Dynamic mosaic of Sentinel-2 data NW

The Dynamic Mosaic is composed of recent cloud-free Sentinel-2 orthoimages. The two identically constructed Sentinel-2 satellites of the European earth observation program Copernicus have been continuously providing images of the earth's surface since 2015 and 2017 respectively. The multispectral optical sensor has 13 spectral channels in the visible and infrared range. The spatial resolution varies from 10 m (channels B02, B03, B04, B08) to 20 m (channels B05, B06, B07, B08A, B11, B12) up to 60 m (channels B01, B09, B10). The Sentinel-2 data is originally offered in the processing levels Level-1C (Top-Of-Atmosphere) and Level-2A (Bottom-Of-Atmosphere) and in tile sizes of 100 x 100 km2 in UTM/WGS84 projection. Due to the high return rate of the satellites, up-to-date recordings are available across the whole of NRW every 2-3 days. Since the multispectral instrument is a passive system, the usability of the recordings depends on the weather. The available orthoimages show different degrees of cloud cover. To derive the dynamic mosaic, the current Sentinel-2 images are checked for cloud cover so that the cloud-free areas can be selected. Areas of older recordings are continuously replaced with current cloud-free images. The 4 spectral bands with a spatial resolution of 10 m (red, green, blue, near infrared) of the Level-2A data are taken into account. The data set is updated if there is a cloud-free area from a size of 100 connected 10 m x 10 m pixels, so that the current cloud-free images are always included in the mosaic. The dynamic mosaic is provided as a display service in the forms RGB (composite from the spectral bands B04-B03-B02) and CIR (composite from the spectral bands B08-B04-B03). In addition, the recording date of the respective Sentinel-2 scene is provided for each cloud-free area. The recording date is displayed via the attribute data query of the metadata layer.