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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.

2

Low Sea Level Occurrence of the Southern Baltic Sea Coast

Stanisławczyk I., Kowalska B., Mykita M.

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

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2010

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Vol. 4, no. 2

199--204

PL

The level of 440 cm is defined as the upper limit of low sea level. This value is also accepted as the warning level for navigation, according to the NAVTEX. The low sea levels along the southern Baltic Sea coast were analyzed in the years 1955 – 2005. Lowest values recorded ranged from 309 cm in Wismar to 370 cm in Kołobrzeg. The phenomenon was chiefly generated by hurricane like offshore winds. Extremely low levels were not frequent, their occurrence did not exceed more than 0,3% in Świnoujście and not more than 1% in Warnemünde. In summer months these phenomena occurred extremely seldom, they were more fre-quent in the western, than in the eastern part of the coast. Long-term variation and statistical analysis was pre-sented. Probability of low sea levels occurrence was calculated by Gumbel method and percentile distribution for 4 gauge stations was analyzed. The calculations revealed that, for instance, in Warnemünde once in 20 years the minimum sea level can be as low as 358 cm.

3

The Role of Operational Ocean Forecasting in E-Navigation

Graff J.

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

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2008

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Vol. 2, no. 3

259--262

EN

Advances in ocean modelling have led to improved performance for operational ocean forecasting and the availability of continuously reliable forecast information for certain ocean regions of the world. Although such forecasts are being increasingly adopted into a wide range of services across the maritime industry they have not yet been considered as candidates to supplement or to substitute conventional tide tables for navigation use. The issue is important in the context of climate change and the added uncertainty now placed on the use of conventional tide table for navigation in complex coastal waters. In the context of e-navigation it is timely to begin to explore the issue and examine how such forecasts might be used and adopted. This requires closer connectivity between ocean forecasting and navigation communities and the involvement of overarching organisations such as IMO and I GOOS. This paper raises the issue and opens the debate.

4

A Required Data Span to Detect Sea Level Rise

Niedzielski T., Kosek W.

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

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2008

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Vol. 2, no. 2

143--147

EN

Altimetric measurements indicate that the global sea level rises about 3 mm/year, however, in various papers different data spans are adopted to estimate this value. The minimum time span of TOPEX/Poseidon (T/P) and Jason-1 (J-1) global sea level anomalies (SLA) data required to detect a statisti-cally significant trend in sea level change was estimated. Seeking the trend in the global SLA data was per-formed by means of the Cox-Stuart statistical test. This test was supported by the stepwise procedure to make the results independent of the starting data epoch. The probabilities of detecting a statistically significant trend within SLA data were computed in the relation with data spans and significance levels of the above-mentioned test. It is shown that for the standard significance level of 0.05 approximately 5.5 years of the SLA data are required to detect a trend with the probability close to 1. If the seasonal oscillations are removed from the combined T/P and J-1 SLA data, 4.3 years are required to detect a statistically significant trend with a probability close to 1. The estimated minimum time spans required to detect a trend in sea level rise are ad-dressed to the problem of SLA data predictions. In what follows, the above-mentioned estimate is assumed to be minimum data span to compute the representative sample of SLA data predictions. The forecasts of global mean SLA data are shown and their mean prediction errors are discussed.