River Flood Maps (FRM_FH_RIVER_VELOCITY_M_CC)

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.本批洪水危险地图（flood hazard maps）是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》规定的法定发布职责而编制的。 本批地图展示了海洋、河流及地表径流引发的洪水风险区域。 针对河流洪水，提供以下不同概率等级的风险场景： - 高概率：10年一遇重现期（return period） - 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（UKCP09）高排放情景的200年一遇气候变化修正场景 河流洪水危险地图将（如可获取相关数据则展示）以下信息： - 洪水淹没范围（flood extent） - 洪水水深（flood depth） - 适宜场景下的洪水流速（flood velocities） 本次气候变化情景依据英国气候预测2009（UKCP09）针对2080年代高排放场景的95百分位（95%ile）预测结果设定。 流速信息仅在适宜场景下予以展示，其判定依据为输入数据可信度、建模方法及影响评估结果。 当前流速被划分为四个等级之一。中、低概率洪水场景的选取参考了苏格兰规划政策（Scottish Planning Policy）中采用的重现期标准，而高概率场景则选取近数十年间实际观测到的典型洪水事件作为参照依据。