【摘要】 在中国陆架海区调查获得的CTD资料表明,陆架区的水文要素垂直结构大都可以理想化为三层垂直结构模式:上均匀层、跃层和下均匀层。提出了一种用3条线段构成的拟阶梯函数拟合水文要素垂直剖面的方法,利用最小二乘法求出2个拐点的位置,即温跃层的上界和下界,取2个拐点的联线的斜率作为温跃层强度。对陆架海区各种不同的温度要素垂直结构形态整理归纳,分为正跃层、逆跃层、单方向多跃层和正逆跃层混合4种类型。各种类型均可按照一个或多个拟阶梯函数进行最小二乘拟合来获得温跃层的特征量。更多还原

【Abstract】 It is shown from the CTD data collected in Chinese shelf sea area that most of vertical structures of hydrographic elements can be idealized as a　3-layer structure pattern, namely, upper homogeneous layer, thermocline and lower homogeneous layer. In this paper, the quasi-step function approximation method is propsed, i.e., a quasi-step function composed of 3 line segments is used to fit the vertical profile of hydrographic element, the least square method is used to get the two inflection point positions, the upper and lower thermocline bounds, and the slope of the line connecting the two inflection points is taken as the thermocline intensity. The vertical temperature structures in the shelf sea area can be summarized as 4 patterns, positive thermocline, reverse thermocline, unidirectional multi-thermocline and mixed positive and reverse thermocline patterns, and the characteristic elements of different thermocline patterns can be calculated by the least squares fit of one or several quasi-step functions.更多还原