Current velocity, temperature and oil thickness as determinants of the refloating process of stranded oil in the Bohai Sea

2020 ◽  
Vol 71 (8) ◽  
pp. 1006
Author(s):  
Yue Yu ◽  
Zhixin Qi ◽  
Xinping Yu ◽  
Wenxin Li ◽  
Sinan Fu ◽  
...  
Keyword(s):  
Current Velocity ◽  
Bohai Sea ◽  
Fate And Transport ◽  
Hydrodynamic Conditions ◽  
Oil Viscosity ◽  
The Bohai Sea ◽  
Positive Linear Correlation ◽  
Flow Through ◽  
Effects Of Temperature ◽  
Oil Thickness

After oil spill accidents, weathered oil slicks can drift to coastal areas and interact with shoreline substrates. This process has been demonstrated to be the cause of the formation of stranded oil, which has attracted much attention. However, the refloating process of stranded oil when coastal hydrodynamic conditions change has been little investigated. This study evaluated the effects of current velocity, temperature and oil thickness on the refloating process of a simulated oil patty in a flow-through tank. The oil refloating efficiency (ORE) was used to quantitatively examine the degree of refloating. Non-linear fitting results indicated that the ORE increased gradually over time and then plateaued. Both observations and measurements indicated that higher current velocity brought about more oil refloat and enhanced the oil refloating rate. Furthermore, both the mass of refloating oil and the oil refloating rate showed a positive linear correlation with current velocity. The effects of temperature on the oil refloating process were determined by the effects of temperature on oil viscosity. In addition, the ORE at equilibrium increased linearly with increasing oil thickness. An empirical model was introduced and found to be closely consistent with the experimental data. This information is useful in predicting the fate and transport of stranded oil in the Bohai Sea.

Design Parameter Estimation Under Multivariate Extreme Ocean Environmental Conditions in the Bohai Sea

2007 ◽  
Author(s):  
Sheng Dong ◽  
Liang Wang ◽  
Xinyu Fu
Keyword(s):  
Parameter Estimation ◽  
Wind Speed ◽  
Wave Height ◽  
Environmental Conditions ◽  
Current Velocity ◽  
Bohai Sea ◽  
Distribution Model ◽  
Logistic Distribution ◽  
Mathematical Form ◽  
The Bohai Sea

On the basis of 21 years hindcasted data in the Bohai Sea, a Trivariate Nested Logistic Distribution model is utilized to calculate the joint probability of extreme environmental conditions, such as wind speed, significant wave height, and current velocity, which simultaneously occur during storm processes. Statistical analysis shows that this approach is simple in mathematical form, explicit in its expression, and can be easily applied to parameter estimation. It involves hierarchical dependence and can be applied to a wider field than the symmetric Logistic model. The ocean environmental contours in three demensions are created rather than the usual two. The contours as slices through return periods of wind speed is displayed to find the mode of wave height and current velocity. Based on the multivariate extreme value distribution theory, the determination of environmental parameter values will be objective and reasonable in engineering design.

Keystone species of fish community structure in the Bohai Sea

2018 ◽  
Vol 25 (2) ◽  
pp. 229
Author(s):  
Zhongyi LI ◽  
Qiang WU ◽  
Xiujuan SHAN ◽  
Tao YANG ◽  
Fangqun DAI ◽  
...  
Keyword(s):  
Community Structure ◽  
Fish Community ◽  
Bohai Sea ◽  
Keystone Species ◽  
Fish Community Structure ◽  
The Bohai Sea

Species Diversity and Eco-geographical Distribution of Dinoflagellate Cysts in the Bohai Sea, China

2012 ◽  
Vol 47 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Wang Yan ◽  
Huang Lin ◽  
Gu Haifeng ◽  
Li Shuang ◽  
Li Shaoshan
Keyword(s):  
Species Diversity ◽  
Geographical Distribution ◽  
Bohai Sea ◽  
Dinoflagellate Cysts ◽  
The Bohai Sea

scholarly journals Storm Surges in the Bohai Sea: The Role of Waves and Tides

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1509
Author(s):  
Yuanyi Li ◽  
Huan Feng ◽  
Guillaume Vigouroux ◽  
Dekui Yuan ◽  
Guangyu Zhang ◽  
...  
Keyword(s):  
Storm Surge ◽  
Bohai Sea ◽  
Storm Surges ◽  
Wave Force ◽  
Laizhou Bay ◽  
Bohai Bay ◽  
Coastal Regions ◽  
The Bohai Sea ◽  
Tidal Phase ◽  
Set Up

A storm surge is a complex phenomenon in which waves, tide and current interact. Even though wind is the predominant force driving the surge, waves and tidal phase are also important factors that influence the mass and momentum transport during the surge. Devastating storm surges often occur in the Bohai Sea, a semi-enclosed shallow sea in North China, due to extreme storms. However, the effects of waves on storm surges in the Bohai Sea have not been quantified and the mechanisms responsible for the higher surges that affect part of the Bohai Sea have not been thoroughly studied. In this study, we set up a storm surge model, considering coupled effects of tides and waves on the surges. Validation against measured data shows that the coupled model is capable of simulating storm surges in the Bohai Sea. The simulation results indicate that the longshore currents, which are induced by the large gradient of radiation stress due to wave deformation, are one of the main contributors to the higher surges occurring in some coastal regions. The gently varying bathymetry is another factor contributing to these surges. With such bathymetry, the wave force direction is nearly uniform, and pushes a large amount of water in that direction. Under these conditions, the water accumulates in some parts of the coast, leading to higher surges in nearby coastal regions such as the south coast of the Bohai Bay and the west and south coasts of the Laizhou Bay. Results analysis also shows that the tidal phase at which the surge occurs influences the wave–current interactions, and these interactions are more evident in shallow waters. Neglecting these interactions can lead to inaccurate predictions of the storm surges due to overestimation or underestimation of wave-induced set-up.

Molecular characterization of harmful algal blooms in the Bohai Sea using metabarcoding analysis

Harmful Algae ◽  
2021 ◽  
Vol 106 ◽  
pp. 102066
Author(s):  
Hailong Huang ◽  
Qing Xu ◽  
Kate Gibson ◽  
Yang Chen ◽  
Nansheng Chen
Keyword(s):  
Molecular Characterization ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Bohai Sea ◽  
The Bohai Sea

scholarly journals Nitric oxide (NO) in the Bohai Sea and the Yellow Sea

2019 ◽  
Vol 16 (22) ◽  
pp. 4485-4496 ◽  
Author(s):  
Ye Tian ◽  
Chao Xue ◽  
Chun-Ying Liu ◽  
Gui-Peng Yang ◽  
Pei-Feng Li ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Surface Layer ◽  
Yellow Sea ◽  
Bohai Sea ◽  
Limit Of Detection ◽  
Bottom Layer ◽  
The Yellow Sea ◽  
The Bohai Sea ◽  
Significant Difference ◽  
Average Flux

Abstract. Nitric oxide (NO) is a short-lived compound of the marine nitrogen cycle; however, our knowledge about its oceanic distribution and turnover is rudimentary. Here we present the measurements of dissolved NO in the surface and bottom layers at 75 stations in the Bohai Sea (BS) and the Yellow Sea (YS) in June 2011. Moreover, NO photoproduction rates were determined at 27 stations in both seas. The NO concentrations in the surface and bottom layers were highly variable and ranged from below the limit of detection (i.e., 32 pmol L−1) to 616 pmol L−1 in the surface layer and 482 pmol L−1 in the bottom layer. There was no significant difference (p>0.05) between the mean NO concentrations in the surface (186±108 pmol L−1) and bottom (174±123 pmol L−1) layers. A decreasing trend of NO in bottom-layer concentrations with salinity indicates a NO input by submarine groundwater discharge. NO in the surface layer was supersaturated at all stations during both day and night and therefore the BS and YS were a persistent source of NO to the atmosphere at the time of our measurements. The average flux was about 4.5×10-16 mol cm−2 s−1 and the flux showed significant positive relationship with the wind speed. The accumulation of NO during daytime was a result of photochemical production, and photoproduction rates were correlated to illuminance. The persistent nighttime NO supersaturation pointed to an unidentified NO dark production. NO sea-to-air flux densities were much lower than the NO photoproduction rates. Therefore, we conclude that the bulk of the NO produced in the mixed layer was rapidly consumed before its release to the atmosphere.

Sign in / Sign up

Export Citation Format

Share Document