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.本批地图的制作旨在履行苏格兰环境保护局（Scottish Environment Protection Agency, SEPA）根据《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（flood hazard map）的法定职责。本批地图展示了海洋、河流及地表水引发的洪水风险区域。 针对河流洪水，本数据集提供以下概率等级的洪水风险场景： - 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，以及基于英国2009年气候预估（UKCP09）2080年代高排放情景的200年一遇气候变化修正场景。 河流洪水危险地图将展示（如可获取相关数据）： - 洪水淹没范围 - 洪水水深 - 适宜场景下的洪水流速。 本次采用的气候变化情景基于英国2009年气候预估（UKCP09）针对2080年代高排放情景的95百分位（95%ile）预测结果。 流速信息仅在适宜相关场景时提供，其是否展示需综合考量输入数据可信度、建模方法及影响效果而定。流速等级目前分为四个分级。本次选取中、低概率洪水场景以匹配苏格兰规划政策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。