Publication Details

Category Text Publication
Reference Category Journals
DOI 10.5194/hess-27-723-2023
Licence creative commons licence
Title (Primary) Signal contribution of distant areas to cosmic-ray neutron sensors – implications for footprint and sensitivity
Author Schrön, M.; Köhli, M.; Zacharias, S. ORCID logo
Source Titel Hydrology and Earth System Sciences
Year 2023
Department MET
Volume 27
Issue 3
Page From 723
Page To 738
Language englisch
Topic T5 Future Landscapes
Data and Software links
Abstract This paper presents a new theoretical approach to estimate the contribution of distant areas to the measurement signal of cosmic-ray neutron detectors for snow and soil moisture monitoring. The algorithm is based on the local neutron production and the transport mechanism, given by the neutron–moisture relationship and the radial intensity function, respectively. The purely analytical approach has been validated with physics-based neutron transport simulations for heterogeneous soil moisture patterns, exemplary landscape features, and remote fields at a distance. We found that the method provides good approximations of simulated signal contributions in patchy soils with typical deviations of less than 1 %. Moreover, implications of this concept have been investigated for the neutron–moisture relationship, where the signal contribution of an area has the potential to explain deviating shapes of this curve that are often reported in the literature. Finally, the method has been used to develop a new practical footprint definition to express whether or not a distant area's soil moisture change is actually detectable in terms of measurement precision. The presented concepts answer long-lasting questions about the influence of distant landscape structures in the integral footprint of the sensor without the need for computationally expensive simulations. The new insights are highly relevant to support signal interpretation, data harmonization, and sensor calibration and will be particularly useful for sensors positioned in complex terrain or on agriculturally managed sites.
Persistent UFZ Identifier
Schrön, M., Köhli, M., Zacharias, S. (2023):
Signal contribution of distant areas to cosmic-ray neutron sensors – implications for footprint and sensitivity
Hydrol. Earth Syst. Sci. 27 (3), 723 - 738 10.5194/hess-27-723-2023