River Flood Maps (FRM_FH_RIVER_VELOCITY_DIRECTION_H)

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（Scottish Environment Protection Agency, 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性地图的法定职责而编制。该类地图展示了受海洋、河流及地表水引发洪水风险的区域。针对河流洪水，提供以下概率等级的场景： - 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，以及结合2080年代英国气候预测2009（United Kingdom Climate Projection 2009, UKCP09）高排放情景的200年一遇重现期气候变化影响场景。 河流危险性地图（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。 本次气候变化情景基于英国气候预测2009（UKCP09）针对2080年高排放情景的95%分位数预测结果定义。洪水流速数据（适宜场景下）的呈现需综合考量输入数据置信度、建模方法与影响评估结果进行确定，目前按四个等级进行展示。本次选取中、低概率洪水事件的重现期标准，以契合苏格兰规划政策中采用的重现期规范；而高概率场景的选取则反映了近数十年来已观测到的实际洪水事件特征。