FOR 2694:  Large-Scale and High-Resolution Mapping of Soil Moisture on Field and Catchment Scales - Boosted by Cosmic-Ray Neutrons

• Subject Area: Geosciences
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 357874777

The exchange of water between atmosphere, biosphere, and hydrosphere is a result of complex interactions and feedback mechanisms, where soil moisture acts as the key state variable. Novel approaches are required to handle the related scale dependency of water fluxes. Corresponding state-of-the-art methods for observing soil moisture range from continuous point-scale measurements, via field-scale temporal snapshots to remote sensing products on the basin scale and beyond. Cosmic-ray neutron sensing (CRNS) constitutes a considerable advancement in this context by inferring soil moisture from changes in ambient neutron density above the ground, allowing for the integration across hundreds of meters. In this proposal we report on the activities and achievements of the Cosmic Sense research unit (RU) in its first phase, and give an outline of the objectives and the work program for the second phase. The overarching goal remains the development of a quantitative, adaptable, and transferable approach for observing root-zone soil moisture on the field scale while accounting for other dynamic water pools, such as biomass. New to phase II is the addition of snow water pools and the focus on the regional scale by soil moisture mapping with sensor clusters, mobile detectors, remote sensing, and modeling. Cosmic Sense continues to constitute a driving force in the field of soil moisture measurements via CRNS and will strengthen an engaged and innovative community. Our team will advance the understanding of field-scale and regional water storage and fluxes in the soil-vegetation-atmosphere continuum by bundling the expertise of distinguished partners in complementary research modules and joint activities. Working together towards joint research objectives requires intensive interaction in the team as well as overarching coordination and support. The coordination project “Z” acts as a central nexus for the objectives, resources, and outreach activities that are related to the RU as a whole. The key personal resources required are a position for the coordination of meetings, workshops, and general RU matters, and a field technician to support the joint field- and cross-cutting activities. Furthermore, Z strives to support young researchers – particularly those with children – in their work and career, and to enhance gender equality. Z will also promote the outcomes of the RU in a closing workshop, inviting external keynote speakers and supporting attendance via discounts and scholarships. The current and designated Mercator Fellow, Prof. Marek Zreda, will interact with all research modules, he will actively participate in the cross-cutting activities and promote the achievements of Cosmic Sense to the scientific community worldwide. Accordingly, all of the tasks planned in Z will support and interact with the involved research modules of the RU, thus helping to promote the collaboration within the RU and of the dissemination of its outcomes beyond it.

• DFG Programme: Research Units
• International Connection: Austria, Italy, Netherlands

Projects

• Coordination Funds (Applicant Oswald, Sascha E. )
• Cosmic Sense – Hydrological Modeling: Coupled distributed modeling of soil moisture, snow and atmosphere interaction – tuned by cosmic-ray neutron sensing (Applicants Hendricks-Franssen, Harrie-Jan ;  Kunstmann, Harald )
• CRNS and root zone soil moisture dynamics in agricultural land (Applicants Attinger, Sabine ;  Oswald, Sascha E. )
• Detector Development; Detectors tailored for different aspects of CRNS applications (Applicant Schmidt, Ulrich )
• From local CRNS network observations to meso-scale soil moisture distributions (Applicants Attinger, Sabine ;  Huisman, Johan ;  Oswald, Sascha E. )
• Hydrogeodesy - Going deep: combining CRNS with other non-invasive soil moisture measurements with varying integration depths (Applicants Blume, Theresa ;  Güntner, Andreas )
• Improved soil moisture and biomass quantification through combination of ground-based neutron and LiDAR sensing and modeling (Applicants Bogena, Heye ;  Huisman, Johan )
• Integrating Remote Sensing Information in the Cosmic Ray Neutron Sensing Signal for Soil Moisture Modelling and Sampling (Applicants Förster, Michael ;  Kleinschmit, Birgit )
• Neutron Simulation; Developing a theoretical framework for CRNS (Applicant Schmidt, Ulrich )
• Roving & Airborne -- Upscaling soil moisture products with ground- and airborne neutron sensing (Applicants Schrön, Martin ;  Zacharias, Steffen )
• Snow Dynamics (Applicant Schattan, Ph.D., Paul )

• Spokesperson: Professor Dr. Sascha E. Oswald