Annual and seasonal trend detection of significant wave height, energy period and wave power in the Mediterranean Sea

Abstract. This study analyzes the link between the SWH (Significant Wave Height) distribution in the Mediterranean Sea during the second half of the 20th century and the Northern Hemisphere SLP (Sea Level Pressure) teleconnection patterns. The SWH distribution is computed using the WAM (WAve Model) forced by the surface wind fields provided by the ERA-40 reanalysis for the period 1958–2001. The time series of mid-latitude teleconnection patterns are downloaded from the NOAA web site. This study shows that several mid-latitude patterns are linked to the SWH field in the Mediterranean, especially in its western part during the cold season: East Atlantic Pattern (EA), Scandinavian Pattern (SCA), North Atlantic Oscillation (NAO), East Atlantic/West Russia Pattern (EA/WR) and East Pacific/ North Pacific Pattern (EP/NP). Though the East Atlantic pattern exerts the largest influence, it is not sufficient to characterize the dominant variability. NAO, though relevant, has an effect smaller than EA and comparable to other patterns. Some link results from possibly spurious structures. Patterns which have a very different global structure are associated to similar spatial features of the wave variability in the Mediterranean Sea. These two problems are, admittedly, shortcomings of this analysis, which shows the complexity of the response of the Mediterranean SWH to global scale SLP teleconnection patterns.

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Trends and variability of ocean waves under RCP8.5 emission scenario in the Mediterranean Sea

Ocean Dynamics ◽

10.1007/s10236-020-01419-8 ◽

2020 ◽

Vol 71 (1) ◽

pp. 97-117 ◽

Cited By ~ 2

Author(s):

Francesco De Leo ◽

Giovanni Besio ◽

Lorenzo Mentaschi

Keyword(s):

Mediterranean Sea ◽

Wave Height ◽

Significant Wave Height ◽

Emission Scenario ◽

Ocean Waves ◽

Wave Climate ◽

Gas Production ◽

Mitigation Measures ◽

Significant Wave ◽

The Mediterranean

AbstractWind-generated ocean waves are key inputs for several studies and applications, both near the coast (coastal vulnerability assessment, coastal structures design, harbor operativity) and off-shore (a.o. oil and gas production, ship routes, and navigation safety). As such, the evaluation of trends in future wave climate is fundamental for the development of efficient policies in the framework of climate change adaptation and mitigation measures. This study focuses on the Mediterranean Sea, an area of primary interest, since it plays a crucial role in the worldwide maritime transport and it is highly populated along all its coasts. We perform an analysis of wave climate changes using an ensemble of 7 models under emission scenario RCP8.5, over the entire Mediterranean basin. Future projections of wave climate and their variability are analyzed taking into account annual statistics of wave parameters, such as significant wave height, mean period, and mean direction. The results show, on average, a decreasing trend of significant wave height and mean period, while the wave directions may be characterized by a slight eastward shift.

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Wave Energy Assessment in the Bohai Sea and the Yellow Sea Based on a 40-Year Hindcast

Water ◽

10.3390/w12082087 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2087

Author(s):

Jie Dong ◽

Jian Shi ◽

Jianchun Zhao ◽

Chi Zhang ◽

Haiyan Xu

Keyword(s):

Wave Height ◽

Wave Energy ◽

Yellow Sea ◽

Significant Wave Height ◽

Bohai Sea ◽

The Yellow Sea ◽

Wave Power ◽

Power Flux ◽

Significant Wave ◽

The Bohai Sea

A wave hindcast, covering the period of 1979–2018, was preformed to assess wave energy potential in the Bohai Sea and the Yellow Sea. The hindcase was carried out using the third generation wave model TOMAWAC with high spatio-temporal resolution (about 1 km and on an hourly basis). Results show that the mean values of significant wave height increase from north to south, and the maximum values are located at the south part of the Yellow Sea with amplitude within 1.6 m. The magnitudes of significant wave height values vary significantly within seasons; they are at a maximum in winter. The wave energy potential was represented by distributions of the wave power flux. The largest values appear in the southeast part of the numerical domain with wave power flux values of 8 kW/m. The wave power flux values are less than 2 kW/m in the Bohai Sea and nearshore areas of the Yellow Sea. The seasonal mean wave power flux was found up to 8 kW/m in the winter and autumn. To investigate the exploitable wave energy, a wave energy event was defined based on the significant wave height (Hs) threshold values of 0.5 m. The wave energy in south part of the Yellow Sea is more steady and intensive than in the other areas. Wave energy in winter is more suitable for harvesting wave energy. Long-term trends of wave power availability suggest that the values of wave power slightly decreased in the 1990s, whereas they have been increasing since 2006.

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Changes of Significant Wave Height, Energy Period and Wave Power in Italy in the Period 1979–2018

Environmental Sciences Proceedings ◽

10.3390/environsciproc2020002003 ◽

2020 ◽

Vol 2 (1) ◽

pp. 3

Author(s):

Tommaso Caloiero ◽

Francesco Aristodemo ◽

Danilo Algieri Ferraro

Keyword(s):

Time Series ◽

Wave Height ◽

Significant Wave Height ◽

Kendall Test ◽

Wave Power ◽

Mean Values ◽

Significant Wave ◽

Wave Energy Converters ◽

Long Wave ◽

Significance Levels

An analysis of a 40-year long wave time series was performed, along the coasts of Italy, in order to identify ongoing trends of two synthetic parameters, significant wave height (Hs) and energy period (Te), and of the wave power (P). First, wave data were deduced from the global atmospheric reanalysis ERA-INTERIM by the ECMWF and checked to verify their consistency. Then, a trend analysis was performed on mean values evaluated at annual and seasonal scales through the non-parametric Mann–Kendall test for three different significance levels equal to 90%, 95% and 99%. The obtained results could be useful for analyses linked to beach morphodynamics and on the identification of field installations of Wave Energy Converters (WECs).

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Prediction of the wave power in the Black Sea based on wind speed using artificial neural networks

E3S Web of Conferences ◽

10.1051/e3sconf/20185101006 ◽

2018 ◽

Vol 51 ◽

pp. 01006

Author(s):

Sorin Ciortan ◽

Eugen Rusu

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Wind Speed ◽

Wave Height ◽

Black Sea ◽

Significant Wave Height ◽

The Black Sea ◽

Wave Power ◽

Significant Wave ◽

Artificial Neural

The paper proposes a prediction methodology for the significant wave height (and implicitly the wave power), based on the artificial neural networks. The proposed approach takes as input data the wind speed values recorded for different time periods. The prediction of significant wave height is useful both for assessment of wave energy as also for marine equipment design and navigation. The data used cover the time interval 1999 to 2007 and it was measured on Gloria drilling unit, which operates in the Romanian nearshore of the Black Sea at about 500 meters depth.

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Advanced Altimeter Interferometry for Modelling the Wave Pattern Impacts of MH370 Flaperon

Genetic Algorithms and Remote Sensing Technology for Tracking Flight Debris - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-7998-1920-2.ch011 ◽

2020 ◽

pp. 226-250

Keyword(s):

Indian Ocean ◽

Wave Height ◽

Significant Wave Height ◽

Wave Pattern ◽

Wave Power ◽

The Novel ◽

M Wave ◽

Significant Wave ◽

Novel Approach ◽

The Indian Ocean

Previous studies investigated the Indian Ocean's currents' impacts on the trajectory movement of MH370 debris. This chapter introduces the novel approach of investigating the wave pattern variations in the Indian Ocean on the MH370 debris. The novel approach based on the altimeter interferometry technique is utilized in this chapter. To this end, dual SIRAL instruments on-board of CryoSat-2 are applied to obtain the annual cycle of significant wave height across the Indian Ocean. In this chapter, in a one-year significant wave height cycle, the swell remains propagating from the Southwest to the Northeast from January to March 2015 with a maximum significant wave height of 5 m in the Northeast Offshore Australian Shelf and 7 m significant wave height Southwest of Australian Shelf. In this circumstance, the Pareto algorithm proves that the flaperon would submerge to a water depth less than 300 m on account of the impact of wave power of 22000 KJ/m/wave. It can be said that the flaperon would be submerged further to a water depth of 1000 m because of the wave power of 30000 KJ/m/wave.

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Wave Power Statistics for Sea States

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4002739 ◽

2011 ◽

Vol 133 (4) ◽

Cited By ~ 3

Author(s):

Dag Myrhaug ◽

Bernt J. Leira ◽

Håvard Holm

Keyword(s):

Wave Height ◽

Significant Wave Height ◽

Wave Climate ◽

Bivariate Distribution ◽

Wave Power ◽

Power Devices ◽

Characteristic Wave ◽

Significant Wave ◽

Wave Power Potential

This paper provides a bivariate distribution of wave power and significant wave height, as well as a bivariate distribution of wave power and a characteristic wave period for sea states, and the statistical aspects of wave power for sea states are discussed. This is relevant for, e.g., making assessments of wave power devices and their potential for converting energy from waves. The results can be applied to compare systematically the wave power potential at different locations based on long term statistical description of the wave climate.

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Wave Analysis for Offshore Aquaculture Projects: A Case Study for the Eastern Mediterranean Sea

Climate ◽

10.3390/cli10010002 ◽

2022 ◽

Vol 10 (1) ◽

pp. 2

Author(s):

Flora E. Karathanasi ◽

Takvor H. Soukissian ◽

Daniel R. Hayes

Keyword(s):

Mediterranean Sea ◽

Wave Height ◽

Significant Wave Height ◽

Eastern Mediterranean ◽

Wave Climate ◽

Eastern Mediterranean Sea ◽

Significant Wave ◽

Offshore Aquaculture

The investigation of wave climate is of primary concern for the successful implementation of offshore aquaculture systems as waves can cause significant loads on them. Up until now, site selection and design (or selection) of offshore cage system structures on extended sea areas do not seem to follow any specific guidelines. This paper presents a novel methodology for the identification of favorable sites for offshore aquaculture development in an extended sea area based on two important technical factors: (i) the detailed characterization of the wave climate, and (ii) the water depth. Long-term statistics of the significant wave height, peak wave period, and wave steepness are estimated on an annual and monthly temporal scale, along with variability measures. Extreme value analysis is applied to estimate the design values and associated return periods of the significant wave height; structures should be designed based on this data, to avoid partial or total failure. The Eastern Mediterranean Sea is selected as a case study, and long-term time series of wave spectral parameters from the ERA5 dataset are utilized. Based on the obtained results, the most favorable areas for offshore aquaculture installations have been identified.

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Wave Power Statistics for Sea States

Volume 4: Ocean Engineering; Ocean Renewable Energy; Ocean Space Utilization, Parts A and B ◽

10.1115/omae2009-79132 ◽

2009 ◽

Cited By ~ 2

Author(s):

Dag Myrhaug ◽

Bernt J. Leira ◽

Ha˚vard Holm

Keyword(s):

Wave Height ◽

Significant Wave Height ◽

Wave Climate ◽

Bivariate Distribution ◽

Wave Power ◽

Power Devices ◽

Significant Wave ◽

Wave Power Potential

The paper provides a bivariate distribution of wave power and significant wave height, and the statistical aspects of wave power for sea states are discussed. This is relevant for e.g. making assessments of wave power devices and their potential for converting energy from waves. The results can be applied to compare systematically the wave power potential at different locations based on long term statistical description of the wave climate.

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A Dynamic Stochastic Hybrid Model to Represent Significant Wave Height and Wave Period for Marine Energy Representation

Energies ◽

10.3390/en12050887 ◽

2019 ◽

Vol 12 (5) ◽

pp. 887

Author(s):

Humberto Verdejo ◽

Almendra Awerkin ◽

Wolfgang Kliemann ◽

Cristhian Becker ◽

Héctor Chávez ◽

...

Keyword(s):

Power Generation ◽

Hybrid Model ◽

Wave Height ◽

Significant Wave Height ◽

Wave Period ◽

Estimation Methods ◽

Wave Power ◽

Significant Wave ◽

Dynamic Stochastic ◽

Wave Power Generation

This paper presents a methodology to represent ocean wave power generation based on real data observation for significant wave height (SWH or H s ) and wave period (WP or T). This technique is based on a hybrid model, which considers Fourier series and stochastic differential equations, allowing a continuous time representation of the random changes in the parameters associated with wave power generation ( H s and T). The methodology is explained, including estimation methods and a validation procedure. The data series generated by the models erre used to create simulated wave power output applying a transformed matrix and a theoretical model. The results validate the utilization of this technique, when the objective is to obtain a robust dynamic representation of a random process, oriented to linear studies.

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