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.本数据集包含的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》所规定的洪水危险地图发布义务而制作。上述地图展示了海洋、河流及地表水引发洪水的风险区域。 针对河流洪水，设有以下概率分级： - 高概率：对应10年重现期洪水 - 中概率：对应200年重现期洪水 - 低概率：对应1000年重现期洪水，以及结合2080年代英国2009年气候预估（UKCP09）高排放情景的气候变化影响的200年重现期洪水 河流危险地图（如可获取）包含以下内容： - 洪水淹没范围 - 洪水水深 - 适宜场景下的洪水流速 本次采用的气候变化情景基于英国2009年气候预估（UKCP09）中2080年高排放情景下的95%分位数预测结果。 流速信息仅在适宜场景下予以呈现，其判定依据为输入数据的可信度、建模方法及影响评估结果，目前分为四个等级之一。 中、低概率洪水事件的选取标准与苏格兰规划政策中使用的重现期规范保持一致，而高概率洪水事件的选取则贴合近数十年间观测到的实际洪水灾情。