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本文对波罗的海1981～1994年间的降水和蒸发率进行了分析。基于可获得的天气资料以二维目标分析方法进行插值。得到了网格点的降水率数据。蒸发率通过一个海洋模型计算得到。这一模型将波罗的海处理为13个具有高垂向分辨率的亚流域。海面温度和海冰由计算得到,并根据温度和冰图信息进行了全面校检。在这一模型中,潜热通量由总体公式参数化计算得到。蒸发率通过潜热的计算值得到,而海冰又使蒸发率变小,假定海冰的蒸发可以忽略。从长期来看,降水和蒸发率之间的差异是正值,这说明大气补充淡水到波罗的海中。对于1981～1994年这一段时间来说。来自于大气的淡水总输入量平均为1986m~3/s。这一数值比河流的总径流量小,但同涅瓦河的贡献几乎一样大。因此。大气的淡水输入是波罗的海淡水平衡的重要来源。同虚拟的无冰的波罗的海相比。将冰考虑在内能将研究时段内大气淡水输入量的长期均值提高26%(通过使蒸发降低8%)。波罗的海的降水和蒸发具有较大的年际、季节和地区变化。
This paper analyzes the precipitation and evaporation rates in the Baltic Sea from 1981 to 1994. Interpolation is based on available weather data using two-dimensional object analysis. Got the precipitation data of grid point. Evaporation rate is calculated from an ocean model. This model treats the Baltic Sea as 13 sub-basins with high vertical resolution. Sea surface temperature and sea ice are calculated and fully calibrated based on temperature and ice map information. In this model, the latent heat flux is calculated by the general formula. The evaporation rate is obtained from the calculated latent heat, which, in turn, reduces the evaporation rate, assuming evaporation of sea ice is negligible. In the long run, the difference between precipitation and evaporation rates is positive, indicating that the atmosphere replenishes freshwater into the Baltic Sea. For the period 1981-1994. The average fresh water input from the atmosphere is 1986m ~ 3 / s. This value is smaller than the total runoff of the river, but it is almost as large as that of the Neva. therefore. Atmospheric freshwater input is an important source of freshwater balance in the Baltic Sea. Compared with the virtual ice-free Baltic Sea. Taking ice into account increases the long-term mean of atmospheric freshwater input over the study period by 26% (by reducing evaporation by 8%). The Baltic Sea has large interannual, seasonal and regional variations in precipitation and evaporation.