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Tytuł:
eBalticGrid – an interactive platform for the visualisation of results from a high-resolution operational Baltic Sea model
Autorzy:
Jakacki, J.
Przyborska, A.
Nowicki, A.
Wichorowski, M.
Przyborski, M.
Białoskórski, M.
Sochacki, C.
Tylman, R.
Powiązania:
https://bibliotekanauki.pl/articles/108447.pdf
Data publikacji:
2017
Wydawca:
Instytut Meteorologii i Gospodarki Wodnej - Państwowy Instytut Badawczy
Tematy:
multimodelling
Baltic Sea
forecasting
hydrodynamic model
ice model
Opis:
In recent years, modelling has been one of the fastest growing fields of science. Ocean, ice and atmospheric models have become a powerful tool that has supported many scientific fields during the last few decades. Our work presents the new operational service – called eBalticGrid – implemented into the PLGrid Infrastructure (Dziekoński et al. 2014). The grid is based on three modelling tools – an ocean model (Parallel Ocean Program), an ice model (Community Ice Code) and an atmospheric model (Whether Research and Forecasting Model). The service provides access to 72-hour forecasts for the Baltic Sea area. It includes the physical state of the Baltic Sea, its ice cover and the main atmospheric fields, which are the key drivers of the Baltic’s physical state. Unlike other services, this provides the additional three-dimensional fields of temperature, salinity and currents in the Baltic Sea. The models work in operational mode and currently one simulation per day is run. The service has been implemented mostly for researchers. Access to the results does not require any modelling knowledge. Therefore, the main interface between a user and the model results was designed as a portal providing easy access to the model’s output. It will also be a very suitable tool for teaching students about the hydrology of the Baltic Sea. Data from the system are delivered to another operational system – SatBaltic (Woźniak et al. 2011). The development of an output format to be suitable for navigational software (GRIB files) and sharing via FTP is also planned.
Źródło:
Meteorology Hydrology and Water Management. Research and Operational Applications; 2017, 5, 2; 13-20
2299-3835
2353-5652
Pojawia się w:
Meteorology Hydrology and Water Management. Research and Operational Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A model-measurements comparison of atmospheric forcing and surface fluxes of the Baltic Sea
Autorzy:
Rudolph, C.
Lehmann, A.
Powiązania:
https://bibliotekanauki.pl/articles/48268.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
coupled sea-ice-ocean model
surface flux
temperature
pressure
radiation flux
heat flux
air-sea interaction
Baltic Sea
wave radiation
Opis:
Observed basic meteorological quantities, heat and radiation fluxes from three different measurement stations in the Baltic Sea are compared with model data of the coupled sea-ice-ocean model BSIOM in order to evaluate the atmospheric forcing, corresponding surface fluxes and the sea surface response. Observational data weremade available from the BASIS winter campaigns in 1998 and 2001 as well as from the r/v ‘Alkor’ cruise in June 2001. Simulated fluxes were calculated from prescribed atmospheric forcing provided from the SMHI meteorological database and modelled sea surface temperatures. The comparison of these fluxes with observations demonstrates a strong correlation, even though mean differences in sensible heat fluxes range from 4 to 12 W m−2 in winter and −25 W m−2 in the June experiment. Differences in latent heat fluxes range from −10 to 23 W m−2. The short-wave radiation flux used as model forcing is on average 15 W m−2 less than the corresponding observations for the winter experiments and 40 W m−2 for the June experiment. Differences in net long-wave radiation fluxes range from −5 to 12W m−2 in winter and −62W m−2 for the June experiment. The correspondence between measured and calculated momentum fluxes is very high, which confirms the usability of our model component for calculating surface winds and wind stresses from the atmospheric surface pressure.
Źródło:
Oceanologia; 2006, 48, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Windshield Defrost Simplified CFD Model
Autorzy:
Schmid, Michal
Powiązania:
https://bibliotekanauki.pl/articles/112070.pdf
Data publikacji:
2019
Wydawca:
Stowarzyszenie Menedżerów Jakości i Produkcji
Tematy:
windshield defrost
CFD
ice layer thickness
VOF
Thin Film
model CFD
model VOF
cienki film
Opis:
The windshield defrost system, in general, is a vehicle safety feature. Thus, its restricted by variety of directives. However, the OMEs’ benchmark targets could be even more demanding as the deicing process is in addition also part of passengers comfort. From vehicle design point of view the wind-shield defrost system is typically connected to HVAC unit (Heating, Ventilation and Air Conditioning). In the technical solution the windshield is heated via hot air convection. Nevertheless, other methods are becoming more and more popular, like directly heated glass by hot wire ohmic heating (heated glasses). The defrost CFD model should predict the ice layer thickness in time and space and in environmental conditions defined according to appropriate directives and technical solution. The accurate and fast modelling technique is essential part of a vehicle development, especially nowadays, where the optimization techniques area widely used and requires hundreds of simulations runs. Modelling requests are even increasing with modern pure electric vehicles (EVs), were the thermal and energy management is more demanding compared to the classical internal combustion engine (ICE) vehicles. The aim of the work is to verify possibility to model the ice layer thickness with simplified approach, which could be beneficial from computational time burden.
Źródło:
Production Engineering Archives; 2019, 25; 8-11
2353-5156
2353-7779
Pojawia się w:
Production Engineering Archives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interaction of ships moving in opposing directions among ice floes
Autorzy:
Goncharov, V.
Klementieva, N.
Zueva, E.
Powiązania:
https://bibliotekanauki.pl/articles/135677.pdf
Data publikacji:
2015
Wydawca:
Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:
collision
computer simulation
ice floe
maneuvering
mathematical model
navigation
side force
yawing moment
Opis:
During winter in arctic seas, navigation of ships near ports occurs within ice channels created and maintained by icebreakers. Small ice floes fill the relatively narrow navigable channel, and ships are forced to produce the overtaking or opposing separation over short distances and under the action of ice floes. This paper presents an analytical model of the interaction of ships under the conditions just described as well as the results of a simulation. The simulation showed side force and yawing moments were dependent on ice conditions and the ship’s dimensions and motion characteristics.
Źródło:
Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2015, 43 (115); 91-98
1733-8670
2392-0378
Pojawia się w:
Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Odwzorowanie przepływu wód podziemnych systemu wodonośnego odcinka Kościan–Wolsztyn Pradoliny warszawsko-berlińskiej na modelach lokalnym i regionalnym
Reconstruction of groundwater flow in the water-bearing system of the Warsaw-Berlin Ice-Marginal Valley in the Kościan–Wolsztyn area based on local and regional models
Autorzy:
Dąbrowski, S.
Janiszewska, B.
Rynarzewski, W.
Straburzyńska-Janiszewska, R.
Powiązania:
https://bibliotekanauki.pl/articles/2061863.pdf
Data publikacji:
2018
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
model lokalny
model regionalny
bilanse systemu wodonośnego
Pradolina Warszawsko-Berlińska
local model
regional model
balance of water-bearing system
Warsaw-Berlin Ice-Marginal Valley
Opis:
W badaniach hydrogeologicznych dolin rzecznych i pradolin do oceny zasobów wód podziemnych stosuje się badania modelowe, realizowane w układach lokalnych (odwzorowane do 1 : 25 000) lub regionalnych (skale poniżej 1 : 50 000). Zwykle stanowią one odrębne podsystemy wodonośne ściśle związane z wodami powierzchniowymi i ascenzją wgłębnych poziomów wodonośnych (Przybyłek, Dąbrowski, 2013) i wymagają szczegółowego odwzorowania na modelach systemów zasilania i drenażu (Dąbrowski i in., 2011). W artykule przedstawiono i porównano wyniki badań modelowych odcinka Kościan–Wolsztyn Pradoliny Warszawsko-Berlińskiej na dwóch modelach układu krążenia w celu oceny zasobów dyspozycyjnych – modelu dwuwarstwowym w skali 1 : 25 000 zrealizowanym w 2003 r. przy użyciu programu z biblioteki Hydrylib i modelu regionalnym zlewni Obry z analizowanym odcinkiem pradoliny w układzie czterech warstw modelowych, wykonanym w 2017 r. przy użyciu programu Groundwater Vistas.
Hydrogeological research of river and ice-marginal valleys, which are conducted for groundwater resources assessment, involve modelling of local (map scale below 1 : 25 000) or regional (map scale below 1 : 50 000) systems. Usually, these systems are discrete water-bearing subsystems related to surface waters and ascent recharge from deep aquifers (Przybyłek, Dąbrowski, 2013), which require detailed reconstruction of recharge and drainage systems (Dąbrowski et al., 2011). This paper presents and compares the results of modelling research of the Warsaw-Berlin Ice-Marginal Valley in the Kościan–Wolsztyn area conducted on two circulation system models to estimate disposable resources. These are the local, two- aquifer model of the study area, developed using Hydrylib software in 2003, and the regional, four-aquifer model of the Obra catchment for the study area, created using Groundwater Vistas software in 2017.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2018, 471, Hydrogeologia, z. 15; 15--22
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Naprjazhenno deformirovannoe sostojanie ehlementov opornojj stojjki morskojj stal'nojj stacionarnojj platformy v zone kontakta so l'dom
Stress strain behavior of the supporting column elements of offshore steel fixed platform in the ice contact area
Autorzy:
Sincov, V.
Fursov, A.
Powiązania:
https://bibliotekanauki.pl/articles/76323.pdf
Data publikacji:
2013
Wydawca:
Komisja Motoryzacji i Energetyki Rolnictwa
Tematy:
behaviour
stress distribution
offshore platform
marine stationary platform
ice load
contact zone
design model
Opis:
In the freezing seas, offshore fixed platforms are at high loads at the ice contact zone, presented a variation of the design of jacket active protection from ice loads, and compared with the existing design of the platform, studied stress strain behavior of models in the software complex Lira. This comparison is the first to determine the optimum contact interaction, in which the design ice load will be minimal and will not lead to its destruction, and the opposition of the load will be possible to destroy the ice.
Źródło:
Motrol. Motoryzacja i Energetyka Rolnictwa; 2013, 15, 5
1730-8658
Pojawia się w:
Motrol. Motoryzacja i Energetyka Rolnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model zmian powierzchni lodów morskich Arktyki (1979-2013) – zmienne sterujące w modelu „minimalistycznym” i ich wymowa klimatyczna
Model of changes in the Arctic sea-ice extent (1979-2013) – variables steering the 'minimalist' model and their climatic significance
Autorzy:
Marsz, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/260796.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Klimatologów Polskich
Tematy:
Arktyka
lody morskie
zmiany powierzchni lodów
czynniki sterujące
model
cyrkulacja termohalinowa
cyrkulacja atmosferyczna
Arctic
sea ice
ice extent changes
steering variables
thermohaline circulation
atmospheric circulation
Opis:
Praca omawia model zmian powierzchni zlodzonej Arktyki typu „białej skrzynki”, opierający się na dwu zmiennych niezależnych – wskaźniku oznaczonym jako DG3L, który charakteryzuje intensywność cyrkulacji termohalinowej (THC) na Atlantyku Północnym i wskaźniku D, który charakteryzuje cyrkulację atmosferyczną nad Arktyką. Objaśnienie konstrukcji obu wskaźników i wartości ich szeregów czasowych przedstawione jest w załącznikach Z1 i Z2. Okres opracowania obejmuje lata 1979-2013 i jest limitowany dostępnością danych o zmianach powierzchni lodów morskich w Arktyce. Model liniowy opierający się na tych zmiennych objaśnia ~72% wariancji rocznej powierzchni zlodzonej w Arktyce i powyżej 65% wariancji powierzchni zlodzonej w marcu (maksimum rozwoju powierzchni lodów) i wrześniu (minimum). Główną rolę w kształtowaniu tej zmienności odgrywa zmienność cyrkulacji termohalinowej, rola cyrkulacji atmosferycznej jest niewielka i wykazuje silną zmienność sezonową. Analiza tego modelu wykazała, że rzeczywiste zależności są nieliniowe, a zmiany pokrywy lodowej zachodzą w dwu odrębnych reżimach – „ciepłym” i „chłodnym”. Reżim „ciepły” funkcjonuje w sytuacji, gdy THC jest bardziej intensywna niż przeciętnie (wskaźnik DG3L > 0). Dochodzi wtedy do szybkiego spadku powierzchni lodów w okresie ciepłym – zwłaszcza we wrześniu i powolnego spadku rozmiarów pokrywy lodowej w marcu, cyrkulacja atmosferyczna w tym reżimie odgrywa istotną rolę w kształtowaniu zmian powierzchni lodów. Spadek natężenia THC poniżej przeciętnej (DG3L ≤ 0), z opóźnieniem około 6.letnim prowadzi, do przejścia do reżimu „chodnego”. W reżimie chłodnym następuje szybki przyrost powierzchni lodów w okresie ciepłym i bardzo powolny wzrost powierzchni lodów w marcu, rola cyrkulacji atmosferycznej w kształtowaniu zmienności pokrywy lodowej staje się nikła. Po dalszych kilku latach utrzymywania się reżimu „chłodnego” międzyroczne zmiany powierzchni zlodzonej stają się małe. Analizy związków między zmiennymi z przesunięciami czasowymi wykazały, że cyrkulacja atmosferyczna nad Arktyką stanowi funkcję THC. W rezultacie, za główną przyczynę zmian powierzchni zlodzonej Arktyki należy uznać rozciągnięte w czasie działanie zmian intensywności THC, które w rozpatrywanym okresie objaśnia ~90% wariancji rocznej powierzchni zlodzonej.
The paper presents the assumptions and structure of statistical model reproducing the changes in sea ice extent in the Arctic, using the minimum number of steering variables. The data set of NASA's Goddard Space Flight Center (GSFC) nsidc0192_seaice_trends_climo/total-area-ice-extent/nasateam/ (Total Ice-Covered Area and Extent) was used as starting data in the calibration of this model. Its subsets characterizing the sea ice extent of the Arctic Ocean (ArctOcn), Greenland Sea (Grnland), Barents and Kara seas (BarKara) were used. Their sums create a new variable known as the ‘Proper Arctic’. This model also used the following subsets: Archipelago Canadian (CanArch), Bay and Strait Hudson (Hudson), and Baffin Bay and Labrador Sea (Baffin), the sum of which creates another variable the ‘American Arctic’. The sum of all the above mentioned subsets creates a variable defined as the ‘entire Arctic’. The study covered the period 1979-2013, for which the said data set is made up of uniform and reliable data based on satellite observations. The model was developed for moments of maximum (March) and minimum (September) development of sea ice extent as well as for the annual average sea ice extent. After presenting the assumptions of the model (model type ‘White box’), formal analysis of the type and characteristics of the model, the choice of steering variables (independent; Chapters 3 and 4) was made. The index characterizing the intensity of thermohaline circulation (THC) in the North Atlantic, referred to as DG3L and an index characterizing atmospheric circulation having significant influence on changes in sea ice extent, marked as D, were used as independent variables in this model. Physical fundamentals and rules for calculating the DG3L index are discussed in detail in Annex 1, and the D index in Annex 2. These Annexes also include time series of both indexes (DG3L – 1880-2015; D – 1949-2015). Research into delays between the impact of variables and changes in sea ice extent indicated that sea ice extent showed maximum strength of the correlation with the DG3L variable with a three-year delay and with D variable with zero delay. The final form of the model is a simple equation of multiple regression (equation [1]). The following equations are used for estimating the regression parameters for individual sea areas in those time series: the Proper Arctic – equation [1a, 1b, 1c]; the American Arctic – equations [2a, 2b, 2c] and for the entire Arctic - equation [3a, 3b, 3c]. Statistical characteristics of each model are presented in Tables 3, 4 and 5, and Figures 2, 3 and 4 respectively and show the scattering of values estimated by means of each model in relation to the observed values. All models show high statistical significance. The best results, both in terms of explanation of the variance of the observed sea ice extent, as well as the size of the standard errors of estimation of sea ice extent are obtained for changes in the sea ice extent of the entire Arctic. The reasons for this may be traced back to the fact that errors in the estimation of partial models ([1a, 1b, 1c] and [2a, 2b, 2c]) have different signs, which in a synthetic model partially cancel out each other. Moreover, if the variable DG3L three years before shows strong and evenly distributed in time action, the D variable characterizing atmospheric circulation shows clearly seasonal activity – it is marked only during the minimum development of sea ice extent (September), when the degree of ice concentration is reduced, allowing its relatively free drift. The model for the annual average of sea ice extent of the entire Arctic (in the accepted limits) explains 71.5% of the variance, in September 68%, and in March 65% of the variance (Table 5). The lowest values are obtained for the American Arctic, where the D variable, characterizing atmospheric circulation does not appear to have significant influence, so the model is a linear equation with one variable (DG3L). Nevertheless, also in this case, the variance of the annual sea ice extent in the American Arctic is explained exceeding 50%. Variability of THC (described by the DG3L index) explains ~67% of the variance of annual sea ice extent and variability of atmospheric circulation (described by the D index) explains ~6% of the variance of annual sea ice extent of the entire Arctic. It allows claiming that THC and atmospheric circulation are the essential factors that influence the variability of sea ice extent of the Arctic. Both of these factors are natural factors. Further analysis of the results presented by various models and especially those affected by the DG3L variable (Fig. 5) delayed by three years suggests that the linear model is not the most appropriate model reflecting the changes in the sea ice extent of the entire Arctic and its parts. The action of DG3L variable, accumulated over several years, is saved and this causes that a strong significant correlation with the sea ice extent is prolonged. The analysis carried out by means of the segmented regression showed that the variability of sea ice extent was different where THC is lower than the average (DG3L ≤ 0), or different where THC is stronger than average (DG3L> 0; see equation [4a, 4b]). When the index is zero or less than zero, the impact of THC on the increase in sea ice extent is limited and the influence of changes in atmospheric circulation on sea ice extent is very small. Conversely, when the THC becomes intense and imports increased amounts of heat to the Arctic, the influence of DG3L index on the decrease in sea ice extent rises, like growing impact of atmospheric circulation on variation of sea ice extent (see equations [5a, 5b]. The segmented regression equations with these two variables explain 88.76% of the observed annual variation of sea ice extent of the entire Arctic (equations [5a, 5b]).This means that the sea ice extent of the Arctic is variable in two distinct regimes – ‘warm’, when the DG3L> 0 and ‘cold’, when the DG3L ≤ 0. This is similar to the results of Proshutinsky and Johnson (1997), Polyakov et al. (1999) and Polyakov and Johnson (2000) and their LFO oscillation. Time limits of the transition intensity of the THC phases from the positive to negative and vice versa correspond to similar limits of LFO, suggesting that the two different systems have the same cause. Polyakov and Johnson (2000) and Polyakov et al. (2002, 2003, 2004, 2005) can see the main reason for the change in the LFO regime in the transition of atmospheric circulation from anticyclonic regime to cyclonic regime and vice versa. The analysis of the reason for the transition of regime of changes in sea ice extent from ‘warm’ to ‘cold’ and vice versa – THC or atmospheric circulation – has shown that the D index is a function of previous changes in DG3L index. Atmospheric circulation over the Arctic shows a greater delay in response to changes in THC than the sea ice extent – this occurs with a 6-year delay (see Table 6, Equation 6). This allows replacing the D variable in the equations describing the change in sea ice extent, directly by DG3L variable from 6 years before (see Equation [7a, 7b]).These simultaneous equations explain about 90% of the observed annual variance of the sea ice extent of the entire Arctic in the years 1979-2013. Most importantly, however, it can be stated, with a high degree of certainty, that the variability of THC of the North Atlantic steers both the changes in sea ice extent and Basic features of atmospheric circulation over the Arctic. The effects of other factors than THC, having influence on variability of sea ice extent and the basic processes of the climate in the Arctic, in the short time scales, leave not too much space/place. The transition from ‘cold’ to ‘warm’ regime in the development of the sea ice extent in the Arctic requires an increase in the intensity of THC. If the values of DG3L index are greater than 0 for a period not shorter than three years, the decrease in the sea ice extent will start, initially in the period of its minimum development (August, September). If the resultant values of the DG3L index have positive values for further three years, the atmospheric circulation will transform into a cyclonic circulation (D index goes to positive values). The role of atmospheric circulation during the ‘warm’ season in the Arctic having influence on the change (reduction) of the sea ice extent becomes significant. The ‘warm’ regime will remain as long as long after its start the situation in which the algebraic sum of DG3L values is greater than 0. If such a situation lasts long, or in case of accumulation of high values of DG3L index, the sea ice cover can disappear almost completely in the warm period. The transition from the ‘warm’ regime to the ‘cold’ regime demands fulfillment of reverse conditions – a consistent decrease in the values of DG3L index into negative values for at least another three year period. After three years this will result in rapid increase in sea ice extent during warm period, thereby increasing the annual average of sea ice extent. If in subsequent years the value of DG3L index remains lower than zero, after the next 3-4 years, the atmospheric circulation will become the anticyclonic circulation. After that there will be gradual, slow growth in sea ice extent, decrease in air temperature, increase in ice thickness and change in the age of the ice structure towards the increase in the multi-year ice. The ice cover in the Arctic will become "self-sustaining", reducing interannual variability. Major changes will occur in the ‘warm’ season, minor in other seasons. The maximum sea ice extent of the Arctic in the cold season, with current conditions in the ‘cold’ regime, can reach ~13.5-14.5 million km2, the average annual sea ice extent should be ~12 (± 0.5) million km2. This area, especially in the winter season, may be in fact higher, since the weakening of the THC must also lead to a decrease in air temperature in the hemisphere.
Źródło:
Problemy Klimatologii Polarnej; 2015, 25; s. 249-334
1234-0715
Pojawia się w:
Problemy Klimatologii Polarnej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New coupled atmosphere-ocean-ice system COSMO-CLM/NEMO: assessing air temperature sensitivity over the North and Baltic Seas
Autorzy:
Van Pham, T.
Brauch, J.
Dieterich, C.
Frueh, B.
Ahrens, B.
Powiązania:
https://bibliotekanauki.pl/articles/48930.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
coupled atmosphere-ocean-ice system
temperature sensitivity
air temperature
Baltic Sea
North Sea
regional climate modelling
COSMO-CLM model
Źródło:
Oceanologia; 2014, 56, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability of vessels in an ice-free Arctic
Autorzy:
Johansen, K.
Sollid, M. P.
Gudmestad, O. T.
Powiązania:
https://bibliotekanauki.pl/articles/1841599.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Ice-Free Arctic
Maritime Education and Training
stability of vessels
ship stability
Icing
marine Icing model
Polar Low
IMO Polar Code
Opis:
One consequence of the declining ice cover in the Arctic is increased areas of open seas. These new open sea areas lead to some challenging aspects related to ship stability. Longer fetch lengths, associated with build-up of larger waves followed by increased conditions for sea spray icing on vessels is one aspect. Open seas in combination with cold atmospheric temperatures is a prerequisite for polar low pressures to occur. Polar lows may represent an additional aspect of increased icing on vessels by heavy snow in addition to extensive sea spray ice accretion. Over the last decades, different formulas for prediction of sea spray ice accretion rate on ships were developed to form basis for ice accretion warnings. Some of these formulas seem to have certain limitations and appear to be conservative. Important limitations of some formulas are considerations regarding heat flux, relationship between wind and waves, and ice accretion related to Polar lows. This paper will take a closer look at the accuracy and the realism of different ice accretion formulas and, related to this aspect, we will also discuss whether ship officer candidates receive sufficient maritime education and training (MET) related to realistic ice accretion and ship icing aspects.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 3; 663-671
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quality assessment of atmospheric surface fields over the Baltic Sea from an ensemble of regional climate model simulations with respect to ocean dynamics
Autorzy:
Meier, H.E.M.
Hoglund, A.
Doscher, R.
Andersson, H.
Loptien, U.
Kjellstrom, E.
Powiązania:
https://bibliotekanauki.pl/articles/48250.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
atmosphere-ocean coupling
Baltic region
climate change
climate model
ecosystem
global warming
hydrographic change
regional climate
regional climate modelling
sea ice
temperature
water temperature
Opis:
Climate model results for the Baltic Sea region from an ensemble of eight simulations using the Rossby Centre Atmosphere model version 3 (RCA3) driven with lateral boundary data from global climate models (GCMs) are compared with results from a downscaled ERA40 simulation and gridded observations from 1980 –2006. The results showed that data from RCA3 scenario simulations should not be used as forcing for Baltic Sea models in climate change impact studies because biases of the control climate significantly affect the simulated changes of future projections. For instance, biases of the sea ice cover in RCA3 in the present climate affect the sensitivity of the model’s response to changing climate due to the ice-albedo feedback. From the large ensemble of available RCA3 scenario simulations two GCMs with good performance in downscaling experiments during the control period 1980–2006 were selected. In this study, only the quality of atmospheric surface fields over the Baltic Sea was chosen as a selection criterion. For the greenhouse gas emission scenario A1B two transient simulations for 1961 –2100 driven by these two GCMs were performed using the regional, fully coupled atmosphere-ice-ocean model RCAO. It was shown that RCAO has the potential to improve the results in downscaling experiments driven by GCMs considerably, because sea surface temperatures and sea ice concentrations are calculated more realistically with RCAO than when RCA3 has been forced with surface boundary data from GCMs. For instance, the seasonal 2 m air temperature cycle is closer to observations in RCAO than in RCA3 downscaling simulations. However, the parameterizations of air-sea fluxes in RCAO need to be improved.
Źródło:
Oceanologia; 2011, 53, (1-TI)
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-10 z 10

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