ВОЗМОЖНОСТИ ДОЛГОСРОЧНОГО ПРОГНОЗА ПРИТОКА ВОДЫ В БУРЕЙСКОЕ ВОДОХРАНИЛИЩЕ

Development of the long-range inflow forecast system to the Bureyskaya reservoir, carried out in 2008-2010 at the request of the RusHydro Company, is presented. Estimations were performed based on terms of statistical probabilities with about month-quarter lead-time. Considering features of extreme flow formation processes and wetness of territory, the focus was warm period (June-September), which is known for its heavy rainfall events. During the investigations there were examined the dynamic-stochastic approach, based on the deterministic hydrological model with using of meteorological characteristics ensemble by weather generator as input, and inflow forecast to the reservoir in terms of probability curve based on multidimensional stochastic modeling. The project included two main stages: development of precipitation and temperature forecast method with month-six months lead-time; development of inflow probabilistic forecast method with month-quarter lead-time based on expected values of precipitation and temperature. Methods pretesting demonstrated reasonable inflow forecast reliability (about 90%), mean absolute deviation of expected inflow volume from observed is 23-28% relative to mean value. Driven by the developed framework, it was forecasted precipitation sums and reservoir inflow at the individual seasons. By comparing of measured and forecasted values, it was made a conclusion, that accuracy of the forecast scheme is satisfactory. The mean values of the precipitation forecast reliability is 75-80%. Forecasted reservoir inflow in 2009 and 2010 is assessed as close to a measured one.