Surface Water Flood Maps (FRM_FH_SURFACE_WATER_VELOCITY_H)

The following probabilities are available for surface water flooding: - High - 10 year return period - Medium - 200 year return period - Low - 200 year return period plus climate change using the UKCP09 high emissions scenario for the 2080s.The surface water hazard maps show (where available): - Flood extent - Flood depth - Flood velocities where appropriate. 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 bandsThe climate change scenario has been defined by United Kingdom Climate Projection 2009 (UKCP09) predictions for 2080 high emissions 95%ile predictions. Medium 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.本次数据集提供以下等级的地表积水洪涝（surface water flooding）概率情景： - 高概率情景：重现期为10年 - 中概率情景：重现期为200年 - 低概率情景：叠加2080年代英国气候预测2009（UKCP09）高排放情景下气候变化影响的200年一遇洪涝事件 地表积水洪涝风险地图（若有可用数据）将展示以下内容： - 洪涝淹没范围 - 洪涝水深 - 适宜场景下的洪涝流速。流速仅在适宜场景下展示；展示与否需结合输入数据可信度、建模方法与影响评估进行判定，当前流速分为四个等级进行呈现。 本数据集采用的气候变化情景，基于英国2009年气候预测（UKCP09）中2080年高排放情景下95%分位数的预测结果设定。 中、低概率洪涝情景的选取参照了苏格兰规划政策中的重现期标准，而高概率情景则基于近数十年来实际观测到的洪涝事件特征设定。