Wyniki wyszukiwania - BazTech

1

Studying the Sensitivity of Satellite Altimetry, Tide Gauge and GNSS Observations to Changes in Vertical Displacements

Pająk Katarzyna, Kowalczyk Kamil, Kaminskis Jānis, Idzikowska Magdalena

Geomatics and Environmental Engineering

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2021

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Vol. 15, no. 4

45--58

EN

Tide gauge observations provide sea level relative to the Earth’s crust, while satellite altimetry measures sea level variations relative to the centre of the Earth’s mass. Local vertical land motion can be a significant contribution to the measured sea level change. Satellite altimetry was traditionally used to study the open ocean, but this technology is now being used over inland seas too. The difference of both observations can be used to estimate vertical crustal movement velocities along the sea coast. In this paper, vertical crustal movement velocities were investigated at tide gauge sites along the Adriatic Sea coast by analyzing differences between Tide Gauge (TG) and Satellite Altimetry (SA) observations. Furthermore, the estimated vertical motion rates were compared with those from nearby GNSS measurements. The study determines the practical relationships between these vertical crustal movements and those determined from unrelated data acquired from the neighbouring GNSS stations. The results show general consistence with the present geodynamics in the Adriatic Sea coastal zone.

2

Estimation of Sea Level Rise in Santos Port (Brazil)

Alfredini P., Arasaki E.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

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Vol. 13, no. 2

453--458

EN

Santos Port is located in São Paulo State Coast (Brazil), in an estuarine area inside Santos Bay named Baixada Santista. The currents behavior is forced by tides. The resulting tidal level variability (high tide, mean sea level and low tide) recorded from Santos Dock Company tide gauge (1940 to 2014), the longest series of continuous record of tides in Brazil, shows a consistent increasing trend. The estimation about the magnitude of mean sea level rise (MSLR) in recommendations, guidelines or requirements issued by different countries and agencies from 1990 provide examples of different approaches used around the world in comparison with the local trends obtained for Santos Port. It is concluded that MSLR will have a considerable impact upon the port, with approximately 1.0 m rise estimated from 1990 to 2100. Baixada Santista is a lowland situated a few meters upper from the sea level and some areas are possible to be submerged in the end of this century. Other two locations in São Paulo State Coast, Cananeia and Ubatuba, respectively to the SE and NW of Santos, were also compared with the port tidal data to evaluate the consistency of the trends.

3

Estimation and impacts of sea level rise in Santos Port and Adjacent Areas (Brazil)

Alfredini P., Arasaki E.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2018

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Vol. 12, no. 4

739--744

EN

Santos Port is located in Brazilian coast, in an estuarine area inside Santos Bay named Baixada Santista. The currents behavior is forced by tides. The resulting tidal level variability (high tide, mean sea level and low tide) recorded from Santos Dock Company tide gauge (1940 to 2014) shows a consistent increasing trend. The estimation about the magnitude of mean sea level rise (MSLR) in recommendations, guidelines or requirements issued by different countries and agencies from 1990 provide examples of different approaches used around the world in comparison with the local trends obtained for Santos Port. It is concluded that MSLR will have a considerable impact upon the port and adjacent areas, with approximately 1.0 m rise estimated from 1990 to 2100. Baixada Santista is a lowland situated a few meters upper from the sea level and some areas are possible to be submerged in the end of this century. Not only the wetlands of mangroves will be affected, but also the infrastructures, residential zones and the port will face problems. The major SLR impacts upon port operation will be the reduction of freeboard of the quays, flooding of storage yards (and other low storage areas) and of the internal transport tracks or rails. Also the increasing sedimentation in the nautical areas of access channels, turning basins and berths, will induce more maintenance dredging.

4

Study of vertical movements of the European crust using tide gauge and GNSS observations

Tretyak K., Dosyn S.

Reports on Geodesy and Geoinformatics

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2014

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Vol. 97

112--131

EN

This research is devoted to the study of vertical movements of the European crust on the basis of two independent methods, namely tide gauge and GNSS observations results. The description and classification of factors affecting sea level change has been made. The precision with which the movement of the earth's crust according to the results of tide gauge observations can be explored has been calculated. A methodology to identify the duration of tide gauge observations required for studies of vertical movements of the earth's crust has been presented. Approximation of tide gauge time series with the help of Fourier series has been implemented, the need for long-term observations in certain areas has been explained. The diagram of the velocities of the vertical movements of the European crust on the basis of the tide gauge data and GNSS observations has been built and the anomalous areas where the observations do not coincide have been identified.

5

Tide gauge records-derived variations of Baltic Sea level in terms of geodynamics

Kryński J., Zanimonskiy Y. M.

Geodezja i Kartografia

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2004

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T. 53, z. 2

85-98

EN

Sea level monitoring at tide gauges plays an important role in geodesy, geodynamics research and oceanography. It provides data for referencing vertical datum, for modelling geoid in coastal regions, for determination of vertical land movements and for studying ocean dynamics. Investigation of Baltic Sea level variations is considered an important component of geodynamics research in Central and Northern Europe. The analysis of tide gauge records from Baltic sites was conducted in the framework of the project on a cm geoid in Poland. Those records showed strong common features that were further used for deriving the model of Baltic Sea level variations. High level of correlations of the model with individual site data proved its adequacy. Regional characteristics of the model were investigated using regression and correlation analysis. It was shown that the model represents very well both global and regional features of Baltic Sea level variations. The use of the model as reference to investigate local features of tide gauge records that reflect site-specific variations of sea level was also discussed. Spectral analysis of the model of Baltic Sea level variations indicates the existence of distinguished term of Chandler period besides two major terms of annual and semi-annual periods. The existence ot polar motion component in Baltic Sea level variations was investigated using correlation analysis. Also the land vertical movement derived from Baltic tide gauge data was determined and compared with literature data.

PL

Monitorowanie poziomu morza w oparciu o dane mareograficzne jest istotnym elementem badań geodezyjnych, geodynamicznych i oceanograficznych. Dostarcza ono informacji wykorzystywanych do określania poziomu odniesienia systemów wysokościowych, modelowania geoidy w obszarach nadmorskich, badania ruchów skorupy ziemskiej oraz badania dynamiki oceanów. Badanie zmian poziomu Morza Bałtyckiego stanowi ważny element studiów geodynamicznych na obszarze Centralnej i Północnej Europy. W ramach projektu badawczego, dotyczącego wyznaczenia centymetrowej geoidy na obszarze Polski, przeprowadzono analizę ciągów czasowych obserwacji mareografich ze stacji w basenie Morza Bałtyckiego. W oparciu o wspólne cechy zaobserwowane w ciągach czasowych z różnych stacji mareograficznych opracowany został model zmienności poziomu Morza Bałtyckiego. 0 poprawności opracowanego modelu świadczy wysoki stopień jego skorelowania z danymi mareograficznymi z poszczególnych stacji. Regionalne charakterystyki modelu badano przy użyciu metod regresji i analizy korelacyjnej. Pokazano, że model odzwierciedla zarówno globalne jak i lokalne cechy zmienności poziomu Morza Bałtyckiego. Dyskutowane były rownież możliwości użycia opracowanego modelu jako odniesienia do badania w mareograficznych ciągach czasowych lokalnych cech, które odzwierciedlają specyficzne dla konkretnej stacji zmiany poziomu morza. Z analizy spektralnej modelu zmienności poziomu Morza Bałtyckiego wynika, iż w zmiennościach tych, obok zasadniczych wyrazów okresowych o okresach rocznym i półrocznym, występuje wyraźny wyraz o okresie Chandlera. Obecność w zmienności poziomu Morza Bałtyckiego składowej charakterystycznej dla nutacji swobodnej była badana przy użyciu analizy korelacyjnej. Na podstawie danych mareograficznych ze stacji z basenu Morza Bałtyckiego wyznaczono rownież parametry pionowego ruchu kontynentalnego, które są zgodne z odpowiednimi parametrami dostępnymi w literaturze.