荷兰气候学家A·H·Thiessen提出了一种根据离散分布的气象站的降雨量来计算平均降雨量的方法，即将所有相邻气象站连成三角形，作这些三角形各边的垂直平分线，于是每个气象站周围的若干垂直平分线便围成一个多边形。(Holland climate scientist A H Thiessen proposed a new method to calculate the average rainfall according to the discrete distribution of meteorological stations rainfall, meteorological stations are all adjacent triangles, as these triangles on each side of the perpendicular bisector)