River Flood Maps (FRM_FH_RIVER_VELOCITY_M)

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.本批洪水灾害地图（flood hazard maps）的编制，旨在履行苏格兰环境保护局（Scottish Environment Protection Agency，SEPA）依据《2009年洪水风险管理（苏格兰）法案》所承担的洪水灾害地图发布义务。本地图展示了受海洋、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灾害场景： - 高概率：10年一遇重现期 - 中概率：200年一遇重现期 - 低概率：1000年一遇重现期，以及基于2080年代英国气候预测2009（UKCP09）高排放情景下的200年一遇重现期叠加气候变化影响的场景 河流灾害地图将展示以下内容（如可获取）： - 洪水淹没范围 - 洪水水深 - 适宜场景下的洪水流速 本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。流速信息仅在适宜场景下予以展示；其展示与否需结合输入数据可信度、建模方法及影响评估综合判定，目前分为四个等级进行呈现。 本次选取中、低概率洪水场景，以契合苏格兰规划政策中采用的重现期标准；而高概率场景的选取则基于近数十年间实际观测到的洪水事件。