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Journal of Environmental Sciences 2010年第8期22卷 1144-1150页

作者： Dominika Saniewska Magdalena Beldowska Jacek Beldowski Micha Saniewski Justyna Kwasniak Lucyna Falkowska Institute of Oceanography University of Gdansk Institute of Oceanology Polish Academy of Sciences Institute of Meteorology and Water Management Maritime Branch

The aim of this study was to characterize mercury （Hg） contamination in the coastal waters of the Southern baltic sea, and to investigate transformations of Hg in the initial links of the marine food chain. Concentrations of Hg in water, particulate matter, plankton and macrophytes at various stations in the coastal zone （a bay with restricted water exchange, near an industrial city, river mouths, and the open sea） were measured in 2006–2008. Hg concentrations observed in the Southern baltic varied greatly, showing the highest average values in all environmental compartments near the river mouths. In shallow, sheltered parts of the gulf, where water exchange is restricted, Hg concentrations in the water and in macrophytes were elevated relative to those in the coastal zone of the deeper part of the bay and in the open baltic. Distance to the river mouth, terrestrial runoff, and quantity and quality of organic matter were more important than seasonal variations in controlling Hg and HgSPM concentrations in water samples. Mercury concentrations in the surface microlayer at the air/sea interface were over 10 times higher than those in the bulk surface water. Concentrations of Hg in macrophytes in the winter were significantly higher than those in the warm seasons （spring, summer, autumn）. This was probably the combined effect of higher availability of Hg in porewaters and leaf growth inhibition.

关键词： mercury baltic sea coastal zone water particulate matter plankton macrophytes

A sensitivity study of the WRF model in offshore wind modeling over the baltic sea

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Geoscience Frontiers 2021年第6期12卷 209-222页

作者： Huidong Li Björn Claremar Lichuan Wu Christoffer Hallgren Heiner Körnich Stefan Ivanell Erik Sahlée Department of Earth Sciences Uppsala UniversityUppsala 75236Sweden Swedish Meteorological and Hydrological Institute Norrköping 60176Sweden

Accurate wind modeling is important for wind resources assessment and wind power forecasting. To improve the WRF model configuration for the offshore wind modeling over the baltic sea, this study performed a sensitivity study of the WRF model to multiple model configurations, including domain setup,grid resolution, sea surface temperature, land surface data, and atmosphere-wave coupling. The simulated offshore wind was evaluated against LiDAR observations under different wind directions, atmospheric stabilities, and sea status. Generally, the simulated wind profiles matched observations, despite systematic underestimations. Strengthening the forcing from the reanalysis data through reducing the number of nested domains played the largest role in improving wind modeling. Atmosphere-wave coupling further improved the simulated wind, especially under the growing and mature sea *** the vertical resolution, and updating the sea surface temperature and the land surface information only had a slight impact, mainly visible during very stable conditions. Increasing the horizontal resolution also only had a slight impact, most visible during unstable conditions. Our study can help to improve the wind resources assessment and wind power forecasting over the baltic sea.

关键词： Offshore wind modeling Sensitivity study Atmosphere-wave coupling WRF baltic sea

Tidal modeling based on satellite altimetry observations of TOPEX/ Poseidon, Jason1, Jason2, and Jason3 with high prediction capability: A case study of the baltic sea

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Geodesy and Geodynamics 2024年第4期15卷 404-418页

作者： Alireza A.Ardalan Asiyeh Hashemifaraz School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal *** generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each *** tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series *** study focuses on developing 1256 time series along the altimetry tracks over the baltic sea,each with its own set of tidal *** of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 *** same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,*** addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary *** encourage the satellite altimetry community to utilize these resources for further research and applications.

关键词： Satellitealtimetry baltic sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/Poseidon EOT20 FES2014

The effects of mean sea level rise and strengthened winds on extreme sea levels in the baltic sea

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Theoretical & Applied Mechanics Letters 2018年第6期8卷 366-371,I0003页

作者： Magnus Hieronymus Christian Dieterich Helén Andersson Robinson Hordoir Swedish Meteorological and Hydrological Institute Folkborgsvaen 18NorrkoingSweden

Mean sea level rise and climatological wind speed changes occur as part of the ongoing climate change and future projections of both variables are still highly uncertain. Here the baltic sea’s response in extreme sea levels to perturbations in mean sea level and wind speeds is investigated in a series of simulations with a newly developed storm surge model based on the nucleus for European modeling of the ocean(NEMO)-Nordic. A simple linear model with only two tunable parameters is found to capture the changes in the return levels extremely well. The response to mean sea level rise is linear and nearly spatially uniform, meaning that a mean sea level rise of 1 m increases the return levels by a equal amount everywhere. The response to wind speed perturbations is more complicated and return levels are found to increase more where they are already high. This behaviour is alarming as it suggests that already flooding prone regions like the Gulf of Finland will be disproportionally adversely affected in a future windier climate.

关键词： Extreme sea levels sea level rise Wind speeds baltic sea

Object-based Classification of baltic sea Ice Extent and Concentration in Winter 2011

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Journal of Earth Science and Engineering 2012年第8期2卷 488-495页

作者： Aleksandra Mazur Adam Krezel Institute of Oceanography University of Gdahsk Gdynia 81-378 Poland

The baltic sea is a brackish, mediterranean sea located in the middle latitudes of Europe. It is seasonally covered with ice. The ice covered areas during a typical winter are the Bothnian Bay, the Gulf of Finnland and the Gulf of Riga. sea ice plays an important role in dynamic and thermodynamic processes and also has a strong impact on the heat budget of the sea. Also a large part of transport goes by sea, and there is a need to create ice charts to make the marine transport safe. Because of high cloudiness in winter season and small amount of light in the northern part of the baltic sea, radar data are the most important remote sensing source of sea ice information. The main goal of the following studies is classification of the baltic sea ice cover using radar data. The ENVISAT ASAR （Advanced Synthetic Aperture Radar） acquires data in five different modes. In the following studies ASAR Wide Swath Mode data were used. The Wide Swath Mode, using the ScanSAR technique provides medium resolution images （150 m） over a swath of 405 kin, at HH or VV polarization. In following work data from February 13th, February 24th and April 6th, 2011, representing three different sea ice situations were chosen. OBIA （object-based image analysis） methods and texture parameters were used to create sea ice extent and sea ice concentration charts. Based on object-based methods, it can separate single sea ice floes within the ice pack and calculate more accurately sea ice concentration.

关键词： baltic sea sea ice ENVISAT ASAR object-based image analysis.

Linkages between Arctic sea ice cover,large-scale atmospheric circulation,and weather and ice conditions in the Gulf of Bothnia,baltic sea

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Advances in Polar Science 2014年第4期25卷 289-299页

作者： Timo Vihma Bin Cheng Petteri Uotila WEI Lixin QIN Ting Finnish Meteorological Institute(FMI) HelsinkiFinland National Marine Environmental Forecasting Centre(NMEFC)

During years 1980/1981-2012/2013, inter-annual variations in sea ice and snow thickness in Kemi, in the northern coast of the Gulf of Bothnia, baltic sea, depended on the air temperature, snow fall, and rain. Inter-annual variations in the November--April mean air temperature, accumulated total precipitation, snow fall, and rain, as well as ice and snow thickness in Kemi and ice concentration in the Gulf of Bothnia correlated with inter-annual variations of the Pacific Decadal Oscillation （PDO）, Arctic Oscillation （AO）, North Atlantic Oscillation （NAO）, Scandinavian Pattern （SCA）, and Polar / Eurasian Pattern （PEU）. The strong role of PDO is a new finding. In general, the relationships with PDO were approximately equally strong as those with AO, but rain and sea ice concentration were better correlated with PDO. The correlations with PDO were, however, not persistent; for a study period since 1950 the correlations were much lower. During 1980/1981--2012/2013, also the Pacific / North American Pattern （PNA） and E1 Nino-Southern Oscillation （ENSO） had statistical connections with the conditions in the Gulf of Bothnia, revealed by analyzing their effects combined with those of PDO and AO. A reduced autumn sea ice area in the Arctic was related to increased rain and total precipitation in the following winter in Kemi. This correlation was significant for the Pan-Arctic sea ice area in September, October, and November, and for the November sea ice area in the Barents / Kara seas.

关键词： Arctic Arctic Oscillation baltic sea North Atlantic Oscillation Pacific Decadal Oscillation,precipitation sea ice snow

Climate-Induced Variability of sea Level in Stockholm: Influence of Air Temperature and Atmospheric Circulation

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Advances in Atmospheric Sciences 2005年第5期22卷 655-664页

作者： Deliang CHEN Anders OMSTEDT Earth Sciences Centre Goteborg University Sweden Laboratory for Climate Studies/National Climate Center China Meteorological Administration Beijing 100081

This study is focused on climate-induced variation of sea level in Stockholm during 1873-1995. After the effect of the land uplift, is removed, the residual is characterized and related to large-scale temperature and atmospheric circulation. The residual shows an overall upward trend, although this result depends on the uplift rate used. However, the seasonal distribution of the trend is uneven. There are even two months （June and August） that show a negative trend. The significant trend in August may be linked to fresh water input that is controlled by precipitation. The influence of the atmospheric conditions on the sea level is mainly manifested through zonal winds, vorticity and temperature. While the wind is important in the period January-May, the vorticity plays a main role during June and December. A successful linear multiple-regression model linking the climatic variables （zonal winds, vorticity and mean air temperature during the previous two months） and the sea level is established for each month. An independent verification of the model shows that it has considerable skill in simulating the variability.

关键词： sea level baltic sea atmospheric circulation temperature Stockholm

Inter-comparisons of thermodynamic sea-ice modeling results using various parameterizations of radiative flux

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Acta Oceanologica Sinica 2006年第1期25卷 21-31页

作者： ZHANG Zhanhai CHENG Bin LAUNIAINEN Jouko WU Huiding LIU Yu State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China Finnish Institute of Marine Research Helsinki Fin-00931 Finland National Marine Environment Forecast Center Beijing 100081 China

Radiative fluxes are of primary importance in the energy and mass balance of the sea-ice cover. Various parameterizations of the radiative fluxes are studied in a thermodynamic sea-ice model. Model outputs of the surface radiative and heat fluxes and mass balance are compared with observations. The contribution of short-wave radiation is limited to a long part of winter. Therefore, simple schemes are often sufficient. Errors in estimations of the short-wave radiation are due mainly to cloud effects and occasionally to multi-reflection between surface and ice crystals in the air. The long-wave radiation plays an important role in the ice surface heat and mass balance during most part of a winter. The effect of clouds on the accuracy of the simple radiative schemes is critical, which needs further attention. In general, the accuracy of an ice model depends on that of the radiative fluxes.

关键词： parameterizations of radiative fluxes energy balance at the surface of ice/snow thermodynamic sea-ice model baltic sea Bohai sea

The role of culture for coastal disaster risk reduction measures:Empirical evidence from northern and southern Europe

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Advances in Climate Change Research 2020年第4期11卷 297-309页

作者： Grit MARTINEZ Susana COSTAS Oscar FERREIRA Ecologic Institute Berlin10717Germany Centro de Investigacao Marinha e Ambiental(CIMA) Universidade do AlgarveFaro8005-139Portugal Centro de Investigacao Marinha e Ambiental(CIMA) Faculty of Sciences and TechnologyUniversidade do AlgarveFaro8005-139Portugal

Recent and historic high-impact events have demonstrated significant flood risks to many coastal areas in Europe and across the *** the behavior of humans in relation to risk management poses grand challenges for both natural and social sciences and *** study analyzes the cultural aspects of coastal risk management and illustrates path-dependencies of concrete disaster risk reduction measures in relation to local contexts in European coastal regions in Northern and South Western *** adopts a comparative approach by targeting risk perception and risk management related to coastal floods and erosion,induced by storms and sea level rise,in two contrasting coastal areas:German coastal state SchleswigeHolstein at the baltic sea(especially the communities Eckernf€orde and Timmendorfer Strand)and the Portuguese barrier island system of Ria Formosa(especially the community of Faro Beach).Both regions are very low lying with only a few meters above sea level and exposed to similar hazards such as erosion and floods induced by coastal storms,and while they are both attractive touristic destinations,they are culturally,socio-economically and politically very *** geographical and the socio-cultural contexts of the case study regions are assessed first using an explorative approach,followed by an analysis of the relevance of cultural aspects for the implementation of disaster risk reduction *** study addresses both first responders(city authorities,citizens)and *** is found that the choice of risk reduction measures hinges on the values underlying people's perspectives about the desired outcomes of specific measures and that the role of identity and meaning making are still undervalued in decision making *** concludes that subjective capacities formed by cultural identities,knowledge,trust coupled with a variety of factors of socio-economic and political texture are important to understand local decision making

关键词： Culture Values Knowledge Risk perception Disaster risk reduction measures Coastal zones baltic sea Atlantic

Geologic framework as a factor controlling coastal morphometry and *** Spit, Lithuania

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International Journal of Sediment Research 2017年第4期32卷 597-603页

作者： Darius Jarmalavicius Gintautas Zilinskas Donatas Pupienis Nature Research Centre

The geologic framework is an important factor worth consideration when analyzing the development of seacoasts. The different coastal responses to hydrometeorological and anthropogenic factors depend on the composition and amount of original coast-forming sediments. The impact of sediment composition on morphometric parameters is best observed in areas where sand unrepresentative of the adjacent coastal sectors appears on beaches with a relatively uniform lithological composition. These areas are referred to as lithological anomalies. Large amounts of coarse-grained sand, uncharacteristic of the adjacent coastal sectors of the Curonian spit, accumulated in the area of the strait that existed in the Post-Littorina Late Subboreal(3.7-2.5 ka BP) time south of the Juodkrante settlement. Due to accumulation of coarse sand, the beach in this sector is narrow and has a higher slope, and the ridge is lower and with a smaller volume of sand than in the adjacent coastal sectors. The specific sand composition and morphology of this coastal sector are responsible for different coastal dynamics during storms. During extreme storms, beach erosion in this coastal sector is minimal(sometimes even accretion takes place)compared with other sectors where beach erosion is rather substantial. Meanwhile, during periods of relatively calm weather, i.e. times of expected regeneration of the cross profile, this sector stands out for active erosion processes.

关键词： Beach morphometry Coastal erosion Sand composition baltic sea