River Flood Maps (FRM_FH_RIVER_VELOCITY_L)

These maps have been produced to meet SEPA’s duty to publish flood hazard maps as set out in the Flood Risk Management (Scotland) Act 2009. The maps show where there is a risk of flooding from the sea, from rivers and from surface water.The following probabilities are available for river flooding: - High - 10 year return period - Medium - 200 year return period - Low - 1000 year return period and 200 year return period plus climate change using the UKCP09 high emissions scenario for the 2080s.The river hazard maps show (where available): - Flood extent - Flood depth - Flood velocities where appropriate. The climate change scenario has been defined by United Kingdom Climate Projection 2009 (UKCP09) predictions for 2080 high emissions 95%ile predictions. 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 bandsMedium 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.本批地图系为履行苏格兰环境保护署（SEPA）依据《2009年洪水风险管理（苏格兰）法案》所规定的发布洪水危险地图的法定职责而编制。本系列地图展示了受海洋、河流及地表水引发的洪水风险的区域。 针对河流洪水，提供以下概率等级的成果： - 高概率：10年重现期 - 中概率：200年重现期 - 低概率：1000年重现期，以及结合2080年代英国2009年气候预测（UKCP09）高排放情景的气候变化影响后的200年重现期洪水。 河流危险地图将在数据可用时展示以下内容： - 洪水淹没范围 - 洪水水深 - 适用情况下的洪水流速。 本气候变化情景系基于英国2009年气候预测（UKCP09）针对2080年高排放情景的95%分位数预测结果设定。流速数据仅在适用情况下予以展示，其判定依据为输入数据可靠性、建模方法及影响程度，目前分为四个等级进行表征。 中概率与低概率洪水事件的选取标准系为与苏格兰规划政策中采用的重现期规范保持一致，而高概率洪水事件的选取则反映了近数十年来已观测到的实际洪水灾情。