Map visualisation service (WMS) of the dataset: Strategic Type C Noise Map — Night — Department of the North

The noise levels emitted by a given infrastructure during an average day are evaluated using numerical models producing isophone curves translated into noise zones, according to the index recommended for all modes of transport at European level, namely the Lden index and the Ln index. Strategic noise maps aggregate or translate these noise zones according to the type of strategic noise map, namely noise exposure maps, noise-affected areas, limit-value exceedance maps, and known or predictable noise level evolution maps.本数据集依据欧洲层面针对所有交通方式推荐的噪声评价指标——即Lden指数与Ln指数，采用数值模型生成等声级线（isophone curves）并将其转化为噪声分区，以此评估特定基础设施在平均单日的噪声排放水平。 战略噪声地图可根据自身所属类型，对上述噪声分区进行聚合或转化，其具体类型包括噪声暴露地图、噪声受影响区域地图、噪声限值超标地图以及已知或可预测的噪声水平演化地图。