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This study aims to investigate the quality of ERA5, a recent reanalysis wind product, and its contribution to wave modelling performance in a semi-closed sea, the Black Sea. This investigation includes a comparison of ERA5 surface wind fields with the ones from the CFSR to assess if this latest reanalysis improved the representation of the surface winds. Wind speeds from both reanalyses were validated with measurements at Gloria, the only sea wind measurement station on the Black Sea. Validations were also conducted using altimeter and scatterometer satellite data after which results were later compared against each other. The second aim of this study investigates whether a wave hindcast model forced with the ERA5 wind fields has improved prediction of wave parameters. A SWAN model with default settings was used to compare the results under the same conditions. Performance analyzes of the default SWAN wave estimates with both ERA5 and CFSR winds were conducted using three offshore buoy measurements and altimeter data of satellites over the Black Sea. Results show that ERA5 winds are more biased compared to CFSR winds at Gloria location. Both CFSR and ERA5 underestimate wind speeds. ERA5 performs better than the CFSR in lower wind speeds and worse in higher wind speeds. However, ERA5 winds have less bias and are more scattered than the CFSR winds against the satellite data. SWAN driven by CFSR winds performs better than the one driven by ERA5 winds against both buoy and satellite data.
Emre Çalışır; Mehmet Burak Soran; Adem Akpınar. Quality of the ERA5 and CFSR winds and their contribution to wave modelling performance in a semi-closed sea. Journal of Operational Oceanography 2021, 1 -25.
AMA StyleEmre Çalışır, Mehmet Burak Soran, Adem Akpınar. Quality of the ERA5 and CFSR winds and their contribution to wave modelling performance in a semi-closed sea. Journal of Operational Oceanography. 2021; ():1-25.
Chicago/Turabian StyleEmre Çalışır; Mehmet Burak Soran; Adem Akpınar. 2021. "Quality of the ERA5 and CFSR winds and their contribution to wave modelling performance in a semi-closed sea." Journal of Operational Oceanography , no. : 1-25.
This study aims to determine long-term spatial variability of wind and wave characteristics over the Sea of Marmara. For this purpose, we produced four different wind and wave datasets for a period of 40 years (1979–2018) using the calibrated and default-setting SWAN models forced with both CFSR and ERA-Interim winds and inter-compared. The performance of these datasets is examined against the wave height measurements of 2015 at the Silivri buoy station and 27-year (1991–2018) satellites data (ENVISAT, ERS-1, ERS-2, JASON-1, JASON-2, JASON-3, SENTINEL-3A, SENTINEL-3B, TOPEX). Then, for wind and wave climate analysis, the spatial distributions of the wind and wave characteristics over the study area are determined in terms of seasonal and annual averages. 40-year averages of 95th and 99th percentile significant wave heights, probabilities of being larger than significant wave heights exceeding a critical value, and 40-year maximum significant wave heights are spatially analyzed. Finally, the calibrated SWAN model using CFSR winds presents the most accurate results. Therefore, the effects of different model inputs and settings on the model results are examined by creating spatial distributions of the biases of the other three model results and comparing them to those of the calibrated model results using CFSR winds. The CFSR forced and calibrated model predicts the largest average wind speed and average wave height in the central regions of the Sea of Marmara in comparison with the other three models. The shores of Kapidag Peninsula and Marmara Island are exposed to be with the highest wave conditions.
Adem Akpınar; Volkan Kutupoğlu; Bilal Bingölbali; Emre Çalışır. Spatial characteristics of wind and wave parameters over the Sea of Marmara. Ocean Engineering 2021, 222, 108640 .
AMA StyleAdem Akpınar, Volkan Kutupoğlu, Bilal Bingölbali, Emre Çalışır. Spatial characteristics of wind and wave parameters over the Sea of Marmara. Ocean Engineering. 2021; 222 ():108640.
Chicago/Turabian StyleAdem Akpınar; Volkan Kutupoğlu; Bilal Bingölbali; Emre Çalışır. 2021. "Spatial characteristics of wind and wave parameters over the Sea of Marmara." Ocean Engineering 222, no. : 108640.
This study focuses on the inter- and intra-annual variation in theoretical wave power along the south-western coast of the Black Sea. Long-term (1979–2009) hindcast developed using the calibrated three-layer nested SWAN model was used for a detailed assessment of wave energy resource. Annual change, monthly and seasonal wave power variability indices were evaluated, and the Optimal Hotspot Index (OHI) was calculated for 62 sites along the coast to rate the hotspot locations. The assessment shows the highest wave energy resources in western Karaburun with higher variability. However, the western Sinop sites have lower wave energy resources compared to western Karaburun sites, in spite of considering the lower variability, these sites are more appropriate for wave energy extraction. The location with the highest potential (KA5 100 m depth) has an average of 8.4 kW/m and a maximum of 1015 kW/m wave power capacity. The east sites of Sinop and Filyos are comparatively less dynamic. Moreover, it was found that the average peak values of wave heights are in February, and the lowest sea state was in June. 2003 was the most, and 1989 was the least energetic years in the 31-year period.
Bilal Bingölbali; Ajab Gul Majidi; Adem Akpınar. Inter- and intra-annual wave energy resource assessment in the south-western Black Sea coast. Renewable Energy 2021, 169, 809 -819.
AMA StyleBilal Bingölbali, Ajab Gul Majidi, Adem Akpınar. Inter- and intra-annual wave energy resource assessment in the south-western Black Sea coast. Renewable Energy. 2021; 169 ():809-819.
Chicago/Turabian StyleBilal Bingölbali; Ajab Gul Majidi; Adem Akpınar. 2021. "Inter- and intra-annual wave energy resource assessment in the south-western Black Sea coast." Renewable Energy 169, no. : 809-819.
Annual trends in storm wave intensity over the past 41 years were evaluated during the present study. Storm wave intensity is evaluated in terms of total storm wave energy (TSWE) and storm power index (SPI) of Dolan and Davis (1992). Using an accurate long-term wave hindcast developed using a calibrated SWAN model, all storm wave events occurring over the past 41 years were characterized in terms of significant wave height (Hs) and total storm duration. Thus, both SPI and TSWE was computed for each storm wave event. The Theil–Sen slope estimator was used to estimate the annual slopes of the SPI and TSWE and the Mann–Kendall test was used to test the trend significance with different confidence levels. The present study is spatially performed for the western Mediterranean Sea basin considering 2308 grid points in a regular grid of 0.198° resolution in both directions. Results allow as to define five hotspots covering a large area, experienced a significant increasing slope in both SPI and TSWE (annual maxima and average). The confidence level in this area exceed 95%, with a steep slope between 100 kWh·m−1·year−1 and 240 kWh·m−1·year−1 for annual max TSWE and between 28 m²·h·year−1 and 49 m²·h·year−1 for annual max SPI. Consideration of the present findings is strongly recommended for risk assessment and for sustainable development in coastal and offshore area and to identify areas sensitive to global climate change in the western Mediterranean Sea.
Khalid Amarouche; Adem Akpınar. Increasing Trend on Storm Wave Intensity in the Western Mediterranean. Climate 2021, 9, 11 .
AMA StyleKhalid Amarouche, Adem Akpınar. Increasing Trend on Storm Wave Intensity in the Western Mediterranean. Climate. 2021; 9 (1):11.
Chicago/Turabian StyleKhalid Amarouche; Adem Akpınar. 2021. "Increasing Trend on Storm Wave Intensity in the Western Mediterranean." Climate 9, no. 1: 11.
The paper focuses on the performance and determination of optimal installation depths of wave energy converter systems (WECs) in less intensified wave energy locations. Therefore, the study aims to investigate the changes in wave power production performance of different WECs along the coastline of the south-western parts of the Black Sea, a semi-enclosed sea. For this purpose, the data needed was extracted from the dataset produced for the period 1979 to 2009 using a calibrated nested layered wave hindcast SWAN version 41.01AB model forced with CFSR winds. The discussion focuses on the most essential five statistical parameters (dimensionless normalized wave power, efficiency index, capacity factor, capture width and energy production per unit of rated power) that can present an easy and more precise idea about the power production performance of WECs at different depths. The results present that the wave energy resource intensity is generally decreasing gradually from Karaburun to Sinop in the study area; the most energy intensified location is line KA, and the Oceantec WECs shows the best performance in its installation depth range. At different locations and depths, different WECs are more suitable for installation.
Ajab Gul Majidi; Bilal Bingölbali; Adem Akpınar; Eugen Rusu. Wave power performance of wave energy converters at high-energy areas of a semi-enclosed sea. Energy 2020, 220, 119705 .
AMA StyleAjab Gul Majidi, Bilal Bingölbali, Adem Akpınar, Eugen Rusu. Wave power performance of wave energy converters at high-energy areas of a semi-enclosed sea. Energy. 2020; 220 ():119705.
Chicago/Turabian StyleAjab Gul Majidi; Bilal Bingölbali; Adem Akpınar; Eugen Rusu. 2020. "Wave power performance of wave energy converters at high-energy areas of a semi-enclosed sea." Energy 220, no. : 119705.
As wave energy converters (WECs) are typically designed and optimized for ocean wave conditions, they struggle to perform in low-energy seas or bays, where wave conditions are very different. This work investigates the hypothesis that downscaled versions of WECs may well be more suited for such conditions. More specifically, fifteen downscaled WECs are considered for deployment in the Black Sea. The resizing (downscaling) of the WECs is based on Froude scaling law. Ten values are considered for the scaling factor (λL = 1.0, 0.9, 0.8 … 0.1), and the value that yields the highest capacity factor is selected for downscaling the WEC. The downscaled WEC is then compared with the original (full-scale) WEC in terms of performance (capacity factor, full-load hours, and rated capacity). This analysis is carried out for fifteen WECs and 62 locations at different water depths (5, 25, 50, 75, and 100 m), distributed on 13 lines perpendicular to the shoreline along the south-western coast of the Black Sea. The highest capacity factor was obtained by Oyster, whereas the highest energy output was achieved by SSG and WaveDragon for the locations with 4–16 m depths. For deeper waters (25, 50, 75, and 100 m), the highest capacity factor was obtained by Oceantec. In terms of energy output, the best performers were WaveDragon (at 25 m water depth) and Pontoon (at 50, 75, and 100 m water depths). The interest of this approach, however, lies not only in that it enables a scaling factor to be determined for downscaling a WEC for a given site, but also – and more generally – in that it proves the initial hypothesis that downscaled WECs may provide a better alternative for low-energy seas than their full-scale counterparts.
AjabGul Majidi; Bilal Bingölbali; Adem Akpınar; Gregorio Iglesias; Halid Jafali. Downscaling wave energy converters for optimum performance in low-energy seas. Renewable Energy 2020, 168, 705 -722.
AMA StyleAjabGul Majidi, Bilal Bingölbali, Adem Akpınar, Gregorio Iglesias, Halid Jafali. Downscaling wave energy converters for optimum performance in low-energy seas. Renewable Energy. 2020; 168 ():705-722.
Chicago/Turabian StyleAjabGul Majidi; Bilal Bingölbali; Adem Akpınar; Gregorio Iglesias; Halid Jafali. 2020. "Downscaling wave energy converters for optimum performance in low-energy seas." Renewable Energy 168, no. : 705-722.
The present study aims to determine priority areas for installation of wave energy converters (WECs) in a semi-enclosed sea using a multi-criteria, spatial, decision-making analysis based on geographical information systems (GIS). The study also suggests a new methodology for determination of suitable areas for WECs taking into consideration different extreme wave conditions, intra-annual variation of wave conditions, and operational range of wave conditions by the WECs. A case study over a distance of 1140 km along the coast in the southwest Black Sea is presented. In the multi-criteria analysis, areas with environmental, economic, technical and social constraints are excluded. Ocean depth, distance to ports, shore, power line, and sub-station, wave climate, and sea-floor geology are all evaluated for their impact on the system implementation and weighted according to their relevance. Thus, the final suitability index (SI) map is produced and spatial statistical significance of the suitable areas is checked using hotspot analysis. Based on this, Kırklareli coastal area and the area between İğneada Cape and Kıyıköy village are determined as primary priority areas. The sustainability parameters with different weights proposed in this study do not differentiate priority areas but affect the SI scores.
Murat Şan; Adem Akpınar; Bilal Bingölbali; Murat Kankal. Geo-spatial multi-criteria evaluation of wave energy exploitation in a semi-enclosed sea. Energy 2020, 214, 118997 .
AMA StyleMurat Şan, Adem Akpınar, Bilal Bingölbali, Murat Kankal. Geo-spatial multi-criteria evaluation of wave energy exploitation in a semi-enclosed sea. Energy. 2020; 214 ():118997.
Chicago/Turabian StyleMurat Şan; Adem Akpınar; Bilal Bingölbali; Murat Kankal. 2020. "Geo-spatial multi-criteria evaluation of wave energy exploitation in a semi-enclosed sea." Energy 214, no. : 118997.
This study concentrates on the changes of theoretical wave power from offshore to coastal regions of south-western Black Sea. The investigation also offers a long-term (31-year) wave power quantification analysis between 1979 and 2009 using the SWAN version 41.01AB numerical wave model. The wave resource assessment is performed in terms of its seasonal and monthly variability of wave power, annual wave power directional distributions and the comparison of the maximum and median values of some important wave power parameters in the west of Istanbul a major city in Turkey that straddles Europe and Asia across the Bosphorus Strait. For this analysis, 10 point locations distributed on two perpendicular lines (KA and KE) to the coastline with five different depths (5, 25, 50, 75, and 100 m) in the areas of interest were selected. The data needed was extracted from the dataset produced by [1, 2] using a calibrated nested layered wave hindcast model SWAN forced with CFSR winds. The results show that the wave energy resource in the study area is high, and the potential locations can be considered for extracting wave electrical power.
Ajab Gul Majidi; Bilal Bingölbali; Adem Akpınar. The Changes of Theoretical Wave Power from Offshore to Coast in the South-western Black Sea. E3S Web of Conferences 2020, 191, 03004 .
AMA StyleAjab Gul Majidi, Bilal Bingölbali, Adem Akpınar. The Changes of Theoretical Wave Power from Offshore to Coast in the South-western Black Sea. E3S Web of Conferences. 2020; 191 ():03004.
Chicago/Turabian StyleAjab Gul Majidi; Bilal Bingölbali; Adem Akpınar. 2020. "The Changes of Theoretical Wave Power from Offshore to Coast in the South-western Black Sea." E3S Web of Conferences 191, no. : 03004.
This study aims at the assessment of wave energy potential and its spatial and temporal variability along the south-west coasts in the hot-spot areas of Black Sea. For this purpose, third-generation numerical wave hindcast model Simulating WAve Nearshore (SWAN), which is based on a set of nested SWAN model with increasing spatial resolutions (a coarse grid, then a fine grid, and then three sub-grids), forced with the Climate Forecast System Reanalysis (CFSR) winds is used to produce long term wave characteristics during the 31 years in the areas of interest. For the south-west coasts of the Black Sea the best nested SWAN model configuration, developed in our previous studies [1,2], with tuned coefficients for all of the deep and shallow water source terms in modelling of the wind-generated waves is run to obtain spatial and temporal outputs of several wind wave parameters for the assessment of wave energy potential and its variability. By using this data set, temporal and spatial variability of wave energy potential along the south western Black Sea is analysed in detail, considering annual, seasonal, and monthly spatial variation maps of wave power for each of the sub-grids. In addition, annual, seasonal, and monthly wave power potential variability, the exceedance probability curves, the value of wave energy resource potential, and wave power roses are established for several locations. The value of energy density, spatial variation of the stability of energy density (the coefficient of variation, monthly variability index, seasonal variability index, and persistency analysis), spatial variation of total storage and exploitable storage of wave energy resource are also analysed. Finally, it was determined that in the regions (Karaburun SD3 sub-grid domain) where the average wave energy flux is high, the wave energy flux has a high coefficient of variation, and thus the regions (Filyos SD2 sub-grid domain) having lower wave energy flux have a stable wave energy flux which is ideal for energy exploitation from waves. Annual average wave energy in the southwestern part of the Black Sea is concentrated at 0.2–1.5 m significant wave height range, and also the concentration is between 2 and 5 s in Karaburun SD3, 3–7 s in Filyos SD2 and 2.5–6.5 s in Sinop SD1 sub-grid domains in terms of the wave energy period.
Bilal Bingölbali; Halid Jafali; Adem Akpınar; Serkan Bekiroğlu. Wave energy potential and variability for the south west coasts of the Black Sea: The WEB-based wave energy atlas. Renewable Energy 2020, 154, 136 -150.
AMA StyleBilal Bingölbali, Halid Jafali, Adem Akpınar, Serkan Bekiroğlu. Wave energy potential and variability for the south west coasts of the Black Sea: The WEB-based wave energy atlas. Renewable Energy. 2020; 154 ():136-150.
Chicago/Turabian StyleBilal Bingölbali; Halid Jafali; Adem Akpınar; Serkan Bekiroğlu. 2020. "Wave energy potential and variability for the south west coasts of the Black Sea: The WEB-based wave energy atlas." Renewable Energy 154, no. : 136-150.
This paper aims to examine the temporal variation of wave energy flux in the hotspot areas of the Black Sea. For this purpose, a 31-year long-term wave dataset produced by using a three-layered nested modelling system was used. Temporal variations of wave energy were determined at hourly, monthly, seasonal, and yearly basis at seventeen stations. Based on the results obtained, it can be concluded that the stations have very low fluctuations in mean wave power during the day. Mean wave power in the summer months shows a low difference between the stations, but in the winter months, there is a higher difference in wave power between the stations. This difference is more at the stations in the southwestern part of the Black Sea and much lower in the eastern Black Sea stations around Sinop, being in the middle of the southern coast of the Black Sea. In addition, it is concluded that mean wave energy flux presents a decreasing trend at all stations, but maximum wave power offers an increasing trend at most of the stations.
Adem Akpınar; Halid Jafali; Eugen Rusu. Temporal Variation of the Wave Energy Flux in Hotspot Areas of the Black Sea. Sustainability 2019, 11, 562 .
AMA StyleAdem Akpınar, Halid Jafali, Eugen Rusu. Temporal Variation of the Wave Energy Flux in Hotspot Areas of the Black Sea. Sustainability. 2019; 11 (3):562.
Chicago/Turabian StyleAdem Akpınar; Halid Jafali; Eugen Rusu. 2019. "Temporal Variation of the Wave Energy Flux in Hotspot Areas of the Black Sea." Sustainability 11, no. 3: 562.
This study aims to present an evaluation and implementation of a high-resolution SWAN wind wave hindcast model forced by the CFSR wind fields in the west Mediterranean basin, taking into account the recent developments in wave modelling as the new source terms package ST6. For this purpose, the SWAN model was calibrated based on one-year wave observations of Azeffoune buoy (Algerian coast) and validated against eleven wave buoys measurements through the West Mediterranean basin. For the calibration process, we focused on the whitecapping dissipation coefficient Cds and on the exponential wind wave growth and whitecapping dissipation source terms. The statistical error analysis of the calibration results led to conclude that the SWAN model calibration corrected the underestimation of the significant wave height hindcasts in the default mode and improved its accuracy in the West Mediterranean basin. The exponential wind wave growth of Komen et al (1984) and the whitecapping dissipation source terms of Janssen (1991) with Cds = 1.0 have been thus recommended for the western Mediterranean basin. The comparison of the simulation results obtained using this calibrated parameters against eleven measurement buoys showed a high performance of the calibrated SWAN model with an average scatter index of 30% for the significant wave heights and 19% for the mean wave period. This calibrated SWAN model will constitute a practical wave hindcast model with high spatial resolution (˜3 km) and high accuracy in the Algerian basin, which will allow us to proceed to a finer mesh size using the SWAN nested grid system in this area.
Khalid Amarouche; Adem Akpınar; Nour El Islam Bachari; Recep Emre Çakmak; Fouzia Houma. Evaluation of a high-resolution wave hindcast model SWAN for the West Mediterranean basin. Applied Ocean Research 2019, 84, 225 -241.
AMA StyleKhalid Amarouche, Adem Akpınar, Nour El Islam Bachari, Recep Emre Çakmak, Fouzia Houma. Evaluation of a high-resolution wave hindcast model SWAN for the West Mediterranean basin. Applied Ocean Research. 2019; 84 ():225-241.
Chicago/Turabian StyleKhalid Amarouche; Adem Akpınar; Nour El Islam Bachari; Recep Emre Çakmak; Fouzia Houma. 2019. "Evaluation of a high-resolution wave hindcast model SWAN for the West Mediterranean basin." Applied Ocean Research 84, no. : 225-241.
This study presents the south-west Black Sea wave climatology based on a downscaling approach of a long-term 31-year SWAN model wave hindcast using telescoping nested grids. At all domains the SWAN model is forced with the CFSR winds. Sensitivity tests are conducted on domain size, computational resolutions, the physical formulations and their adjustable coefficients for deep water source terms, time step of non-stationary calculation, and wind forcing for all domains. For each nested grid the physical and numerical settings were determined separately by calibration against wave buoy measurements at six locations (Gelendzhik, Hopa, Sinop, Gloria, Filyos, and Karaburun) in appropriate domains. Model validation is also conducted for the long-term data using the unused measurements in the calibration. Using the calibrated nested models, a 31-year long-term wave hindcast is conducted. Two-hourly sea state parameters of significant wave height (Hm0), wave energy period (Tm-10), spectral period (Tm01), zero-crossing period (Tm02), peak period (Tp), wind speed components, and mean wave direction (DIR) were collected over three sub-grid domains. Using this database normal and extreme wave conditions in the three sub-grid domains were determined. Finally, extreme waves with different return periods were determined and compared with those presented in the Wind and Deep Water Wave Atlas of Özhan and Abdalla (2002). The present study demonstrates the sensitivity of the SWAN model towards different GEN3 physics options and its adjustable whitecapping parameter Cds and time step of the non-stationary calculations. It is shown that the developed wave model set-up with a nested grid system performs quite satisfactorily and storms are also well-captured. This study yields higher extreme waves in the western part of our area of interest and lower extremes in the eastern part in comparison with those of the presently used Wind and Deep Water Wave Atlas.
Bilal Bingölbali; Adem Akpınar; Halid Jafali; Gerbrant Ph Van Vledder. Downscaling of wave climate in the western Black Sea. Ocean Engineering 2018, 172, 31 -45.
AMA StyleBilal Bingölbali, Adem Akpınar, Halid Jafali, Gerbrant Ph Van Vledder. Downscaling of wave climate in the western Black Sea. Ocean Engineering. 2018; 172 ():31-45.
Chicago/Turabian StyleBilal Bingölbali; Adem Akpınar; Halid Jafali; Gerbrant Ph Van Vledder. 2018. "Downscaling of wave climate in the western Black Sea." Ocean Engineering 172, no. : 31-45.
A high-resolution SWAN wind wave hindcast model was implemented for the Sea of Marmara. For this, we focused firstly on the quality of two data sources for the wind forcing, viz., the ERA-Interim winds from the ECMWF and CFSR winds from the NOAA/NCEP. These were compared against wind measurements for 2013 collected at the Silivri offshore buoy in the north of the Sea of Marmara. A sensitivity analysis was performed to find the optimal numerical settings and wind source. This analysis showed that the CFSR winds are most suited for wave modelling in the Sea of Marmara. As the Sea of Marmara can practically be considered as deep water, we calibrated the SWAN model for different combinations of wind input and whitecapping source terms. The calibration was performed by varying the whitecapping coefficient for different combinations. The model setting giving the lowest errors and highest correlation via sensitivity analysis was determined as the calibrated model. Thirdly, the calibrated model was validated against measurements at the Silivri buoy for the years 2014, 2015 and 2016. This validation confirmed that the calibrated SWAN model with CFSR wind forcing performed better than the default settings. Lastly, the performance of the calibrated SWAN model was assessed for different wave height ranges, wind sources, annually and per season, their directional properties using wind and wave roses, their distribution function and Quantile – Quantile plots along with extreme waves. The calibrated model offers almost the same extreme waves with different recurrent periods as the measurements.
Volkan Kutupoğlu; Recep Emre Çakmak; Adem Akpınar; Gerbrant Ph. van Vledder. Setup and evaluation of a SWAN wind wave model for the Sea of Marmara. Ocean Engineering 2018, 165, 450 -464.
AMA StyleVolkan Kutupoğlu, Recep Emre Çakmak, Adem Akpınar, Gerbrant Ph. van Vledder. Setup and evaluation of a SWAN wind wave model for the Sea of Marmara. Ocean Engineering. 2018; 165 ():450-464.
Chicago/Turabian StyleVolkan Kutupoğlu; Recep Emre Çakmak; Adem Akpınar; Gerbrant Ph. van Vledder. 2018. "Setup and evaluation of a SWAN wind wave model for the Sea of Marmara." Ocean Engineering 165, no. : 450-464.
Spatial and temporal variations of significant wave height (H m0) and wind speed (WS) at selected locations over the Black Sea are studied based on 31-year long-term SWAN simulations forced with Climate Forecast System Reanalysis dataset. The objective was to investigate whether or not there is a possible increase in wind and wave conditions along the Black Sea shelves. Wind and wave parameters are obtained at 33 locations enclosing the Black Sea coast line from SWAN simulations and annual mean and maximum H m0 and WS values as the climatological variables are computed for these locations. Using these data, long-term trends and their significance at these locations are investigated based on Mann–Kendall trend test. To quantify the trends, Sen’s slope estimator and least square linear regression (the slope of the linear best-fit curve) are used. Variation of monthly mean H m0 and WS values at these locations are also discussed. Besides, decadal variations of these four climatological variables at 33 locations are studied. The results show that higher wind speeds and wind wave heights are monitored in the winter season in all locations, while during the summer months, there is a significant drop in both H m0 and WS. In the western Black Sea, average H m0 is highest (about 1.02 m) at locations 23 and 25. During the period of 1979 and 2009, it is determined that mean WS has a weak significant increasing trend (maximum 1.29 cm/s/year) along the north-eastern coasts of Turkey and the Crimean peninsula, while there is no statistically significant H m0 trend in the Black Sea except at location 11, offshore Sochi in the north-eastern part of the Black Sea. A weak decreasing trend (maximum 0.24 cm/year) in mean H m0 is seen along the north-western coasts of Turkey, while maximum H m0 and WS show no statistically significant increasing or decreasing trend except location 2, which has a weak significant increasing trend for maximum WS. All the trends at other locations for four variables are statistically insignificant, and they have no trend. The most significant difference is observed in maximum WS as 6.14 m/s in different decades in the north-western part of the Black Sea. The difference in the decades is very low in mean H m0 at all locations. Mean wind and wave conditions at all locations have almost negligible difference, whereas decadal variations of maximum H m0 and WS show high differences. This may be probably due to storms and cyclones conditions.
Adem Akpınar; Bilal Bingölbali. Long-term variations of wind and wave conditions in the coastal regions of the Black Sea. Natural Hazards 2016, 84, 69 -92.
AMA StyleAdem Akpınar, Bilal Bingölbali. Long-term variations of wind and wave conditions in the coastal regions of the Black Sea. Natural Hazards. 2016; 84 (1):69-92.
Chicago/Turabian StyleAdem Akpınar; Bilal Bingölbali. 2016. "Long-term variations of wind and wave conditions in the coastal regions of the Black Sea." Natural Hazards 84, no. 1: 69-92.
This paper evaluates the impact of using different wind field products on the performance of the third generation wave model SWAN in the Black Sea and its capability for predicting both normal and extreme wave conditions during 1996. Wind data were obtained from NCEP CFSR, NASA MERRA, JRA-25, ECMWF Operational, ECMWF ERA40, and ECMWF ERA-Interim. Wave data were obtained in 1996 at three locations in the Black Sea within the NATO TU-WAVES project. The quality of wind fields was assessed by comparing them with satellite data. These wind data were used as forcing fields for the generation of wind waves. Time series of predicted significant wave height (Hmo), mean wave period (Tm02), and mean wave direction (DIR) were compared with observations at three offshore buoys in the Black Sea and its performance was quantified in terms of statistical parameters. In addition, wave model performance in terms of significant wave height was also assessed by comparing them against satellite data. The main scope of this work is the impact of the different available wind field products on the wave hindcast performance. In addition, the sensitivity of wave model forecasts due to variations in spatial and temporal resolutions of the wind field products was investigated. Finally, the impact of using various wind field products on predicting extreme wave events was analyzed by focussing on storm peaks and on an individual storm event in October 1996. The numerical results revealed that the CFSR winds are more suitable in comparison with the others for modelling both normal and extreme events in the Black Sea. The results also show that wave model output is critically sensitive to the choice of the wind field product, such that the quality of the wind fields is reflected in the quality of the wave predictions. A finer wind spatial resolution leads to an improvement of the wave model predictions, while a finer temporal resolution in the wind fields generally does not significantly improve agreement between observed and simulated wave data.
Gerbrant Ph. Van Vledder; Adem Akpınar. Wave model predictions in the Black Sea: Sensitivity to wind fields. Applied Ocean Research 2015, 53, 161 -178.
AMA StyleGerbrant Ph. Van Vledder, Adem Akpınar. Wave model predictions in the Black Sea: Sensitivity to wind fields. Applied Ocean Research. 2015; 53 ():161-178.
Chicago/Turabian StyleGerbrant Ph. Van Vledder; Adem Akpınar. 2015. "Wave model predictions in the Black Sea: Sensitivity to wind fields." Applied Ocean Research 53, no. : 161-178.