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.本数据集提供了以下地表洪涝的概率分级及对应情景： - 高概率：10年一遇重现期 - 中概率：200年一遇重现期 - 低概率：2080年代采用英国气候预测2009（UKCP09）高排放情景叠加气候变化影响的200年一遇重现期情景。 地表洪涝灾害风险图（如可获取）将展示以下内容： - 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可信度、建模方法及影响效应进行综合判定，目前将其划分为四个等级进行呈现。 本研究采用的气候变化情景基于英国气候预测2009（UKCP09）针对2080年高排放情景下95百分位的预测结果。中、低概率洪涝事件的选取参考了《苏格兰规划政策》中采用的重现期标准，而高概率事件的选取则贴合近数十年来实际观测到的洪涝事件特征。