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This study presents 62 years of hindcast wave climate data for the south coast of Sweden from 1959–2021. The 100-km-long coast consists mainly of sandy beaches and eroding bluffs interrupted by headlands and harbours alongshore, making it sensitive to variations in incoming wave direction. A SWAN wave model of the Baltic Sea, extending from the North Sea to the Åland Sea, was calibrated and validated against wave observations from 16 locations distributed within the model domain. Wave data collected from open databases were complemented with new wave buoy observations from two nearshore locations within the study area at 14 and 15 m depth. The simulated significant wave height showed good agreement with the local observations, with an average R2 of 0.83. The multi-decadal hindcast data was used to analyse spatial and temporal wave climate variability. The results show that the directional distribution of incoming waves varies along the coast, with a gradually increasing wave energy exposure from the west towards the east. The wave climate is most energetic from October to March, with the highest wave heights in November, December, and January. In general, waves from westerly directions dominate the annual wave energy, but within the hindcast time series, a few years had larger wave energy from easterly directions. The interannual variability of total wave energy and wave direction is correlated to the North Atlantic Oscillation (NAO) index. In the offshore, the total annual wave energy had a statistically significant positive correlation with the NAO DJFM station-based index, with a Spearman rank correlation coefficient of 0.51. In the nearshore, the correlation was even stronger. Future studies should investigate the possibility of using the NAO index as a proxy for the wave energy direction and its effect on coastal evolution., Coastal Engineering

Combining hard and soft costal protection solutions can be an appropriate measure to enhance structure lifetime. This study aims to quantify the morphological evolution of the nourished stretch and adjacent coastlines. A small-scale beach nourishment has been performed in front of a rock revetment at site in Faxe Ladeplads in Zealand, Denmark. The overall objective is to learn more about the dynamics of small-scale nourishments in low energy environments. Monitoring techniques include repeated topographic (Trimble RTK-GPS, drone surveying) and bathymetric (single beam) measurements. To measure the hydrodynamic conditions two surface acceleration buoys deployed at -4 and -7 m water depth were used. Sediment volumes from nourishments of size 70,000 m3 and 20,000 m3 redistributed relatively quickly. The nourished material built up the cross-shore profile and a longshore bar in this area, and distributed sediments in the direction of the dominant littoral drift (SW). Results suggest that the morphological evolution of the nourishment is dependent on local hydrodynamic conditions and local geomorphology. These findings have implications for the main objectives of preventing wave overtopping onto an adjacent coastal road during extreme events and restoring a beach for recreation.

Combining hard and soft costal protection solutions can be an appropriate measure to enhance structure lifetime. This study aims to quantify the morphological evolution of the nourished stretch and adjacent coastlines. A small-scale beach nourishment has been performed in front of a rock revetment at site in Faxe Ladeplads in Zealand, Denmark. The overall objective is to learn more about the dynamics of small-scale nourishments in low energy environments. Monitoring techniques include repeated topographic (Trimble RTK-GPS, drone surveying) and bathymetric (single beam) measurements. To measure the hydrodynamic conditions two surface acceleration buoys deployed at -4 and -7 m water depth were used. Sediment volumes from nourishments of size 70,000 m3 and 20,000 m3 redistributed relatively quickly. The nourished material built up the cross-shore profile and a longshore bar in this area, and distributed sediments in the direction of the dominant littoral drift (SW). Results suggest that the morphological evolution of the nourishment is dependent on local hydrodynamic conditions and local geomorphology. These findings have implications for the main objectives of preventing wave overtopping onto an adjacent coastal road during extreme events and restoring a beach for recreation.

Sjötrafik har alltid haft en stor betydelse för vårt samhälle genom att transportera gods och människor mellan och inom länder. Transporter till sjöss har stora fördelar associerat till relativt låga klimatutsläpp och transportkostnader. Tyvärr medför sjötrafik även en negativ påverkan på vår miljö. Den negativa påverkan kan till exempel bestå av utsläpp av luftföroreningar, tömning av ballastvatten eller utsläpp av olja. I farleder kan fartyg även inverka på de hydrodynamiska förhållandena genom att generera strömmar och vågor. Fartygsvågor kan resultera i skador på stränder och konstruktioner vid vattnet, öka grumlingen i vattnet, eller till och med innebära en fara för människor som vistas i eller på vattnet. Särskilt stor blir påverkan från fartygsvågor i farleder som naturligt inte utsätts för vindvågor. Det gäller farleder inomskärs, i vattendrag och i sjöar. Fartygsvågor kan här utgöra ett betydande tillskott till de totala vågkrafterna som påverkar stränderna. Om vågorna är tillräckligt stora och frekventa kan de orsaka erosion av stränderna. Denna effekt kan minskas genom att sänka fartygens hastighet, ändra fartygsrutter, begränsa storleken på fartygen eller förstärka stränderna med erosionsskydd. En farled där påverkan av fartygs- och båttrafik varit påtaglig under en lång tid är Furusundsleden i Stockholms skärgård. Furusundsleden är en viktig farled med reguljär trafik av passagerarfärjor till Åland, Finland och Estland. Därutöver trafikeras farleden även av skärgårdstrafik och kryssningsfartyg under sommarhalvåret. Fartygserosionen i Furusundsleden har varit ett uppmärksammat problem ända sedan 1980-talet. Hastigheterna har begränsats för större fartyg med effekten av erosionen avtagit längs farleden. För vissa sträckor har hastighetsbegränsningen dock inte varit en tillräcklig åtgärd för att förhindra erosionen. Därför har tidigare utredningar föreslagit någon form av erosionsskydd längs med dessa stränder. Traditionellt har erosionsskydd i farleder u

From November 12th to 13th in 1872, an extreme coastal flood event occurred in the south Baltic Sea. An unusual combination of winds created a storm surge reaching up to 3.5 m above mean sea level, which is more than a meter higher than all other observations over the past 200 years. On the Danish, German, and Swedish coasts, about 300 people lost their lives. The consequences of the storm in Denmark and Germany were more severe than in Sweden, with significantly larger destruction and higher numbers of casualties. In Denmark and Germany, the 1872 storm has been more extensively documented and remembered and still influences local and regional risk awareness. A comparative study indicates that the collective memory of the 1872 storm is related to the background knowledge about floods, the damage extent, and the response to the storm. Flood marks and dikes help to remember the events. In general, coastal flood defence is to the largest degree implemented in the affected areas in Germany, followed by Denmark, and is almost absent in Sweden, corresponding to the extent of the collective memory of the 1872 storm. Within the affected countries, there is local variability of flood risk awareness associated with the collective memory of the storm. Also, the economic dependency on flood-prone areas and conflicting interests with the tourism industry have influence on flood protection decisions. The processes of climate change adaptation and implementation of the EU Floods Directive are slowly removing these differences in flood risk management approaches., Coastal Engineering

Wave climate data for the Swedish provinces Skane and Halland, were hindcast using SWAN, a third-generation spectral wave model. The 40-year wave dataset, from 1979 to 2019, is made available through an open-access data portal (https://gis.sgi.se/vagmodell/). The wave data has a three-hour resolution and includes significant wave height, peak wave period, and wave direction. The wave model domain encompasses the Baltic Sea, Öresund, Kattegat, and Skagerrak. Along the coast of Skane and Halland, the spatial resolution of the computational nodes, from which data can be extracted in the portal, is 250 m. In the offshore areas, the resolution of the computational grid is coarser. The simulated significant wave height was validated against observations from 25 wave gauges, operating intermittently during the simulation period. The coefficient of determination, R2, for these comparisons ranged from 0.46 to 0.93 for the different stations. For 15 wave gauges, R2 values for the comparisons exceeded 0.80. The wave model will continuously be updated and developed.

Coastal erosion is a global problem affecting almost every country in the world having a coastline. This problem is expected to accelerate in the future due to the global warming, which most likely will cause a sea level rise and increase the number of storm events around the globe. The effect from the erosion costs 700 million US dollars each year for the US alone and will increase in the future with the accelerating coastal erosion. The money used for minimizing the effects from the erosion, in a poor country like Tanzania, could instead be used to increase the living and health standards in the country. Kunduchi and the studied coastal stretch of 23 km are situated north of Dar es Salaam in Tanzania on the African east coast. In the 1980´s it was reported about severe erosion in the area. Erosion, resulting in a retreating shoreline, over hundreds of meters on several locations, and the collapse of the Africana Hotel. The setback of the beach has lead to that many of the hotel and house owners have applied different methods of shore protection. Resulting in the building of groins and seawalls, without any expertise, to protect their properties. The purpose of the study is to clarify and quantify the governing sediment transport processes in the area, quantify the historical shoreline movement, and propose suitable mitigation measures to reduce the impact of the erosion. In the present study the theory behind the beach dynamics in the area is studied along with general theories about sediment transport and shoreline formations. An extensive field visit was carried out during July and August 2007 with field measurements of beach profiles and sediment samples. A synoptical study was made of the coastal stretch, which led to an area description. Besides this, visits were made to different organisations and authorities with connection to the area and the current problem. Results from the analysis indicate that the governing transport process in the area is longshore t