Surface Water Flood Maps (FRM_FH_SURFACE_WATER_VELOCITY_M)

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.本次公开的地表洪水概率分级如下： - 高概率：重现期10年 - 中概率：重现期200年 - 低概率：叠加基于英国气候预测2009（UKCP09）2080年代高排放情景的气候变化影响的200年一遇事件。 本次地表洪水灾害图谱包含以下可获取内容： - 淹没范围 - 淹没水深 - 适宜场景下的洪水流速。流速的展示需满足特定条件：需综合评估输入数据的可信度、建模方法与影响效应，当前流速以四个等级区间的形式呈现。 本数据集采用的气候变化情景，基于英国气候预测2009（UKCP09）针对2080年代高排放情景下的95%分位数预测结果设定。本次选取中、低概率洪水事件，旨在与苏格兰规划政策所采用的重现期标准保持一致；而高概率事件的选取，则为了贴合近数十年来实际观测到的洪水事件特征。