect of daylight diffuseness on the focusing of sunlight by sea surface waves

86%

Stramski D.

Oceanologia

|

1986

|

tom 24

6

A method of measurement of simpliﬁed directional distribution of radiance

86%

Olszewski J.

Oceanologia

|

1984

|

tom 18

7

Sky glint correction in measurements of upward radiance above the sea surface

86%

Olszewski J., Kowalczuk P.

Oceanologia

|

2000

|

tom 42

|

nr 2

An experiment has been performed to determine the upward water-leaving radiance by non-contact measurement of the total upward and downward radiance above the sea surface from a moving ship. The method for achieving this aim is described: the radiance meters are both tilted in such a way that the upward radiance meter can ‘see’ that part of the measured downward radiance which would be reflected if the water surface were smooth and which is not derived directly from solar glitter. Both meters are firmly fixed in a special frame, which ensures that the required orientation is the most probable one. Time records of the measured parameters are analysed. The results are presented in several forms: frequency (histogram) analysis appears to be the most promising one.

8

In-water remote sensing algorithms for the detection of chlorophyll and yellow substances in the Pomeranian Bay

86%

Olszewski J., Kowalczuk P., Darecki M.

Oceanologia

|

1999

|

tom 41

|

nr 3

9

Derivation of remote sensing reflectance of Baltic waters from above-surface measurements

86%

Olszewski J., Darecki M.

Oceanologia

|

1999

|

tom 41

|

nr 1

10

The progress in knowledge of physical oceanography of the Gulf of Finland: e review for 1997-2007

72%

Soomere T., Myrberg K., Lepparanta M., Nekrasov A.

Oceanologia

|

2008

|

tom 50

|

nr 3

287-362

The main findings of studies of the physical oceanography of the Gulf of Finland (GoF) during 1997–2007 are reviewed. The aim is to discuss relevant updates published in international peer-reviewed research papers and monographs, bearing in mind that a comprehensive overview of the studies up to the mid-1990s is available (Alenius et al. 1998). We start the discussion with updates on the basic hydrographical and stratification conditions, and progress in the understanding of atmospheric forcing and air-sea interaction. Advances in the knowledge of basinscale and mesoscale dynamics are summarised next. Progress in circulation and water exchange dynamics has been achieved mostly by means of numerical studies. While the basic properties of circulation patterns in the gulf have been known for a century, new characteristics and tools such as water age, renewal index, and high-resolution simulations have substantially enriched our knowledge of processes in the Gulf of Finland during the last decade. We present the first overview of both status and advances in optical studies in this area. Awareness in this discipline has been significantly improved as a result of in situ measurements. Our understanding of the short- and long-term behaviour of the sea level as well as knowledge of the properties of both naturally and anthropogenically induced surface waves have expanded considerably during these ten years. Developments in understanding the ice conditions of the Gulf of Finland complete the overview, together with a short discussion of the gulf’s future, including the response to climate change. Suggestions for future work are outlined.

11

The impact of fast ferry traffic on underwater optics and sediment resuspension

72%

Erm A., Soomere T.

Oceanologia

|

2006

|

tom 48

|

nr S

Wake waves produced by fast ferries bring about significant changes in the optical parameters of sea water in the c. 1 m thick near-bottom layer of the coastal areas of Tallinn Bay. The greatest of these changes occur at relatively small depths, but the duration of the influence increases with increasing depth. Rough quantitative estimates suggest that the overall influence of fast ferry traffic in Tallinn Bay may result in an annual loss of the order of several hundred litres of fine sediments from each metre of the coastline.

12

Radiance reflectance of homogeneous plane parallel layers

72%

Domsta J.

Oceanologia

|

1993

|

tom 34

13

SatBaltyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 2: Practical applicability and preliminary results

58%

Wozniak B., Bradtke K., Darecki M., Dera J., Dudzinska-Nowak J., Dzierzbicka-Glowacka L., Ficek D., Furmanczyk K., Kowalewski M., Krezel A., Majchrowski R., Ostrowska M., Paszkuta M., Ston-Egiert J., Stramska M., Zapadka T.

Oceanologia

|

2011

|

tom 53

|

nr 4

This paper is the second part of the description of the first stage of the SatBałtyk project’s implementation. Part 1 (Woźniak et al. 2011, in this issue) presents the assumptions and objectives of SatBałtyk and describes the most important stages in the history of our research, which is the foundation of this project. It also discusses the operation and general structure of the SatBałtyk system. Part 2 addresses various aspects of the practical applicability of the SatBałtyk Operational System to Baltic ecosystem monitoring. Examples are given of the Baltic’s characteristics estimated using the preliminary versions of the algorithms in this Operational System. At the current stage of research, these algorithms apply mainly to the characteristics of the solar energy influx and the distribution of this energy among the various processes taking place in the atmosphere-sea system, and also to the radiation balance of the sea surface, the irradiance conditions for photosynthesis and the condition of plant communities in the water, sea surface temperature distributions and some other marine phenomena correlated with this temperature. Monitoring results obtained with these preliminary algorithms are exemplified in the form of distribution maps of selected abiotic parameters of the Baltic, as well as structural and functional characteristics of this ecosystem governed by these parameters in the Baltic’s many basins. The maps cover practically the whole area of the Baltic Sea. Also given are results of preliminary inspections of the accuracy of the magnitudes shown on the maps. In actual fact, the errors of these estimates are relatively small. The further practical application of this set of algorithms (to be gradually made more specific) is therefore entirely justified as the basis of the SatBałtyk system for the effective operational monitoring of the state and functioning of Baltic ecosystems. This article also outlines the plans for extending SatBałtyk to include the recording of the effects and hazards caused by current and expected storm events in the Polish coastal zone.

14

Revisiting the role of oceanic phase function in remote sensing reflectance

58%

Freda W., Piskozub J.

Oceanologia

|

2012

|

tom 54

|

nr 1

The effect of angular structure differences between measured and best-fit analytical phase functions of the equivalent backscattering ratio on calculated reflectance values was studied and shown to be significant. We used a Monte Carlo radiative transfer code to check the effect of choosing different analytical (several Fournier- Forand (1994) and Henyey-Greenstein (1941)) phase functions with backscattering ratios identical to the ‘classical’ average Petzold function. We show that the additional variability of the resulting water leaving radiance is about 7% (4% between the Fournier-Forand functions themselves) for most scenarios. We also show a previously unknown maximum of the discrepancy (up to 10%) for highly scattering waters. We discuss the importance of relative differences in phase function for different angular ranges to this maximum and to the behaviour of the discrepancy as a function of solar zenith angle.

15

SatBałtyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 1: Assumptions, scope and operating range

58%

Wozniak B., Bradtke K., Darecki M., Dera J., Dudzinska-Nowak J., Dzierzbicka-Glowacka L., Ficek D., Furmanczyk K., Kowalewski M., Krezel A., Majchrowski R., Ostrowska M., Paszkuta M., Ston-Egiert J., Stramska M., Zapadka T.

Oceanologia

|

2011

|

tom 53

|

nr 4

This article is the first of two papers on the remote sensing methods of monitoring the Baltic ecosystem, developed by a Polish team. The main aim of the five- year SatBałtyk (2010–2014) research project (Satellite Monitoring of the Baltic Sea Environment) is to prepare the technical infrastructure and set in motion operational procedures for the satellite monitoring of the Baltic environment. This system is to characterize on a routine basis the structural and functional properties of this sea on the basis of data supplied by the relevant satellites. The characterization and large-scale dissemination of the following properties of the Baltic is anticipated: the solar radiation influx to the sea’s waters in various spectral intervals, energy balances of the short- and long-wave radiation at the Baltic Sea surface and in the upper layers of the atmosphere over the Baltic, sea surface temperature distribution, dynamic states of the water surface, concentrations of chlorophyll a and other phytoplankton pigments in the Baltic water, distributions of algal blooms, the occurrence of upwelling events, and the characteristics of primary organic matter production and photosynthetically released oxygen in the water. It is also intended to develop and, where feasible, to implement satellite techniques for detecting slicks of petroleum derivatives and other compounds, evaluating the state of the sea’s ice cover, and forecasting the hazards from current and future storms and providing evidence of their effects in the Baltic coastal zone. The ultimate objective of the project is to implement an operational system for the routine determination and dissemination on the Internet of the above-mentioned features of the Baltic in the form of distribution maps as well as plots, tables and descriptions characterizing the state of the various elements of the Baltic environment. The main sources of input data for this system will be the results of systematic recording by environmental satellites and also special-purpose ones such as TIROS N/NOAA, MSG (currently Meteosat 9), EOS/AQUA and ENVISAT. The final effects of the SatBałtyk project are to be achieved by the end of 2014, i.e. during a period of 60 months. These two papers present the results obtained during the first 15 months of the project. Part 1 of this series of articles contains the assumptions, objectives and a description of the most important stages in the history of our research, which constitute the foundation of the current project. It also discusses the way in which SatBałtyk functions and the scheme of its overall operations system. The second article (Part 2), will discuss some aspects of its practical applicability in the satellite monitoring of the Baltic ecosystem (see Woźniak et al. (2011) in this issue).

16

Spatial and temporal changes in some optical parameters in the southern Baltic

58%

Olszewski J., Sagan S., Darecki M.

Oceanologia

|

1992

|

tom 33

17

Professor Bogdan Wozniak (1946—2014)

43%

Dera J.

Oceanologia

|

2015

|

tom 57

|

nr 1

Ograniczanie wyników

Effect of ship shadow on in-water irradiance measurements

Maximum effects of sunlight focusing under a wind-disturbed sea surface

On a possibility of remote evaluation of some optical properties of sea-water

Spectral dependence of the correlation between the backscattering coefficient and the volume scattering function measured in the Southern Baltic Sea

The effect of daylight diffuseness on the focusing of sunlight by sea surface waves

A method of measurement of simpliﬁed directional distribution of radiance

Sky glint correction in measurements of upward radiance above the sea surface

In-water remote sensing algorithms for the detection of chlorophyll and yellow substances in the Pomeranian Bay

Derivation of remote sensing reflectance of Baltic waters from above-surface measurements

The progress in knowledge of physical oceanography of the Gulf of Finland: e review for 1997-2007

The impact of fast ferry traffic on underwater optics and sediment resuspension

Radiance reflectance of homogeneous plane parallel layers

SatBaltyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 2: Practical applicability and preliminary results

Revisiting the role of oceanic phase function in remote sensing reflectance

SatBałtyk – A Baltic environmental satellite remote sensing system – an ongoing project in Poland. Part 1: Assumptions, scope and operating range

Spatial and temporal changes in some optical parameters in the southern Baltic

Professor Bogdan Wozniak (1946—2014)