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EN
The article presents estimations of coastline retreat and advance in Kaliningrad Oblast at 85 monitoring points for a ten-year period of 2007–2017, based on monitoring data supplemented with satellite image analysis. The mean annual rate of coastline retreat and advance was estimated in general for each of the four major morpholithodynamic segments of the coastline: the Vistula (􀀀0:2 m/year) and Curonian (􀀀0:4 m/year) spits, as well as the western (􀀀0:5 m/year) and northern (􀀀0:2 m/year) shores of the Sambia Peninsula. The analysis of the shore protection measures implemented in Kaliningrad Oblast from 2007 to 2017 showed that the length of protected shore segments increased by 30% to 14.5 km, which is 10% of the total coastline. The obtained scheme of long-term mean annual rates of coastline retreat and advance clearly demonstrates an uneven distribution of eroded segments along the shores of Kaliningrad Oblast, however the sea shore of Kaliningrad Oblast is mainly susceptible to erosion (44%). Accumulative segments of the shore make up only 17% of the total coastline, and the remaining 39% of the shore is relatively stable. The results obtained demonstrate that the long-term mean annual rate of coastline retreat has decreased to 􀀀0:3 m/year from 􀀀1 m/year in the earlier period of 2000–2010. The general condition of the entire coastline of Kaliningrad Oblast can therefore be described as relatively sustainable]. The changes are related to several factors, such as an increase in the length of protected shore segments, the resumption of sand pulp dumping in the beach area by the Amber Mining Plant, and an increase in the amount of analytical data from an expanded local monitoring network.
EN
In the current study we use a three-dimensional model with hydrodynamic and spectral wave modules operating in a coupled mode to simulate the response of currents and wind wave fields to winds of 20–25 m/sec offshore of the protective structure of the Saint Petersburg Flood Prevention Facility Complex. The model was calibrated against field data, which allowed us to obtain a tool describing storm situations in the eastern part of the Gulf of Finland with a satisfactory accuracy. The numerical modeling showed that the protective dam did not have a noticeable effect on the levels of stormsurge, significantwave height, or current speed in areas seaward of the dam. The increase in erosion processes on the southern shore of the easternmost part of the Gulf of Finland in recent past has most probably been related to other factors. We found that if a west or south-west wind of at least 25 m/s blows over the Baltic Sea for at least 16 hours, the level of storm surges seaward of the dam may reach 3 or more meters. An artificial strengthening of the coastline and the creation of shore protection structures are recommended.
EN
This paper presents an overview of the sub-mesoscale eddies observed in the coastal zone of the south-eastern Baltic near the shores of the Sambian Peninsula and the Curonian Spit based on CODAR (high-frequency coast-based radar) measurements and analysis of MODIS and ASAR satellite images for the period 30 March 2000-31 December 2011. It was found that when winds are predominantly SW, S or W, a wake eddy of varying size (up to 25 km in diameter) forms off Cape Taran and can cover the area between the shoreline and the 65 m isobath. Its longest lifetime, observed using MODIS images, was 6 days. Another location where coastal sub-mesoscale eddies (up to 10-15 km in diameter) of varying form regularly appear is the coastal slope near the southern and central part of the Curonian Spit.
EN
A two-dimensional numerical model was used for a simulation of vertical average longshore currents generated by both wind friction and wind-wave action in the nearshore zone. The modelling domain includes the southern part of the Baltic Proper (all boundaries were closed). Wind, uniform in space and varying in time, was the only forcing in the model. The correlation coefficient higher than 0.8 was obtained by model calibration versus the field measurements of currents conducted at the Lubiatowo field station (southern Baltic) during about 1.5 months in 2006. Comparative simulations of total currents including both wind-induced drift and wave components, and of total currents including only a wind-induced drift component, showed that the input of the drift component into currents in the nearshore zone is greater than commonly believed. Wind-induced drift strongly dominates outside the zone of wave transformation, and its input into the total resulting currents remains noticeable even in a zone between the shoreline and the depth of the first wave breaking. Thus, wind-induced drift constitutes up to 50% of the resulting longshore currents for longshore winds and no less than 20% of the longshore component of currents for winds at 45 degrees to the longshore direction.
EN
The paper studies variations in the water level and surface temperature of coastal lagoons along the southern and south-eastern shores of the Baltic Sea: the Curonian Lagoon, Vistula Lagoon, and Darss-Zingst Bodden Chain. Linear regressions for annual mean water level variations showed a positive trend in water level, but at different rates. The highest rate during the period between 1961-2008 was recorded for the Curonian and Vistula lagoons (~4 mm year-1), the lowest for the Darss-Zingst Bodden Chain (approximately ~ 1 mm year-1). The warming trend of the mean surface water temperature in the lagoons was 0.03°C year-1 in the period 1961-2008. Moreover, the variability in annual water temperature and sea level as well as their extreme values have increased most dramatically since the 1980s.
EN
This article shows how dumping of sediments from an amber mining plant prevented erosion of the western shore of the Sambian Peninsula (in Kaliningrad Oblast). The average annual dynamics of coastal areas in the vicinity of the former dumping site of the amber mining plant is described. Nowadays the erosion is continuing after cessation of dumping. The rate of erosion was estimated by results of regular monitoring measurements, using airborne laser scanning. It was found that about 250000 cubic metres per year of local material is needed every year to prevent further erosion and retreat of the shore.
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