EO Capability Benefits
Cloud masking, i.e. filtering out pixels where clouds block the spectral information from the actual object of analysis, such as land surfaces, is a critical pre-processing step for many Earth Observation applications. It allows users to study only images where the percentage of cloud cover falls below a user-defined threshold. Moreover, cloud monitoring is useful in itself for weather forecasting and tracking cloud systems, providing critical information for disaster management and early warning. Long-term cloud trends inform climate studies, while cloud cover data also improves solar energy forecasting and site selection for solar farms.
EO Capability Description
The Cloud Cover layer describes the spatial distribution of cloud occurrence derived from multi-temporal Sentinel-2 optical data acquisitions. It quantifies the relative proportion of acquisitions covered by clouds over all scenes over a multi-year analysis period. The calculation is based on imagery of both Sentinel-2A and -2B, providing a global coverage with a nominal revisit time of approximately five days at the equator and higher temporal sampling at mid and high latitudes. Daily acquisitions are limited to daylight conditions (around 10:30 a.m. local times). Since they are influenced by orbital geometry and latitude-dependent revisit frequency, the values might change alongside with acquisitions strips and overlaps. Spatial resolution is 10m.
The Cloud Cover (frequency) layer is particularly relevant for photovoltaic site selection. It is calculated as the ratio between the number of cloudy observations and the total number of valid observations per pixel. The resulting values range from 0 (no cloud occurrence) to 1 (clouds present in all valid observations).
Indicative Cost Range Details
As cloud detection and masking is an integral part of processing chains for multi- and hyperspectral imagery, it is usually not sold as a separate data product. EUMETSAT’s Satellite Application Facility on Climate Monitoring (CM SAF) offers various cloud products as daily or monthly composites.
Indicative Cost Range
Free
