00000nam 2200000zi 4500 9.871039 CaOODSP 20241203113647 m o d f cr ||||||||||| 190403s1995 onca #ot f000 0 eng d CaOODSP eng rda CaOODSP n-cn--- En13-5/95-42E-PDF Helsten, M. A., author. Modelling polynya formation by vertical jet flow in lakes / by: M. Helsten, P. Hamblin, R. Baddour. [Burlington, Ontario] : Environment Canada, Water Science and Technology Directorate = Environnement Canada, Direction générale des sciences et de la technologie, eau, [1995] 1 online resource (13 unnumbered pages) : illustrations. text txt rdacontent computer c rdamedia online resource cr rdacarrier NWRI contribution ; 95-42 Digitized edition from print [produced by Environment and Climate Change Canada]. Includes bibliographical references. "When ice cover on mid-latitude lakes prevents the replenishment of stored dissolved oxygen, which has been depleted by biological demand and reduced oxygen production in the winter, massive fish kills have been reported. The water quality in an ice-covered, eutrophic lake can be improved by creating an ice opening through the use of a flow developer. This ice opening, or polynya, provides a large area of exposed water through which the lake can be naturally aerated. The flow developer circulates warmer water from the bottom of the lake, and uses this flow to open and maintain the polynya throughout the winter months. A previous field study has shown that it is important that the circulation causing the ice free patch is minimal under the ice to prevent excessive heat loss. Thus, any flow development system would be optimized from this viewpoint as well as the operating cost. This study examines the performance of a submerged flow-developer which pumps water from a lake bottom vertically onto the underside of the ice cover"--Abstract. gccst Lakes gccst Ice gccst Water management Hamblin, P. F., author. Baddour, Ralph E., 1976- author. Canada. Environment Canada. National Water Research Institute (Canada) NWRI contribution ; 95-42. (CaOODSP)9.844121 PDF 1.38 MB https://publications.gc.ca/collections/collection_2019/eccc/en13-5/En13-5-95-42-eng.pdf