空气质量 - 气象 - 地面观测站的选址分类

[中文适用范围]： 本国际标准规定了各种传感器的暴露规则，但如果这些条件不满足，该怎么办？有些站点不遵守建议的暴露规则。因此，我们建立了一个分类系统，以帮助确定给定站点在小范围内（受周围环境影响）的代表性。因此，可以将1类站点视为参考站点。5类站点是指附近的障碍物为气象测量创造了不合适的环境，而该测量旨在代表广阔区域（至少数十平方公里）。站点类别越小，测量对广阔区域的代表性就越高。理想情况下，所有站点都应属于1类，但现实世界并非完美，因此需要做出一些妥协。即使站点类别编号较少（数量较大），对于需要在该特定站点（包括其局部障碍物）进行测量的特定应用来说，仍然很有价值。分类过程有助于网络参与者和管理者更好地考虑暴露规则，从而通常可以改进站点选址。至少，站点环境是已知的，并记录在元数据中。显然，完整地记录场地是可能的，而且建议这样做，但风险在于，完整记录的场地可能会增加元数据的复杂性，这往往会限制其操作用途。这就是为什么定义此选址分类来浓缩信息并促进这些元数据信息的操作使用。整个场地没有单一的分类编号。在场地测量的每个参数都有自己的类别，有时与其他参数不同。如果需要对场地进行全球分类，则可以使用参数类别的最大值。由于环境情况会随着一段时间而发生变化，应定期审查每个场地的评级。建议每年进行一次系统的目视检查：如果环境的某些方面发生了变化，则需要进行新的分类过程。至少每五年应对场地类别进行一次全面更新。 [外文原描述]： ISO 19289:2015 indicates exposure rules for various sensors, but what should be done when these conditions are not fulfilled? There are sites that do not respect the recommended exposure rules. Consequently, a classification has been established to help determine the given site's representativeness on a small scale (impact of the surrounding environment). The classification process helps the actors and managers of a network to better take into consideration the exposure rules and thus it often improves the siting. At least, the siting environment is known and documented in the metadata. It is obviously possible and recommended to fully document the site but the risk is that a fully documented site might increase the complexity of the metadata, which would often restrict their operational use. That is why this siting classification is defined to condense the information and facilitate the operational use of this metadata information. A site as a whole has no single classification number. Each parameter being measured at a site has its own class and is sometimes different from the others. If a global classification of a site is required, the maximum value of the parameters' classes can be used. In ISO 19289:2015, the classification is (occasionally) completed with an estimated uncertainty due to siting, which has to be added in the uncertainty budget of the measurement. This estimation is coming from bibliographic studies and/or some comparative tests. The primary objective of this classification is to document the presence of obstacles close to the measurement site.