Surface Water Flood Maps (FRM_FH_SURFACE_WATER_VELOCITY_L)

The following probabilities are available for surface water flooding: - High - 10 year return period - Medium - 200 year return period - Low - 200 year return period plus climate change using the UKCP09 high emissions scenario for the 2080s.The surface water hazard maps show (where available): - Flood extent - Flood depth - Flood velocities where appropriate. Velocity is presented, where appropriate; this is determined by considering the confidence in input data, modelling method and impact. It is currently represented as one of four bandsThe climate change scenario has been defined by United Kingdom Climate Projection 2009 (UKCP09) predictions for 2080 high emissions 95%ile predictions. Medium and low probability flood events were selected for consistency with return periods used in Scottish Planning Policy, whereas the high probability was chosen as it is reflective of observed events experienced over the last few decades.本数据集包含以下地表水洪水概率等级： - 高概率：对应10年一遇重现期 - 中概率：对应200年一遇重现期 - 低概率：叠加气候变化影响的200年一遇情景，采用英国气候预测2009（UKCP09）高排放情景下2080年代的预测数据 地表水灾害地图将展示（如可获取）以下内容： - 洪水淹没范围 - 洪水水深 - 适宜场景下的洪水流速 流速的展示需结合输入数据置信度、建模方法与影响评估进行判定，当前将流速划分为四个等级之一。 本次气候变化情景基于英国气候预测2009（UKCP09）针对2080年高排放情景的95%分位数预测结果定义。中、低概率洪水事件的选取与《苏格兰规划政策》中采用的重现期标准保持一致，而高概率事件的选取则反映了近数十年间观测到的实际洪水事件特征。