The most severe large-scale flood on record occurred on the Amur River and its main tributaries (the Songhua, the Zeya, and the Bureya Rivers) in August-early September 2013. Prolonged heavy rainfalls over the vast territory of the Amur River basin produced the flood during the summer of 2013.
During the flood monitoring, it was noted that observed precipitation data from the Amur River observational network had not represented areal precipitation over drainage basins of the Amur River and its tributaries well enough. Therefore, operational Weather Research and Forecasting (WRF)-Advanced Research WRF (WRF-ARW) model with grid distance of 15 km was applied for prediction of areal precipitation over that territory.
The results of the simulation were compared with observed precipitation and water level data from the outlet points of partial drainage basins of the Amur River in June-September 2012 and 2013 to discuss the possibility of using numerically simulated precipitation in hydrological applications related to the Amur River basin. During the summer months of those years, an extreme flood occurred in 2013, while the hydrological situation was normal in 2012 on the Amur River.
The results of the comparison show that the amount of precipitation simulated on grid points of partial basins of the Amur River and its tributaries are in better agreement with major flood peaks than precipitation data obtained from the observational network. Additionally, if the five-day total areal precipitation averaged over the territory of a partial drainage basin exceeds 20 mm, the water level on an outlet point of a partial drainage basin of the Amur River monotonically increases independent of any variations of precipitation at an amount above the 20 mm value.
2016 by Meteorological Society of Japan