COSMOS-Europe: a European network of cosmic-ray neutron soil moisture sensors

Abstract

Abstract. Climate change increases the occurrence and severity of droughts due to increasing temperatures, altered circulation patterns, and reduced snow occurrence. While Europe has suffered from drought events in the last decade unlike ever seen since the beginning of weather recordings, harmonized long-term datasets across the continent are needed to monitor change and support predictions. Here we present soil moisture data from 66 cosmic-ray neutron sensors (CRNSs) in Europe (COSMOS-Europe for short) covering recent drought events. The CRNS sites are distributed across Europe and cover all major land use types and climate zones in Europe. The raw neutron count data from the CRNS stations were provided by 24 research institutions and processed using state-of-the-art methods. The harmonized processing included correction of the raw neutron counts and a harmonized methodology for the conversion into soil moisture based on available in situ information. In addition, the uncertainty estimate is provided with the dataset, information that is particularly useful for remote sensing and modeling applications. This paper presents the current spatiotemporal coverage of CRNS stations in Europe and describes the protocols for data processing from raw measurements to consistent soil moisture products. The data of the presented COSMOS-Europe network open up a manifold of potential applications for environmental research, such as remote sensing data validation, trend analysis, or model assimilation. The dataset could be of particular importance for the analysis of extreme climatic events at the continental scale. Due its timely relevance in the scope of climate change in the recent years, we demonstrate this potential application with a brief analysis on the spatiotemporal soil moisture variability. The dataset, entitled “Dataset of COSMOS-Europe: A European network of Cosmic-Ray Neutron Soil Moisture Sensors”, is shared via Forschungszentrum Jülich: https://doi.org/10.34731/x9s3-kr48 (Bogena and Ney, 2021).

Exploring the combined use of SMAP and Sentinel-1 data for downscaling soil moisture beyond the 1 km scale

“…This could be achieved by expanding the study area and including more CRNS stations; e.g. there exists a network of about 50 CRNS stations across Europe (Bogena et al, 2022). The use of such a network for calibration of the downscaling parameters β and might be successful and hence improve the algorithm substantially.…”

“…The capacitance probes ground observations (Bircher et al, 2012a;Jensen and Refsgaard, 2018) are part of the International Soil Moisture Network (Dorigo et al, 2011(Dorigo et al, , 2013 and can be retrieved after registration from their website (https://ismn.earth/en/networks/?id=HOBE; ISMN, 2022). The CRNS data are part of the COSMOS-Europe network, which has been recently presented in an ESSD data paper (https://doi.org/10.5194/essd-14-1125-2022; Bogena et al, 2022) and are also stored on a PANGEA repository Andreasen (2019) (https://doi.org/10.1594/PANGAEA.909271).…”

Multi-objective calibration of the Community Land Model Version 5.0 using in-situ observations of water and energy fluxes and variables

“…To evaluate the performance of the CLM5 model we used measurements of LE, H, q and SWC in the top soil layer (0-20 cm). Four percolation lysimeters measured recharge q (Schelde et al, 2011) and measurements of SWC in the top soil was obtained from a cosmic ray neutron sensor (CRNS) 20 (Andreasen et al, 2020;Bogena et al, 2022). Two heat flux plates measured ground heat flux (G) at 0.05 meter below ground level (mbgl).…”

An Alternative Incoming Correction for Cosmic‐Ray Neutron Sensing Observations Using Local Muon Measurement

“…The CRNS method is now used by several research groups at increasing number of sites around the world (Andreasen et al., 2017) and a national CRNS soil moisture networks under the acronym of COSMOS have been established first in the United States and then in other nations: the United Kingdom, Australia, India (Evans et al., 2016; Hawdon et al., 2014; Upadhyaya et al., 2021; Zreda et al., 2012) and recently also in Europe (Bogena & Hey, 2022).…”