Determining the Variability of the Territorial Sea Baseline on the Example of Waterbody Adjacent to the Municipal Beach in Gdynia

Mindykowski

et al. 2020

Remote Sensing

A tombolo is a narrow belt connecting a mainland with an island lying near to the shore, formed as a result of sand and gravel being deposited by sea currents, most often created as a result of natural phenomena. However, it can also be caused by human activity, as is the case with the Sopot pier—a town located on the southern coast of the Baltic Sea in northern Poland (φ = 54°26’N, λ = 018°33’E). As a result, the seafloor rises constantly and the shoreline moves towards the sea. Moreover, there is the additional disturbing phenomenon consisting of the rising seafloor sand covering over the waterbody’s vegetation and threatening the city's spa character. Removal of the sand to another place has already been undertaken several times. There is a lack of precise geospatial data about the tombolo’s seafloor course, its size and spatial shape caused by only lowering the seafloor in random places, and the ongoing environmental degradation process. This article presents the results of extensive and integrated geodetic and hydrographic measurements, the purpose of which was to make a 3D model of the phenomena developing in Sopot. The measurements will help determine the size and speed of the geospatial changes. Most of the modern geodetic and hydrographic methods were used in the study of these phenomena. For the construction of the land part of geospatial model, the following were used: photos from the photogrammetric flight pass (unmanned aerial vehicle—UAV), laser scanning of the beach and piers, and satellite orthophotomaps for analysis of the coastline changes. In the sea part, bathymetric measurements were carried out with an unmanned surface vehicle (USV).

Section: Hydrographic Measurement Resultsmentioning

confidence: 99%

Geospatial Modeling of the Tombolo Phenomenon in Sopot using Integrated Geodetic and Hydrographic Measurement Methods

Mindykowski

et al. 2020

Remote Sensing

“…It should be noted that depths of the area located between the coastline and the 0.3 m isobath (determined by the minimum range of the echo sounder) have been interpolated due to the lack of real measurement data. Additionally, besides the DTM model, isobaths were created at 0.5 m intervals, which were presented in the form of smooth curves using the spline method [46]. Finally, it was decided to add the orthophotomap provided by the ESRI company to the DTM and the isobaths marked on it (Figure 6).…”

Section: The Correction ∆D CD Which Is Determined Based On the Following Equation Requires Additional Explainationmentioning

confidence: 99%

“…In addition to modeling, the basic method for describing the tombolo phenomenon is obtaining geospatial data by bathymetric surveys (using manned vehicles) and geodetic measurements, where a surveyor uses a GNSS receiver for the seabed determination [46]. To date, the unmanned aerial and surface vehicles have not been previously used for measurements of the geospatial features of the tombolo phenomenon.…”

Section: Introductionmentioning

confidence: 99%

Methodology for Carrying out Measurements of the Tombolo Geomorphic Landform Using Unmanned Aerial and Surface Vehicles near Sopot Pier, Poland

Lewicka

et al. 2020

JMSE

The human impact on the ecosystem has been particularly evident in the last century; it transforms the Earth’s surface on an unprecedented scale and brings about irreversible changes. One example is an oceanographic phenomenon known as a tombolo, i.e., a narrow belt connecting the mainland with an island lying near the shore formed as a result of sand and gravel being deposited by sea currents. The phenomenon contributes to an increase in the biogenic substance content in the littoral zone, which leads to increased cyanobacteria blooming in the summer period. Moreover, the debris accumulation in the littoral zone results in the mud formation, which makes the beach landscape less attractive. One of the main features of the tombolo phenomenon is its variability of shape, which includes the form of both the shore and the seabed adjacent to it. Therefore, to describe its size and spatio-temporal variability, it is necessary to apply methods for geodetic (the land) and hydrographic (the sea) measurements that can be carried out in different ways. The aim of the paper is to present the methodology for carrying out measurements of the tombolo oceanographic phenomenon using Unmanned Aerial Vehicles (UAV) and Unmanned Surface Vehicles (USV) on the example of a waterbody adjacent to the Sopot pier. It also presents the results of surveys carried out in November 2019 within this area. The study demonstrated that the integration of two measuring devices whose development began in the second decade of the 20th century, i.e., UAVs and USVs, enables accurate (even up to several centimeters) and reliable determination of the scale and variability of the phenomena occurring in the littoral zone.

“…Nevertheless, with the current development of survey and mapping methodologies, there are various new methods that can be used to determine the position of these basepoints, especially when the availability of historical tide measurements is limited. Moreover, there is no internationally recognized standard method for determining the position of this archipelagic baselines (Specht, Specht, Waz, Dabrowski, et al, 2019). However, the minimum quality of these measurements can be referred to in the IHO guidelines (IHO., 2008).…”

Section: Introductionmentioning

confidence: 99%

Integrating Multisource of Bathymetry Data for Updating Basepoint and Baseline Positions of Maritime Boundary

Dewi¹,

RACHMA²,

Sofian³

et al. 2021

The research presents an alternative method to update the position of basepoints and baselines of maritime boundary especially for the area with lack of bathymetry data. We used multisource bathymetry data for instance the national bathymetry, the national digital elevation model, and echosounding measurement data. We then integrated them with satellite derived bathymetry to provide a dense depth point in shallow water. In this case, data limitation due to the difficulty in reaching for example the outermost location was overcome by using remote sensing technology. The spline interpolation-based method was successful to integrate those multisource data and obtained quite detail information and less noisy bathymetry data. Furthermore, the LAT and HAT coastlines were able to update the positions of basepoint and baseline in the study area. We developed a new maritime boundary consisting of a normal baseline and straight lines across the mouth of three rivers and integrate them with the existing archipelagic baselines. The results can be used as a basis knowledge to support negotiations in delimiting maritime boundaries so that a proportionate and equitable agreement with neighboring countries can be achieved.