| With the rapid development of human society,the consumption of mineral resources is also increasing day by day,however,the total amount of global mineral resources is limited,and with people’s long-term exploitation and consumption of land mineral resources have been nearly depleted.The ocean contains a large variety of rich mineral resources,which can provide sufficient power for human development.Although there are large reserves of marine mineral resources,most of the minerals are often hidden in thousands of meters deep under the sea,and deep-sea mining faces problems such as high cost and insufficient reliability of key equipment,but more importantly,people lack sufficient research on the extreme environmental conditions in the deep-sea mining process.In this paper,using the 22,821 km2 mining area(contract ID:CMMPMN1)in the Clarion-Clipperton Zone(CCZ)of the Pacific Ocean,which has been acquired by China,as the main research area,statistical analysis of ERA-5 wind field data and FIO-COM model current data during the three years from 2014 to 2016,integrated Lagrangian particle tracking The numerical simulation results were used to study the sea-air dynamics environment and material transport patterns in the Chinese deep-sea mining contract area in the North Pacific Ocean,and the following conclusions were drawn:(1)In the whole North Pacific region,the wind speed is higher at low latitudes,mostly maintained at 6-10 m/s throughout the year,and the wind direction is mainly n ortheast;the wind speed is smaller at middle latitudes,mostly maintained at 0-4 m/s t hroughout the year;the wind speed varies seasonally at high latitudes,with higher win d speed in winter and spring,and lower wind speed in summer and autumn,and the w ind direction is mainly westerly.In the North Pacific Ocean,the current velocities are higher in the southern low-latitude area near the equator and in the northwestern area near the Sea of Japan throughout the year,and the current velocities in the northern ar ea are generally lower than those in the south.At the same time,there are many eddies of different sizes in the North Pacific Ocean,and the size and location of the eddies v ary significantly with time.(2)The wind direction in the Chinese deep-sea mining contract area is mainly in northeast direction throughout the year,and the wind speed varies seasonally,the win d speed in the first,second and fourth quarters of the year is at the high value through out the year,the average wind speed is between 6.3-9.3 m/s,and the wind direction is mainly in northeast direction;from July to October the wind speed drops steeply to th e low value throughout the year,and at the same time the wind direction becomes non-directional.(3)The sea surface current velocity and direction in the Chinese deep-sea mining contract area have obvious seasonal variation characteristics.From January to June,t he direction of sea surface currents in the mining area basically remains unchanged,p ointing to the northwest,and the velocity is maintained between 0.1 and 0.3 m/s;from July to September,the direction of sea surface currents changes from east to west to west to east,and the velocity drops significantly from July to August,and reaches the lowest value of 0.05 m/s in August,and then increases slightly in September;from Oc tober to December,the direction of currents gradually changes from west to east to no rth,and the velocity increases slightly.From October to December,the flow direction gradually shifts from west to east to north,and the flow velocity gradually increases.At the same time,the velocity of the vertical current decreases with increasing depth,and the flow direction appears spiral.(4)Using the calculated mining window as the calculation time and setting differ ent points in the mining area as the starting point for particle tracking,the results sho w that the direction and distance of particle transport are mainly related to latitude at t he same depth;meanwhile,as the depth increases,the distance of particle transport de creases significantly and the direction of transport changes greatly. |
