The Risk Simulation And Environmrent Sensitive Area Nearby Effects Of Oil Spill In Binhai Offshore

The ocean is an indispensable puzzle of the Earth’s ocean system,with rich natural resources and have a vital role in human social activities.In recent years,with the rapid development of the marine field,the ocean is facing a huge threat of environmental pollution,risk of oil spill accidents occured frequently and in the marine environment,marine ecology and regional socio-economic activities have significant short-term or long-term adverse effects.The coastal seas of northern Jiangsu are located in the southern part of the Yellow Sea.The dynamic factors of water environment are complicated and there are many environmental sensitive areas.In the past,the area of marine engineering projects is relatively small,economic lag,the ecosystem is relatively complete,are relatively undeveloped seas.With the development of economy,during the 2011-2020 period,there will be a large number of offshore wind farms as a typical representative of the coastal marine engineering planning projects,its have a lot of oil pollution risk during development and application.once the oil spill occurs,it will have an immeasurable impact on the surrounding marine environment,marine aquaculture and coastal environment sensitive areas,and the harmfulness will be far more than other areas.Therefore,it is of great theoretical and practical value to predict the potential risk of oil spill and evaluate the impact of environmental sensitive area.In this paper,take the relative intensive and typical Marine engineering of Jiangsu coastal areas as the study area,to the maritime ship as a source of risk.The ocean dynamic model and the sea oil spill risk prediction model are established by using the MIKE 21 model system,and analyze the impact of oil spill pollution for environment sensitive areas,the specific content including:(1)Using SMS software and MIKE21_FM HD module to establish a 2-D ocean dynamic model of Binhai area based on the flexible mesh,the characteristics of the current are analyzed and the reliability of the model is verified according to the measured hydrological data(tide,velocity and flow).The results show that the calculated value is consistent with the overall change of the measured value,and therelative deviation is less than 8%.The actual ocean current characteristics of the engineering sea area can be accurately reflected and can provide reliable surface driving conditions for the oil spill risk prediction module.(2)Based on the hydrodynamic basis data provided by the ocean dynamic model,Using MIKE21/3 oil spill analysis module(SA)to establish a oil spill risk prediction model of Binhai area,and Simulating the power and non-power process of oil spill at sea(transport,expansion and weathering).Considering the scene combination of different tide moment(high tide,ebb)and different wind conditions(static wind,summer dominant wind,winter dominant wind and unfavorable wind),the typical oil particle drift trajectories,diffusion range and concentration distribution,sweep area under different simulated scenarios are analyzed.The results show that the diffusion range and trajectories of oil particles under different wind conditions,oil spill occurrences and tidal flow field are obviously different.The wind field has a decisive impact,tidal field second only to it,When the two directions are consistent,there is a superposition effect,otherwise the wind condition plays a leading role.The Sweep area of oil slicks increased with time of oil spill,and it get a maximum 626.89km~2 in the summer monsoon of ebb tide;The amount of residual oil decreaseed with time,and reached an average of 66.07% after 72 hours.(3)Based on the results of oil spill risk prediction and the distribution of environment sensitive areas,predicted and analyzed the pollution situation of the main environmental sensitive targets within 72 hours.The results showed that oil spill pollution had the same effect on Yancheng Nature Reserve,shoreline,important economic fish,mariculture area and coastal tourist area,which nature reserve and shoreline most affected,mariculture area and coastal tourist area second only to it,important economic fish are the least affected.The earliest time affected by the oil spill for the northern of Yancheng Nature Reserve was 16 hours,and the southern was 30hours;the earliest affected time along the coastline was 20 hours;“Three field one channel” without being affected by oil in 72 hours;the earliest affected time for the mariculture area was 18 hours;the earliest affected time for the coastal tourist area was28 hours.