We evaluated the thermocline spatial distribution in the longline fishing grounds of Thunnus albacares and Thunnus obesus in the Atlantic Ocean using Argo profile buoy data from 2007 to 2011.Based on those basic works,the monthly distribution maps of the upper boundary depth and its temperature,the lower boundary depth and its temperature of the thermocline were plotted.The topography of the upper boundary depth,temperature of the thermocline showed obvious seasonal variation,roughly in zonal striped distribution on the annual mode.The spatial distribution of the upper boundary depth of the thermocline is deep in winter while shallow in summer.From December to the next April,the upper boundary depth is higher than 80m to the north of 15°N,while lower than 50m to the south of 10°S.The opposite happens from June to October.The upper boundary temperature is above 27℃ in the equator zonal area,and the upper boundary temperature becomes lower from the equator to high latitude zonal area,till 20℃ and lower.The topography of the lower boundary depth and the temperature of the thermocline showed little seasonal variability on the annual mode.The high value shape of the lower boundary depth looks like a W,and the value is greater than 220m.The lower boundary depth is lower than 150m from the South American to the West Africa to the south of 25°S,extending to the coast of Angola and to 10°N in most the months of year.The lower boundary temperature is lower than 14℃ in equator zonal and higher than 15℃ in high latitude area.The thermocline thickness was large between 5°N and 15°N,and between 5°S and 15°S in the western Atlantic,ranging from 80 to 150m,but the distribution characteristics of winter and summer were opposite.The thermocline intensity was large between 5°S and 15°N,especially in the eastern Atlantic,ranging from 0.15 to 0.25℃/m.The analysis results reveal the spatial distribution seasonal characteristic of the thermocline in major longline tuna fishing ground of T.obesus and T.albacares in the tropical Atlantic Ocean which provide reference to longline production operation of tuna,and suggest that cast hook depth for T.albacares and T.obesus in the night should be around the upper boundary of the thermocline depth,and the cast hook depth for longline T.albacares in the day near the lower boundary depth of the thermocline,while the T.obesus cast hooks should be set deeper than that of T.albacares.%采用2007 ～2011年Argo浮标剖面温度资料研究了大西洋黄鳍金枪鱼(Thunnus albacares)和大眼金枪鱼(Thunnus obesus)延绳钓主要作业渔场温跃层的时空变化特征.研究结果表明热带大西洋黄鳍金枪鱼、大眼金枪鱼延绳钓主要作业渔场温跃层的上界深度和温度存在着明显的季节性变化.温跃层上界深度呈现出冬深夏浅的季节性变化特征,大致呈纬向带状分布,12月至翌年4月份,15°N以北海域温跃层上界深度超过80 rn,同期10°S以南海域的多低于50 m；6～10月份的则相反.在赤道纬向区域温跃层上界温度在27℃以上,往南北两侧30°区域温度值依次递减至20℃及以下.温跃层下界深度和温度没有明显的季节性变化.温跃层下界深度高值区域的空间分布呈现“W”形状,深度值在220 m以上.在25°S以南,从南美洲到非洲西沿岸海域并延伸到安哥拉外海,以及10°N非洲西海岸外海,在1a中的大部分月份里,温跃层下界深度浅于150 m.在15°N以北和15°S以南区域下界温度大于15℃,在这之间的纬向区域下界温度低于14℃.全年在大西洋西部的5 °～ 15°N和5 °～15°S区域的温跃层厚度最大,在80～150 m之间,冬季和夏季呈现相反的分布特征；温跃层强度高值在5°S～ 15°N纬向区域,尤其是大西洋东部,介于0.15 ～ 0.25℃/m之间.根据文中揭示的大西洋金枪鱼延绳钓主要作业渔场区温跃层的时空变化特征,作者建议晚上大眼金枪鱼和黄鳍金枪鱼投钩深度应该在温跃层上界深度分布的附近水域；白天捕捞黄鳍金枪鱼投钩深度应该在温跃层下界深度分布的水域附近,大眼金枪鱼投钩深度要比黄鳍金枪鱼的更深.
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