基于WOA13数据的北大西洋声传播分析

应用WOA13季节平均数据和BELLHOP模型,在季节、声源频率、声源深度和掠射角等因素确定的情况下,分析北大西洋冬季(1-3月)声道轴深度、最小声速值、表层声速值的分布,通过仿真计算研究选用位置点5 m深度声源的声传播规律:反转深度随纬度升高而降低,低纬度海岭东西两侧差别不大,15°N以北为西侧大于东侧。55°N以南海区可形成汇聚区波导,海岭西侧的汇聚区跨度大于海岭东侧,有混合层时还存在一定强度的表面波导,汇聚区处5 m、100 m和250 m接收深度上的传播损失差异较小,增益为7～19 dB,55°N以北海区则为有焦散结构的表面波导。以北大西洋35°N为界,以南以汇聚区波导探测有利,以北以表面波导探测有利。

Analysis of acoustic propagation in the North Atlantic Ocean based on WOA13 data

By using the seasonal average data of WOA13 and the BELLHOP model, under the circumstances of given factors of season, sound source frequency, sound depth and grazing angle, this essay analyzes the distribution of values corresponding toaxis of sound channel, minimal sound velocity, and surface sound velocity of the North Atlantic Ocean in winter (from January to March). It also studies the laws of acoustic propagation in 5 m depth in a chosen location in simulated calculation:reverse depth decreases with latitude increase, there is not too much difference between eastern and western sides of theoceanridge in low latitudes, and the west side is greater than the east side to the north of 15°N. Convergence zone can be formed to the southen sea areas of 55°N, the span of convergence zone in western side of the oceanridge is greater than that of the eastern side, there exists surface waveguide of certain intensity if mixed layer there is the mixed layer there, and in convergence zone, the difference of transmission loss in receiving depth of 5 m, 100 m and 250 m is small, and the gain was 7dB to 19 dB. In the sea areas to the north of 55°N exists surface waveguide with caustic structures. Based on the line of 35°N in the North Atlantic Ocean, to the south, the detection with convergence waveguide is better,and to the north,the detection with surface waveguide is better.