Biogeochemical Budgets of Nutrients and Metabolism in the Curonian Lagoon (South East Baltic Sea): Spatial and Temporal Variations

Estuaries are biogeochemical reactors able to modulate the transfer of energy and matter from the watershed to the coastal zones and to retain or remove large amounts of terrestrially generated nutrients. However, they may switch from nutrient sink to source depending upon interannual variability of the nutrient supply and internal processes driving whole system metabolism (e.g., net autotrophic or heterotrophic). We tested this hypothesis in the Curonian Lagoon, a hypertrophic estuary located in the south east Baltic Sea, following the budget approach developed in the Land-Ocean Interactions in the Coastal Zone (LOICZ) project. Annual budgets for nitrogen (N), phosphorus (P), and silica (Si) were calculated for the 2013–2015 period. The lagoon was divided in a flushed, nutrient loaded area, and in a confined, less loaded area. The lagoon was always a sink for dissolved inorganic Si and P whereas it was a N sink in the confined area, dominated by denitrification, and a N source in the flushed area, due to dinitrogen (N2) fixation. The net ecosystem metabolism (NEM) indicated that the Curonian Lagoon was mainly autotrophic because of high primary production rates. In this turbid system, low N:P ratio, high summer temperatures, and calm weather conditions support high production of N2-fixing cyanobacteria, suppressing the estuarine N-sink role.

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Timescales of emergence of chronic nuisance flooding in the major economic centre of Guadeloupe

10.5194/nhess-2020-178 ◽

2020 ◽

Author(s):

Gonéri Le Cozannet ◽

Déborah Idier ◽

Marcello de Michele ◽

Yoann Legendre ◽

Manuel Moisan ◽

...

Keyword(s):

Weather Conditions ◽

Interferometric Synthetic Aperture Radar ◽

Coastal Zones ◽

Tropical Islands ◽

Sea Levels ◽

Vertical Ground ◽

Calm Weather ◽

Flooding Events ◽

Commercial Center ◽

Local Variability

Abstract. Chronic flooding, occurring at high tides under calm weather conditions, is occasionally taking place today in the low-lying areas of the Petit-Cul-de-sac marin (Guadeloupe, West Indies, French Antilles). This area includes critical industrial, harbor and major economic infrastructures for the island. As sea level rises, concerns are growing regarding the possibility for repeated chronic flooding events, which would alter the operations at these critical coastal infrastructures without appropriate adaptation. Here, we use information on past and future sea levels, vertical ground motion and tides to assess times of emergence of chronic flooding in the Petit-Cul-de-sac marin. For RCP8.5 (i.e., continued growth of greenhouse gas emissions), the number of flood days is projected to increase rapidly after the emergence of the process, so that coastal sites will be flooded every two days within 2 decades after the onset of chronic flooding. For coastal locations with the smallest altitude, we show that the reconstructed number of floods are consistent with observations known from a previous survey. One key uncertainty of our result is the actual rate of subsidence of the island. However, our satellite interferometric synthetic-aperture radar results show that the local variability of this subsidence is smaller than the uncertainties of the technique, which we estimate between 1 (standard deviation of measurements) and 5 mm/yr (upper theoretical bound). Our results imply that adaptation pathways considering a rapid increase of recurrent chronic flooding are required in the critical port, industrial and commercial center of Guadeloupe, as well as presumably in many low-elevation coastal zones of other tropical islands.

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NEWEST TECTONICS OF THE VISTULA SPIT AREA

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b43162bdb89 ◽

2017 ◽

Author(s):

Nikolay Dunaev ◽

Nadezhda Politova ◽

Nadezhda Politova

Keyword(s):

Baltic Sea ◽

Coastal Zones ◽

Structural Principle ◽

Modern Landscape ◽

Tectonic Pattern

The interests of forecasting of the area’s development simulate to take more attention to the study of its newest tectonics. The most informative tectonic pattern for the studies of coastal zones is neotectonic one, based on the structural principle, which shows the newly formed and inherited dislocations, reflected in the modern landscape and exodynamics of the earth's surface. The question of the manifestations of newest tectonics by way on the example of the Vistula Spit (Baltic Sea) is discussed.

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Modeling Transit Flow Through Port Gates and Connecting Channel in Baltic Sea—Liepaja Port—Liepaja Lake System

Frontiers in Marine Science ◽

10.3389/fmars.2021.657721 ◽

2021 ◽

Vol 8 ◽

Author(s):

Vilnis Frishfelds ◽

Juris Sennikovs ◽

Uldis Bethers ◽

Jens Murawski ◽

Andrejs Timuhins

Keyword(s):

Baltic Sea ◽

Sea Level ◽

Sea Water ◽

Lake System ◽

The North ◽

Transit Flow ◽

Trade Channel ◽

Calm Weather ◽

Set Up ◽

The Baltic

This study investigates a water transport features by extending Copernicus Marine Environment Service (CMEMS) to the Liepaja coast-port-channel-lake system with a two-way nested model. The Liepaja lake and Liepaja port are connected by Trade channel. The Liepaja port has three gates—the openings in wave breakers connecting the port aquatory with the Baltic sea. Each of gates has a corresponding dredged channel for securing the navigation. A hydrodynamic model is set up to study the flow and water level in this system. The area of the port gates, port and Trade channel are resolved by 33 m grid. The model results are verified against currents and sea level observations inside/outside port, Trade channel and Liepaja lake. Results and observations show that strong currents occur in the Trade channel in case of rapid sea level change in Baltic sea despite the Trade channel is rather shallow at the connection with Liepaja lake. The northern part of the Liepaja lake gets filled with brackish water during storm surge events. The channel has notable alternating current also during a relatively calm weather due to the port seiches. Long and narrow shape of the channel implies the Helmholtz type oscillations between the lake and the port with a period in approximately semidiurnal range. Hydrodynamic simulations describe well these oscillations but the phase of hourly scale oscillations in the port may differ in case of weak external forcing. Water exchange is significantly increased by the transit (gate to gate) sea currents. This transit flow usually occurs between South or Central gate and the North gate carrying sea water into the port. Northward flow of the surface layer is more characteristic in the port aquatory due the prevailing south-western winds. There are intense morphological processes at the coastline and underwater slope near the Liepaja port due to a sandy western coastline of Latvia, long fetch of the waves and strong currents at the port gates. Liepaja port is one of the Latvian ports in HywasPort operational service of hydrodynamics, waves and siltation.

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MASSIVE USE OF BERM RELOCATION AND SURFWASHING DURING THE 2006 JYEH OIL SPILL (LEBANON): THE ACCURATE RESPONSE FOR BEACHES CLEANUP

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2008-1-331 ◽

2008 ◽

Vol 2008 (1) ◽

pp. 331-338 ◽

Cited By ~ 1

Author(s):

Bernard Fichaut ◽

Bahr Loubnan

Keyword(s):

Surf Zone ◽

Weather Conditions ◽

Fuel Oil ◽

Shallow Waters ◽

Power Station ◽

Heavy Fuel Oil ◽

Sediment Removal ◽

Calm Weather ◽

Oily Waste

ABSTRACT Following the bombardment of the Jyeh power station in Lebanon on July 16 2006, about 10 to 15000 tons of heavy fuel oil drifted 150 km northward all the way to the Syrian border. Because of the continuing war, the cleanup operations could not start until early September. The response consisted of conceptually dividing the coast line into several sectors managed by various operators; from Jyeh to Beyrouth, a 34.5 km stretch of shoreline, the treatment of beaches was assigned to the lebanese N.G.O “Bahr Loubnan’. In this area, 5.3 km of sandy and gravel beaches appeared to be heavily oiled on a width that seldomly exceeded 10 m. Oil was found buried down to a depth of 1.8 m at several locations. Additionnally oil was also found sunken in shallow waters in the breaker zones of numerous beaches. In order to minimize sediment removal and production of oily waste to be treated, it was decided to operate massive treatmenN in situ. After manual recovery of stranded oil, about 12,000 m of sediment including 1,000 m of cobbles have been relocated in the surf zone. Despite the lack of tides and of the generally calm weather conditions, surfwashing was very efficient due mainly to the fact that, in non tidal conditions, sediments are continuously reworked by wave açtion which operates at the same level on the beaches. Only 540 m of heavily oiled sand, was removed from beaches and submitted for further treatment. The lack of appropriate sorbents material in Lebanon to capture the floating oil released by surfwahing was also a challenge. This was addressed by using locally Nmanufactured sorbents, which proved to be very efficient and 60 m of sorbent soaked with oil were produced during the cleanup.

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Recent Progress in Applying Advanced Computation Methods to Radar-Based Wave Measurements

10.4043/31049-ms ◽

2021 ◽

Author(s):

Morten Loell Vinther ◽

Torbjørn Eide ◽

Aurelia Paraschiv ◽

Dickon Bonvik-Stone

Keyword(s):

Doppler Radar ◽

Risk Mitigation ◽

Weather Conditions ◽

Data Access ◽

Environmental Data ◽

Data Sets ◽

Wave Measurements ◽

Current Profiler ◽

Pulse Doppler ◽

Calm Weather

Abstract High quality environmental data are critical for any offshore activity relying on data insights to form appropriate planning and risk mitigation routines under challenging weather conditions. Such data are the most significant driver of future footprint reduction in offshore industries, in terms of costs savings, as well as operational safety and efficiency, enabled through ease of data access for all relevant stakeholders. This paper describes recent advancements in methods used by a dual-footprint Pulse-Doppler radar to provide accurate and reliable ocean wave height measurements. Achieved improvements during low wind weather conditions are presented and compared to data collected from other sources such as buoys and acoustic doppler wave and current profiler (ADCP) or legacy. The study is based on comparisons of recently developed algorithms applied to different data sets recorded at various sites, mostly covering calm weather conditions.

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Long-term temporal changes in the occurrence of a high forest fire danger in Finland

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-2591-2012 ◽

2012 ◽

Vol 12 (8) ◽

pp. 2591-2601 ◽

Cited By ~ 6

Author(s):

H. M. Mäkelä ◽

M. Laapas ◽

A. Venäläinen

Keyword(s):

Forest Fire ◽

Forest Fires ◽

Large Scale ◽

Weather Conditions ◽

Temporal Variations ◽

Fire Danger ◽

Specific Information ◽

Climate Data ◽

Forest Fire Danger

Abstract. Climate variation and change influence several ecosystem components including forest fires. To examine long-term temporal variations of forest fire danger, a fire danger day (FDD) model was developed. Using mean temperature and total precipitation of the Finnish wildfire season (June–August), the model describes the climatological preconditions of fire occurrence and gives the number of fire danger days during the same time period. The performance of the model varied between different regions in Finland being best in south and west. In the study period 1908–2011, the year-to-year variation of FDD was large and no significant increasing or decreasing tendencies could be found. Negative slopes of linear regression lines for FDD could be explained by the simultaneous, mostly not significant increases in precipitation. Years with the largest wildfires did not stand out from the FDD time series. This indicates that intra-seasonal variations of FDD enable occurrence of large-scale fires, despite the whole season's fire danger is on an average level. Based on available monthly climate data, it is possible to estimate the general fire conditions of a summer. However, more detailed input data about weather conditions, land use, prevailing forestry conventions and socio-economical factors would be needed to gain more specific information about a season's fire risk.

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Reduced-Order Modeling of Stratospheric Winds and Its Application in High-Altitude Balloon Trajectory Simulations

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-16-0294.1 ◽

2017 ◽

Vol 56 (6) ◽

pp. 1753-1766 ◽

Cited By ~ 6

Author(s):

Sai Sudha Ramesh ◽

Kian Meng Lim ◽

Heow Pueh Lee ◽

Boo Cheong Khoo

Keyword(s):

High Altitude ◽

Weather Conditions ◽

Temporal Variations ◽

Weather Data ◽

Compact Representation ◽

Station Keeping ◽

Quasi Biennial Oscillation ◽

Wind Profiles ◽

Fourier Model ◽

Trajectory Simulations

AbstractThe knowledge of weather conditions at the stratosphere is important for the planning and execution of high-altitude balloon flights, which require an accurate modeling of weather data over a period of time. Various methods based on statistical analysis, artificial neural networks, and cluster analysis have been employed to model the temporal variation of weather parameters. In the present study, a proper orthogonal decomposition (POD) method has been used to study the spatial as well as temporal variations of wind data in Singapore. The use of POD facilitates a compact representation of the weather dataset and aids in faster computation of wind profiles for use in balloon trajectory simulation. Further, the results reveal the existence of the quasi-biennial oscillation phenomenon, which is characteristic of equatorial easterly–westerly winds. This phenomenon enables the development of a Fourier prediction model, which can be used in real-time balloon trajectory simulations. The Fourier model is observed to be sensitive to wind velocity fluctuations, especially in the vicinity of alternating wind directions. However, it provides a reasonable projection of balloon trajectory, which can be used in preliminary planning and testing of high-altitude flights. Thus, a prior knowledge of wind profiles based on POD or a Fourier model aids in balloon station keeping. A simple case of altitude-controlled balloon flight is presented, and the results highlight the advantages of the present method in balloon station keeping.

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Limited success of the non-indigenous bivalve clam Rangia cuneata in the Lithuanian coastal waters of the Baltic Sea and the Curonian Lagoon

Oceanologia ◽

10.1016/j.oceano.2019.01.005 ◽

2019 ◽

Vol 61 (3) ◽

pp. 341-349 ◽

Cited By ~ 3

Author(s):

Sabina Solovjova ◽

Aurelija Samuilovienė ◽

Greta Srėbalienė ◽

Dan Minchin ◽

Sergej Olenin

Keyword(s):

Baltic Sea ◽

Coastal Waters ◽

Curonian Lagoon ◽

The Baltic Sea ◽

Rangia Cuneata ◽

Limited Success ◽

The Baltic

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Remote Sensing of Ice Phenology and Dynamics of Europe’s Largest Coastal Lagoon (The Curonian Lagoon)

Remote Sensing ◽

10.3390/rs11172059 ◽

2019 ◽

Vol 11 (17) ◽

pp. 2059 ◽

Cited By ~ 6

Author(s):

Rasa Idzelytė ◽

Igor E. Kozlov ◽

Georg Umgiesser

Keyword(s):

Baltic Sea ◽

Air Temperature ◽

Coastal Lagoon ◽

Ice Cover ◽

Satellite Observations ◽

Eastern Coast ◽

Curonian Lagoon ◽

Envisat Asar ◽

Ice Melt ◽

The North

A first-ever spatially detailed record of ice cover conditions in the Curonian Lagoon (CL), Europe’s largest coastal lagoon located in the southeastern Baltic Sea, is presented. The multi-mission synthetic aperture radar (SAR) measurements acquired in 2002–2017 by Envisat ASAR, RADARSAT-2, Sentinel-1 A/B, and supplemented by the cloud-free moderate imaging spectroradiometer (MODIS) data, are used to document the ice cover properties in the CL. As shown, satellite observations reveal a better performance over in situ records in defining the key stages of ice formation and decay in the CL. Using advantages of both data sources, an updated ice season duration (ISD) record is obtained to adequately describe the ice cover season in the CL. High-resolution ISD maps provide important spatial details of ice growth and decay in the CL. As found, ice cover resides longest in the south-eastern CL and along the eastern coast, including the Nemunas Delta, while the shortest ice season is observed in the northern CL. During the melting season, the ice melt pattern is clearly shaped by the direction of prevailing winds, and ice drift velocities obtained from a limited number of observations range within 0.03–0.14 m/s. The pronounced shortening of the ice season duration in the CL is observed at a rate of 1.6–2.3 days year‒1 during 2002–2017, which is much higher than reported for the nearby Baltic Sea regions. While the timing of the freeze onset and full freezing has not changed much, the dates of the final melt onset and last observation of ice have a clear decreasing pattern toward an earlier ice break-up and complete melt-off due to an increase of air temperature strongly linked to the North Atlantic Oscillation (NAO). Notably, the correlation between the ISD, air temperature, and winter NAO index is substantially higher when considering the lagoon-averaged ISD values derived from satellite observations compared to those derived from coastal records. The latter clearly demonstrated the richness of the satellite observations that should definitely be exploited in regional ice monitoring programs.

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