The contribution of Citizens’ Observatories to validation of satellite‐retrieved soil moisture products

The GROW Observatory (GROW) will create a sustainable citizen platform and community to generate, share and utilise information on land, soil and water resources at a resolution hitherto not previously considered. The European Space Agency’s Sentinel‐1 is the first mission capable of providing high‐resolution soil moisture information, but a proper validation of Sentinel data remains a challenge given the scarcity of available in situ reference measurements. Establishment of a dense network of in situ measurement can bridge the gap in spatial resolution between in situ and satellite‐based soil moisture measurements enabling validation and calibration of ground and remotely measured soil moisture observations. The potential exists to answer scientific questions including the validity of satellite data, the impact of climate change on land management thus supporting the needs of growers and integrating citizen and scientific research to be more directly applicable and relevant.