Surface Water Flood Maps (FRM_FH_SURFACE_WATER_VELOCITY_H)

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.本次地表洪水灾害具备如下概率等级及对应情景： - 高概率：重现期10年 - 中概率：重现期200年 - 低概率：基于2080年代英国2009年气候预测（UKCP09）高排放情景叠加气候变化影响的200年一遇洪水情景 地表洪水灾害风险图涵盖（如可获取的情况下）以下内容： - 洪水淹没范围 - 洪水水深 - 洪水流速（酌情展示）。流速的展示需结合输入数据可信度、建模方法与影响评估综合判定，当前共划分为四个等级。 本数据集所采用的气候变化情景，基于英国2009年气候预测（UKCP09）中2080年代高排放情景下95%分位数预测结果。 中、低概率洪水情景的选取契合《苏格兰规划政策》中采用的重现期标准，而高概率情景的选取则贴合近数十年间实际观测到的洪水事件特征。