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.本批洪水危险地图的编制，旨在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》所规定的洪水危险地图发布义务。本批地图展示了海洋、河流及地表水引发洪水风险的区域。针对河流洪水，现有以下概率分级的区划结果： - 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2080年代采用英国气候预测2009（UKCP09）高排放情景的200年一遇重现期叠加气候变化影响的场景。河流洪水危险地图将展示（如可获取）以下信息： - 洪水淹没范围 - 洪水水深 - 适用场景下的洪水流速。本研究所采用的气候变化情景，依据英国气候预测2009（UKCP09）针对2080年高排放情景下的95百分位预测结果设定。流速信息仅在适用场景下提供，其生成需综合考量输入数据、建模方法及影响评估的可信度，目前分为四个等级进行展示。选取中、低概率洪水事件，是为了与苏格兰规划政策中采用的重现期标准保持一致；而高概率洪水事件的选取，则反映了近数十年来观测到的实际洪水事件特征。