6533b839fe1ef96bd12a652c
RESEARCH PRODUCT
Modelling circulation in an ice-covered lake
Matti LeppärantaKunio ShirasawaTimo HuttulaB. V. ArkhipovKalevi SalonenMerja PulkkanenV. V. Solbakovsubject
0106 biological sciences010504 meteorology & atmospheric sciences010604 marine biology & hydrobiologyFlow (psychology)lcsh:QE1-996.5SedimentForcing (mathematics)Atmospheric sciences01 natural sciencesPrinceton Ocean ModelCurrent (stream)lcsh:GeologyCirculation (fluid dynamics)Heat fluxhydrodynamic modelling13. Climate actionAnticycloneClimatologyGeneral Earth and Planetary Sciences14. Life underwaterLake Pääjärvi.Geologycurrents0105 earth and related environmental sciencesWater Science and Technologydescription
In deep ice-covered lakes with temperatures below 4 °C the heat flux from the bottom sediment results in a horizontal density gradient and a consequent flow along the bottom slope. Measurements in Lake Paajarvi, Finland, show a stable temperature field where a heat gain through the bottom and a heat loss through the ice nearly balance each other. The circulation is thermal with low velocities (less than 1.5 cm s -1 ). We used the 3D hydrodynamic Princeton Ocean Model as a tool to simulate the water circulation and the temperature distribution under the ice. The model forcing was based on field temperature measurements. The model simulations suggest that in midwinter the velocity field of the upper water layers is anticyclonic while that of deep layers is cyclonic. Comparison with current measurements at one site showed good agreement between the modelled and observed results. On the basis of the modelled results it is possible to better understand the distributions of some micro- organisms and the accumulation of oxygen depleted waters in the deepest part of the lake.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-12-01 | Estonian Journal of Earth Sciences |