Numerical modelling of large-scale circulation in Lakes Onega and Ladoga

Large-scale circulation in Onega lake and Ladoga lake was modelled numerically, with particular attention to the temporal variability of current during periods of several days. Typical circulation patterns inferred from the results reflected the existence of different dynamic regimes in the 2 lakes, namely forced and free-circulation regimes. The barotropic circulation patterns in Ladoga lake were found, with particular emphasis on the prevailing winds from west to south-east. The bottom relief of the lake produced an asymmetry in the wind-induced double-gyre circulation pattern. The pattern of cyclonic and anti-cyclonic circulation cells was determined in relation to the wind direction.