2024-03-28T15:40:40Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/476472022-11-17T02:08:08Zhdl_2115_47646hdl_2115_47366hdl_2115_33096Floating ice platform for winter observations in freezing lakes and coastal watersShirasawa, KunioLeppäranta, Matti450An automatic observation float has been designed, tested and utilized for wintertime investigations in lakes and coastal waters. The float can be deployed in a lake during the open water season, so that it is capable to collect data continuously throughout the period of freeze-up and further on during the ice season. The float is anchored to the bottom so that it should be stable in the freeze-up period. The instrumentation includes a 2-m mast for measurements of the atmospheric boundary layer and radiation balance, thermistor strings and PAR sensors down from the water surface for measurements in ice and water, and an independently anchored current meter and CTD sensor. The float has been utilized in several lakes in Finland and in Santala Bay in the Baltic Sea in 1999–2011 with very good results. The data have been used for investigations of the lake heat fluxes, ice formation and melting, and light transfer in the snow–ice–water system. The data have also served as the calibration and validation data in the development of an advanced thermodynamic lake ice model including the layers of snow, slush, snow-ice and congelation ice. In addition, they have been utilized in the modelling the winter circulation in an ice-covered lake. This measurement system will be a suitable platform in further collaborative physical–biological investigations of freezing lakes and landfast ice in coastal regions.北方圏の環境研究に関するシンポジウム. 2011年10月31日(月). 北海道大学学術交流会館 小講堂. Northern Environmental Research Symposium (Hokkaido-Finland Days: A Bridge for Northern Cooperation). Monday, 31 October, 2011. Hokkaido University Conference Hall.Presentationapplication/pdfhttp://hdl.handle.net/2115/47647https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/47647/1/1-1_shirasawa.pdf2011-10-31engpublisher