ettfement and church 3.The new towr 4.Commercia Ship tonnage 5 Modem sea terrninal Time The rapid uplift of the land along the coast of Norrland,80-90cm in 100 years,made it necessary to move ports down to deeper water.The increasing draught of modern ships has speeded up this process. 海岸地面抬升(1cmla)促使港口向河流下游深水处迁移，只吨 位（吃水深度）的增加亦加速了该过程一港口城市形成海岸地面抬升(1cm/a)促使港口向河流下游深水处迁移, 船只吨 位(吃水深度)的增加亦加速了该过程—港口城市形成