首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Wind forced circulation and sediment disturbance in a temperate lake
Authors:M Gibbs  J Abell  D Hamilton
Institution:1. National Institute of Water and Atmospheric Research Ltd, Hamilton, New Zealand;2. Environmental Research Institute, University of Waikato, Hamilton, New Zealand
Abstract:Meteorological forcing on the surface of a lake can generate mixing and transport processes that alter water quality. This study examined how meteorological forcing affected water currents in Lake Rotorua—a large, shallow, temperate, polymictic lake—during a period of sustained vertical mixing and strong winds. Acoustic Doppler current profiler (ADCP) measurements were recorded at two sites and a hydrodynamic model (ELCOM) was used to simulate water movement over the period of ADCP measurements. Model simulations show circulation patterns in Lake Rotorua are strongly influenced by the topography of the lake and, to a lesser extent, the catchment, with little variation in currents with depth during winter mixing. Northeasterly winds produced a clockwise circulation around the mid-lake island with a second anticlockwise gyre between the island and the western shore. This circulation pattern is consistent with topographic gyres found in other large lakes. A shift to a weaker southwesterly wind caused these circulation patterns to reverse direction over a period of c. 6?h, with a weak secondary gyre also occurring within the main anticlockwise circulation. The effect of this circulation pattern on the resuspension of sediment and thus potential in-lake phosphorus control strategies is considered.
Keywords:Bed stress  ELCOM  lake currents  Lake Rotorua  measurements  modelling  New Zealand
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号