Very high-resolution modelling of submesoscale turbulent patterns and processes in the Baltic Sea

Abstract. In order to simulate submesoscale turbulent patterns and processes (STPPs) and to analyse their properties and dynamics, the Regional Ocean Modeling System (ROMS) was run for June 2016 in a subregion of the Baltic Sea. To create a realistic mesoscale environment, ROMS with 500 m horizontal resolution (referred to as R500) is one-way nested into an existing operational model, and STPPs with horizontal scales <1 km are resolved with a second nest of 100 m resolution (R100). Both nests use 10 terrain-following layers in the vertical. The comparison of the R500 results with a satellite image shows fair agreement. While R500 is driven by realistic air–sea fluxes, the atmospheric forcing is turned off in R100 because it prevents the generation of STPPs and blurs submesoscale structures. Therefore, R100 provides deep insight into ageostrophic processes and associated quantities under quasi-adiabatic conditions that are approximately met in no-wind or light-wind situations. The validity of the results is furthermore limited to the selected region and the time of the year. STPPs evolve rapidly within a about a day. They are characterized by vertical speeds of 𝒪(10) m d−1 and relative vorticities and divergences reaching multiples of the Coriolis parameter. Typical elements of the secondary circulation of two-dimensional strain-induced frontogenesis are identified at an exemplary front in shallow water, and details of the ageostrophic flow field are revealed. The conditions for inertial and symmetric instability are evaluated for the whole domain, and the components of the tendency equation are computed in a subregion. While anticyclonic eddies are generated solely along coasts, cyclonic eddies are rolled-up streamers and found in the entire domain. A special feature of the cyclones is their ability to absorb internal waves and to sustain patches of continuous upwelling for several days, favouring plankton growth. The kinematic properties show good agreement with observations, while some observed details within a small cyclonic eddy are only partly reproduced, most likely due to a lack of horizontal resolution or nonhydrostatic effects.

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An Evaluation and Implementation of the Regional Coupled Ice-Ocean Model of the Baltic Sea

10.5194/esd-2017-35 ◽

2017 ◽

Author(s):

Jaromir Jakacki ◽

Sebastian Meler

Keyword(s):

Baltic Sea ◽

Three Dimensional ◽

Coupled Model ◽

Horizontal Resolution ◽

Ocean Model ◽

System Model ◽

The Baltic Sea ◽

Community Earth System Model ◽

The Baltic ◽

Ice Model

Abstract. A three dimensional, regional coupled ice-ocean model based on the open-source Community Earth System Model has been developed and implemented for the Baltic Sea. The model consists of 66 vertical levels and has a horizontal resolution of approx. 2.3 km. The paper focuses on sea ice component results but the main changes have been introduced in the ocean part of the coupled model. The hydrodynamic part, being one of the most important components, has been also presented and validated. The ice model results were validated against the radar and satellite data, and the method of validation based on probability was introduced. In the last two decades satellite and model results show an increase in the ice extent over the whole Baltic Sea, which is an evidence of a negative trend in air temperature in recent decades and increasing of winter discharge from the catchment area.

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Nemo-Nordic 2.0: Updated Baltic Sea model based on NEMO 4.0

10.5194/egusphere-egu21-8728 ◽

2021 ◽

Author(s):

Tuomas Kärnä ◽

Ida Ringgaard ◽

Vasily Korabel ◽

Adam Nord ◽

Patrik Ljungemyr ◽

...

Keyword(s):

Baltic Sea ◽

Horizontal Resolution ◽

Sea Surface ◽

Small Scale ◽

The Baltic Sea ◽

Inflow Event ◽

Arkona Basin ◽

The Baltic ◽

Marine Environment Monitoring ◽

Monitoring Service

<p>We present Nemo-Nordic 2.0, the latest version of the operational marine forecasting model for the Baltic Sea used and developed in the Baltic Monitoring Forecasting Centre (BAL MFC) under the Copernicus Marine Environment Monitoring Service (CMEMS). The most notable differences between Nemo-Nordic 2.0 and its predecessor Nemo-Nordic 1.0 are the switch from NEMO 3.6 to NEMO 4.0 and an increase in horizontal resolution from 2 to 1 nautical mile. In addition, the model's bathymetry and bottom friction formulation have been updated. The model configuration was specially tuned to represent Major Baltic Inflow events. Focusing on a 2-year validation period from October 1, 2014, covering one Major Baltic Inflow event, Nemo-Nordic 2.0 simulates Sea Surface Height (SSH) well: centralized Root-Mean-Square Deviation (CRMSD) is within 10 cm for most stations outside the Inner Danish Waters. CRMSD is higher at some stations where small-scale topographical features cannot be correctly resolved. SSH variability tends to be overestimated in the Baltic Sea and underestimated in the Inner Danish Waters. Nemo-Nordic 2.0 represents Sea Surface Temperature (SST) and Salinity (SSS) well, although there is a negative bias around -0.5&#176;C in SST. The 2014 Major Baltic Inflow event is well reproduced. The simulated salt pulse agrees well with observations in the Arkona basin and progresses into the Gotland basin in 3 to 4 months.</p>

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DEVELOPMENT OF A NEMO BASED OPERATIONAL SYSTEM FOR THE GULF OF FINLAND AND THE KALININGRAD SHELF

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

10.21610/conferencearticle_58cb90a34d5c8 ◽

2017 ◽

Author(s):

Roman Vankevich ◽

Mikhail Molchanov ◽

Ekaterina Sofina ◽

...

Keyword(s):

Baltic Sea ◽

Mathematical Formulation ◽

Ocean Modeling ◽

Gulf Of Finland ◽

The Baltic Sea ◽

Effective Response ◽

Operational System ◽

Matter Transport ◽

The Baltic ◽

The Gulf Of Finland

This study is aimed at developing of an operational oceanographic system for the Russian sector in the Gulf of Finland and South-Eastern part of the Baltic Sea for operational forecast of hydrodynamic and ecosystem parameters on the basis of high and ultra-high spatial resolution models. The system is presented as a complex of regional and local models; for which a coupled modeling integration at boundary conditions exchange is fulfilled. The models share common mathematical formulation of general motion equations and a unified realization on the basis of programme code modeling modules designed for the ocean modeling – NEMO. The regional model of the Baltic Sea circulation is complemented by a module for the inert matter transport simulation. The latter is set up on the basis of a matter turbulent diffusion model with the use of two consistent equation systems: deterministic and stochastic. The designed operational system consists of two subsystems: operational oceanographic system of the coastal areas of the Baltic Sea and an expert-analytical system of operational monitoring of the aquatic environment and effective response to accidents at sea.

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Comparisons of Satellite and Modeled Surface Temperature and Chlorophyll Concentrations in the Baltic Sea with In Situ Data

Remote Sensing ◽

10.3390/rs13153049 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3049

Author(s):

Malgorzata Stramska ◽

Marta Konik ◽

Paulina Aniskiewicz ◽

Jaromir Jakacki ◽

Miroslaw Darecki

Keyword(s):

Baltic Sea ◽

Satellite Data ◽

In Situ Measurements ◽

Data Sets ◽

The Baltic Sea ◽

Data Set ◽

In Situ Data ◽

The Baltic ◽

Good Agreement

Among the most frequently used satellite data are surface chlorophyll concentration (Chl) and temperature (SST). These data can be degraded in some coastal areas, for example, in the Baltic Sea. Other popular sources of data are reanalysis models. Before satellite or model data can be used effectively, they should be extensively compared with in situ measurements. Herein, we present results of such comparisons. We used SST and Chl from model reanalysis and satellites, and in situ data measured at eight open Baltic Sea stations. The data cover time interval from 1 January 1998 to 31 December 2019, but some satellite data were not always available. Both the model and the satellite SST data had good agreement with in situ measurements. In contrast, satellite and model estimates of Chl concentrations presented large errors. Modeled Chl presented the lowest bias and the best correlation with in situ data from all Chl data sets evaluated. Chl estimates from a regionally tuned algorithm (SatBaltic) had smaller errors in comparison with other satellite data sets and good agreement with in situ data in summer. Statistics were not as good for the full data set. High uncertainties found in chlorophyll satellite algorithms for the Baltic Sea highlight the importance of continuous regional validation of such algorithms with in situ data.

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DEVELOPMENT OF A NEMO BASED OPERATIONAL SYSTEM FOR THE GULF OF FINLAND AND THE KALININGRAD SHELF

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

10.31519/conferencearticle_5b1b93cbe18747.49034561 ◽

2017 ◽

Author(s):

Roman Vankevich ◽

Ekaterina Sofina ◽

Tatjana Eremina ◽

...

Keyword(s):

Baltic Sea ◽

Mathematical Formulation ◽

Ocean Modeling ◽

Gulf Of Finland ◽

The Baltic Sea ◽

Effective Response ◽

Operational System ◽

Matter Transport ◽

The Baltic ◽

The Gulf Of Finland

This study is aimed at developing of an operational oceanographic system for the Russian sector in the Gulf of Finland and South-Eastern part of the Baltic Sea for operational forecast of hydrodynamic and ecosystem parameters on the basis of high and ultra-high spatial resolution models. The system is presented as a complex of regional and local models; for which a coupled modeling integration at boundary conditions exchange is fulfilled. The models share common mathematical formulation of general motion equations and a unified realization on the basis of programme code modeling modules designed for the ocean modeling – NEMO. The regional model of the Baltic Sea circulation is complemented by a module for the inert matter transport simulation. The latter is set up on the basis of a matter turbulent diffusion model with the use of two consistent equation systems: deterministic and stochastic. The designed operational system consists of two subsystems: operational oceanographic system of the coastal areas of the Baltic Sea and an expert-analytical system of operational monitoring of the aquatic environment and effective response to accidents at sea.

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DEVELOPMENT OF A NEMO BASED OPERATIONAL SYSTEM FOR THE GULF OF FINLAND AND THE KALININGRAD SHELF

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

10.31519/conferencearticle_5b1b93f0b46083.45377437 ◽

2017 ◽

Author(s):

Roman Vankevich ◽

Mikhail Molchanov ◽

Ekaterina Sofina ◽

...

Keyword(s):

Baltic Sea ◽

Mathematical Formulation ◽

Ocean Modeling ◽

Gulf Of Finland ◽

The Baltic Sea ◽

Effective Response ◽

Operational System ◽

Matter Transport ◽

The Baltic ◽

The Gulf Of Finland

This study is aimed at developing of an operational oceanographic system for the Russian sector in the Gulf of Finland and South-Eastern part of the Baltic Sea for operational forecast of hydrodynamic and ecosystem parameters on the basis of high and ultra-high spatial resolution models. The system is presented as a complex of regional and local models; for which a coupled modeling integration at boundary conditions exchange is fulfilled. The models share common mathematical formulation of general motion equations and a unified realization on the basis of programme code modeling modules designed for the ocean modeling – NEMO. The regional model of the Baltic Sea circulation is complemented by a module for the inert matter transport simulation. The latter is set up on the basis of a matter turbulent diffusion model with the use of two consistent equation systems: deterministic and stochastic. The designed operational system consists of two subsystems: operational oceanographic system of the coastal areas of the Baltic Sea and an expert-analytical system of operational monitoring of the aquatic environment and effective response to accidents at sea.

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A comparison between the ERA40 and the SMHI gridded meteorological databases as applied to Baltic Sea modelling

Hydrology Research ◽

10.2166/nh.2005.0028 ◽

2005 ◽

Vol 36 (4-5) ◽

pp. 369-380 ◽

Cited By ~ 21

Author(s):

A. Omstedt ◽

Y. Chen ◽

K. Wesslander

Keyword(s):

Baltic Sea ◽

Time Resolution ◽

Meteorological Data ◽

Horizontal Resolution ◽

Data Sets ◽

The Baltic Sea ◽

Data Set ◽

Original Surface ◽

Baltic Sea Region ◽

The Baltic

Two gridded meteorological data sets for the Baltic Sea region, both having 1°×1° horizontal resolution, were compared and analysed for use in Baltic Sea modelling. The SMHI 1°×1° data set covers surface parameters with a three-hour time resolution over the 1970–2004 period. The ERA40 data cover analysed and modelled parameters for several atmospheric layers with a six-hour time resolution over the 1957–2002 period. Meteorological variables considered in this analysis were air temperature, wind speed, total cloud cover, relative humidity and precipitation. In considering Baltic Sea modelling, we examined maximum ice extent, water temperature, salinity and net precipitation calculations. The two data sets are largely similar and can both be used in Baltic Sea modelling. However, their horizontal resolution is too coarse for resolving marine conditions over the Baltic Sea. This implies, for example, that the ERA40 original surface winds are too low for some Baltic Sea regions. The ERA40 precipitation values are also too low compared with those of the SMHI and other available data.

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Temporal and spatial sedimentation rate variabilities in the eastern Gotland Basin, the Baltic Sea

Boreas ◽

10.1080/03009480210645 ◽

2002 ◽

Vol 31 (1) ◽

pp. 65-74 ◽

Cited By ~ 12

Author(s):

Christian Christiansen ◽

Helmar Kunzendorf ◽

Kay-Christian Emeis ◽

Rudolf Endler ◽

Ulrich Struck ◽

...

Keyword(s):

Baltic Sea ◽

Sedimentation Rate ◽

The Baltic Sea ◽

Gotland Basin ◽

Temporal And Spatial ◽

The Baltic

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Russian Oil: Production and Exports

Voprosy Ekonomiki ◽

10.32609/0042-8736-2003-9-136-146 ◽

2003 ◽

pp. 136-146

Author(s):

K. Liuhto

Keyword(s):

Baltic Sea ◽

Statistical Data ◽

Oil Production ◽

The Baltic Sea ◽

North West ◽

The North ◽

Oil Transportation ◽

Sea Ports ◽

The Baltic

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.

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