European Ground Motion Service: Calibrated 2015-2021 (vector), Europe, yearly, Feb. 2023

The European Ground Motion Service (EGMS) is a component of the Copernicus Land Monitoring Service. EGMS provides consistent, regular, standardised, harmonised and reliable information regarding natural and anthropogenic ground motion phenomena over the Copernicus Participating States and across national borders, with millimetre accuracy. This set of metadata describes the third product level of EGMS: Ortho. The EGMS Ortho product exploits the information provided by ascending and descending orbits of the Calibrated product (https://sdi.eea.europa.eu/catalogue/srv/eng/catalog.search#/metadata/bef2507a-13cf-44c0-a809-0a1566f27631) to derive two further layers; one of purely vertical displacements (the one described by this metadata), the other of purely east-west displacements. Both layers are resampled to a 100 m grid. The Ortho product eases the interpretation process of non-experts since the viewing geometry has not to be considered anymore. EGMS Ortho is visualised as a vector map of measurement points colour-coded by average velocity (vertical or east-west components) and distributed to users in comma-separated values format. Each point is associated with a time series of displacement, i.e. a plot with values of displacement per acquisition of the satellite.

欧洲地面运动服务（European Ground Motion Service，EGMS）是哥白尼陆地监测服务（Copernicus Land Monitoring Service）的组成单元。EGMS可为哥白尼参与国及跨国境范围内的自然与人为地面运动现象提供一致、定期、标准化、统一且可靠的信息，精度可达毫米级。本次元数据所描述的为EGMS第三级产品：Ortho产品。EGMS Ortho产品借助校准产品（Calibrated product）的升轨与降轨轨道数据（https://sdi.eea.europa.eu/catalogue/srv/eng/catalog.search#/metadata/bef2507a-13cf-44c0-a809-0a1566f27631），生成两个额外图层：其一为纯垂直位移图层（即本次元数据所描述的对象），其二为纯东西向位移图层。两个图层均被重采样至100米分辨率的网格。Ortho产品无需再考虑观测几何条件，因此简化了非专业人员的解译流程。EGMS Ortho产品以按平均速度（垂直或东西向分量）着色的测量点矢量地图形式进行可视化，并以逗号分隔值（comma-separated values，CSV）格式向用户分发。每个测量点均关联有位移时间序列，即卫星每次过境采集时对应的位移值绘图。