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.本次地表洪水（surface water flooding）可使用以下概率等级： - 高概率：重现期（return period）10年 - 中概率：重现期200年 - 低概率：重现期200年叠加2080年代英国2009年气候预测（UKCP09）高排放情景下的气候变化影响。 地表洪水灾害地图将展示（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可信度、建模方法与影响效应进行判定，目前分为四个等级呈现。 本研究采用的气候变化情景基于英国2009年气候预测（UKCP09）中2080年高排放情景下95%分位数预测结果。中、低概率洪水事件的选取遵循苏格兰规划政策中采用的重现期标准，而高概率事件则选取近数十年实际观测到的典型洪水事件作为参考依据。