GI6.4
Cosmic rays across scales and disciplines: the new frontier in environmental research

GI6.4

EDI
Cosmic rays across scales and disciplines: the new frontier in environmental research
Co-organized by AS4/PS2/ST1
Convener: Martin SchrönECSECS | Co-conveners: Marek Zreda, Konstantin HerbstECSECS, W. Rühm, Jannis WeimarECSECS
Presentations
| Fri, 27 May, 15:10–16:30 (CEST)
 
Room 0.51

Presentations: Fri, 27 May | Room 0.51

Chairpersons: Martin Schrön, Jannis Weimar
15:10–15:17
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EGU22-9438
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On-site presentation
Monika Korte, Jiawei Gao, and Sanja Panovska

The geomagnetic field prevents energetic particles, such as galactic cosmic rays, from directly interacting with the Earth's atmosphere. The geomagnetic field is not static but constantly changing, and over the last 100,000 years several geomagnetic excursions occurred. During geomagnetic field excursions, the field strength is significantly decreased and the field morphology is controlled by non-dipole components, and more cosmic ray particles can access the Earth's atmosphere. Paleomagnetic field models provide a global view of the long-term geomagnetic field evolution, however, with individual spatial and temporal resolution. Here, we reconstruct the geomagnetic shielding effect over the last 100,000 years by calculating the geomagnetic field cutoff rigidity using four global paleomagnetic field models, i.e., GGF100k, GGFSS70, LSMOD.2, and CALS10k.2. We find that the non-dipole components of the geomagnetic field are not negligible for estimating the long-term geomagnetic shielding effect, in particular during excursions. Our results indicate that cosmic ray flux, impact area, and cosmic ray radiation intensity increase strongly during the excursions. Our results provide the possibility to accurately estimate the cosmogenic isotope production rate and cosmic radiation dose rate covering the last 100,000 years.

How to cite: Korte, M., Gao, J., and Panovska, S.: Geomagnetic field shielding over the past 100 000 years, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9438, https://doi.org/10.5194/egusphere-egu22-9438, 2022.

15:17–15:24
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EGU22-5539
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Virtual presentation
Bernd Heber, Sasa Banjac, Sönke Burmeister, Martin Zoska, Hanna Giese, Konstantin Herbst, Lisa Romaneehsen, Carolin Schwerdt, Dutoit Stauss, Carsten Wallmann, Adrian Vogt, and Michael Walter

Galactic cosmic rays (GCRs) consist of energetic electrons and nuclei which are a direct sample of material from far beyond the solar system. Measurements by various particle detectors have shown that the intensity varies on different timescales, caused by the Sun’s activity and geomagnetic variation. Interplanetary disturbances cause space weather effects which warrant a more detailed study. Many studies on GCR intensity decreases is based on the analysis of ground-based neutron monitors and muon telescopes. Their measurements depend on the geomagnetic position, and the processes in the Earth's atmosphere. In order to get a better understanding of the geomagnetic filter over the solar cycle, the Christian-Albrechts-Universität zu Kiel, DESY Zeuthen, and the North-West University in Potchefstroom, South Africa agreed on a regular monitoring of the GCR intensity as a function of latitude, by installing a portable device aboard the German research vessel Polarstern in 2012. The vessel is ideally suited for this research campaign because it covers extensive geomagnetic latitudes (i.e. goes from the Arctic to the Antarctic) at least once per year. Here we present the measurements for different latitude surveys including the periods of solar maximum in 2014 and solar minimum in 2019. 

The Kiel team received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 870405. The team would like to thank the crew of the Polarstern and the AWI for supporting our research campaign.

How to cite: Heber, B., Banjac, S., Burmeister, S., Zoska, M., Giese, H., Herbst, K., Romaneehsen, L., Schwerdt, C., Stauss, D., Wallmann, C., Vogt, A., and Walter, M.: Measurements of cosmic rays by a mini neutron monitor aboard the German research vessel Polarstern., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5539, https://doi.org/10.5194/egusphere-egu22-5539, 2022.

15:24–15:34
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EGU22-11230
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solicited
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On-site presentation
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Stefan Terzer-Wassmuth, Luis J. Araguas-Araguas, Lorenzo Copia, and Jodie A. Miller

The generation of cosmogenic tritium (3H) through spallation of 14N in the upper atmosphere and a its decay (half-life of 12.32 y) are the two main processes resulting in the global steady-state inventory of tritium in the hydrosphere of approximately 2.95 kg. Various mechanisms of scavenging of stratospheric 3H into the troposphere, such as stratosphere-troposphere transports (STTs) during the so-called “spring leak”, or the tropospheric distribution by means of the Brewer-Dobson circulation, have been described to explain the observed spatial and seasonal distribution of present-day tritium levels in global precipitation. Following thermonuclear weapons testing prior to the Preliminary Test Ban Treaty in 1963, the natural 3H input signal was overlaid by the so-called “bomb peak”. This characteristic tritium pulse has been used for decades in nuclear and hydrological sciences, with 3H values in Vienna, the reference northern hemisphere station of the IAEA-WMO Global Network of Isotopes in Precipitation (GNIP), peaking in 1963 at approximately 400 Bq L-1. Since the year 2000, this 3H pulse has dissipated in the northern hemisphere, and 3H levels at the Vienna monitoring site have reached their natural background value of ca. 1.2 Bq L-1.

The present-day steady state of natural 3H levels in precipitation allow to research their inter-annual variability as driven by cosmogenic input, with particular emphasis on neutron flux intensity governed by the 11-year sunspot cycles. With almost two full solar cycle’s worth of observed 3H data in Vienna’s precipitation and other GNIP stations in the northern hemisphere, we discuss the impact of the neutron flux (as exemplified by the Oulu Neutron Monitor) in modulating the inter-annual variability. Our findings showed that while 52% of the interannual variability was explained by changes in the cosmogenic flux, an additional 31% of the variability resulted from the seasonal distribution of the amount of precipitation, a finding prominent in the previous solar cycle valley, particularly in the year 2015, that coincided with abnormally high winter precipitation.

While the regular oscillations of the neutron flux seem to constitute the main driver of the observed interannual changes of 3H contents in precipitation, atmospheric circulation processes were of varying importance in 15 GNIP stations. In spite of the relative data paucity (i.e. absence of sufficiently long records at even spatial distribution), we hypothesize that changes in precipitation seasonality, due to climate change impacts on global or regional atmospheric circulation patterns, may drive fluctuations in the natural steady-stage 3H levels in precipitation used to investigate atmospheric and hydrological processes. Hence, we stress the importance of spatially and temporally adequate observational baselines on a global level.

How to cite: Terzer-Wassmuth, S., Araguas-Araguas, L. J., Copia, L., and Miller, J. A.: Space or climate? Disentangling cosmogenic and climatic drivers of present-day tritium (3H) in global precipitation, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11230, https://doi.org/10.5194/egusphere-egu22-11230, 2022.

15:34–15:41
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EGU22-12618
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ECS
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On-site presentation
Kseniia Golubenko

Cosmogenic isotopes are mostly produced in the stratosphere and troposphere, and the corresponding fractions depend on solar activity and tropopause altitude. Solar-cycle variability of cosmogenic isotope production is the strongest at high latitudes due to the lack of geomagnetic shielding. However, the exact zonal distribution of the production in troposphere and stratosphere regions, that is needed for the precise modelling of their transport and deposition, is not clear. In this work, we provide numerical estimates of cosmogenic isotopes production in the atmosphere for different conditions. Using the SOCOL-AER2-BE Chemical Climatic model (CCM), we present simulations of the production of cosmogenic isotopes ($^{14}$C, $^{36}$Cl, $^{10}$Be, and $^{7}$Be) and provide zonal distributions (tropical, subtropical, and polar regions) in the stratosphere and troposphere. The model is driven by four solar activity scenarios: 1) solar minimum year with solar modulation function - phi = 400 MeV and 2) solar maxima year with phi = 1100MeV. In these cases, the production is modulated by Galactic Cosmic Rays (GCR). Two other scenarios are 3) ground-level enhancement (GLE) event number 5 with hard spectrum on February 23, 1956 and 4) GLE event number 24 with soft spectrum on August 04, 1972. The production rates were calculated using a combination of the SOCOL and CRAC models.

How to cite: Golubenko, K.: Zonal distribution of cosmogenic isotopes in stratosphere and troposphere via CCM SOCOL, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12618, https://doi.org/10.5194/egusphere-egu22-12618, 2022.

15:41–15:48
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EGU22-4659
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On-site presentation
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Kateřina Podolská, Michal Kozubek, Miroslav Hýža, and Tereza Šindelářová

Cosmogenic radionuclides concentrations are predominantly determined by the solar activity and space weather around the Earth, forming an important source of cosmic-origin background radiation in the terrestrial environment. The highest values of such radiation are observed during the solar minima because the penetrability of the Earth’s magnetosphere is greatest at that time. Beryllium 7Be binds to aerosols and is transported within a few years to the Earth’s surface. Its concentrations are higher during the spring and summer months when the stratospheric 7Be penetrates the troposphere as a result of the exchange of air masses between the troposphere and stratosphere. We compare periods of strong solar and geomagnetic storms with periods of very low solar activity in the longitudinal view during the years 1986 – 2020.

For a better understanding of the process dynamics, in our work we investigate the coupling of concentrations of the cosmogenic radionuclide 7Be (time series of activity concentration of 7Be in aerosols) to space weather parameters around the Earth (Kp planetary index, disturbance storm time Dst, proton density, proton flux), proxy parameters of the solar activity (intensity of solar radio flux, relative sunspot number), stratospheric dynamics parameters (temperature, zonal component of wind, O3), and aggregates of strong atmospheric frontal transition. The beryllium radionuclide 7Be concentration was evaluated by the corresponding activity in aerosols on a weekly basis at the National Radiation Protection Institute Monitoring Section in Prague.

We also perform the case study of cosmogenic radionuclide 7Be concentrations during the period of strong solar and geomagnetic storm in November 2021 with the ERA5 reanalysis data, and Aeolus satellite lidar wind measurements.

How to cite: Podolská, K., Kozubek, M., Hýža, M., and Šindelářová, T.: The effect of space weather, proxy parameters of solar activity, and stratospheric phenomena on the concentration of cosmogenic radionuclide 7Be (in the Czech Republic), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4659, https://doi.org/10.5194/egusphere-egu22-4659, 2022.

15:48–15:55
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EGU22-8872
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ECS
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Virtual presentation
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Faezeh Karimian Sarakhs, Fabio Madonna, Marco Rosoldi, and Salvatore De Pasquale

Abstract

High energy Cosmic Ray (CR) particles are capable of ionizing the Earth’s atmosphere, which leads to changes in the atmospheric physical and chemical properties. One of the most important effects of interactions between the CR particles and atmospheric molecules is the formation of aerosol and its subsequent condensation nuclei processes. These interactions are known with considerable uncertainty yet and may translate into even bigger uncertainties in future climate predictions. Laser Detection and Ranging (LIDAR) is currently the best suited technology to retrieve aerosol optical and microphysical properties is also used for the atmosphere correction of high energy cosmic ray observatory data. LIDAR measurements are available from single stations or from networks at continental scale like the European Aerosol Research LIdar NETwork (EARLINET). Sun photometer data are the most suitable complement to LIDAR measurements for the study of aerosol properties due to the extensive coverage of their measurements available through the AErosol RObotic NETwork (AERONET) network. The purpose of this study is to find the correlation between the aerosol properties and the CR data. The aerosol properties retrieved from two databases for the period of 2016-2020: I) the multi-wavelength LIDAR system Potenza EArlinet Raman Lidar (PEARL) which operates at the CNR-IMAA (Tito Scalo (Italy) and contributes to the EAELINET); and II) the AERONET sun photometer data from the stations located at Southern Italy i.e. Potenza (40.60° N, 15.72° E, 820m), Naples (40.83° N, 14.30° E, 50 m) and Lecce (40.33° N, 18.11° E, 30m). whereas, the CR data made available in Italy from the Extreme Energy Events project (http://eee.centrofermi.it/monitor). Air mass back-trajectories were used to confirm the observed aerosol types and support the correlation study. Our study showed promising results in understanding the relationship between cosmic ray and aerosol properties.

Keywords: Cosmic Ray, Aerosol, Lidar, Sun Photometer, Back-trajectory

How to cite: Karimian Sarakhs, F., Madonna, F., Rosoldi, M., and De Pasquale, S.: Relationship between the time series of cosmic ray data and aerosol optical properties: (Case study: southern Italy, 2016-2020), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8872, https://doi.org/10.5194/egusphere-egu22-8872, 2022.

15:55–16:02
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EGU22-6430
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ECS
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Virtual presentation
Hanna Giese, Bernd Heber, Konstantin Herbst, and Martin Schrön

Neutrons on Earth interact with the soil and are substantially moderated by hydrogen atoms. Since the reflected neutron flux is a function of the soil water content, cosmic-ray neutron measurements above the ground can be used to estimate the average field soil moisture. Thus, if the local incoming neutron flux and the abundance of nearby hydrogen pools are known, the reflected neutron flux could be modeled and compared to observed detector count rates. However, the incoming neutrons are secondaries produced by interacting energetic Galactic Cosmic Rays (GCRs) in the atmosphere. The total neutron flux on the ground depends on the solar modulation-dependent GCR flux, the geomagnetic position, and the altitude within the atmosphere. So far, measurements of either the Jungfraujoch neutron monitor (NM) or a NM of similar cutoff rigidity have been used and altered to estimate the neutron flux at the position of each neutron detector. In this contribution we present a new method based on the Dorman function to directly compute the local neutron flux using remote neutron monitor data.

We received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 870405

How to cite: Giese, H., Heber, B., Herbst, K., and Schrön, M.: Utilizing Cosmic Ray data as input for neutron-based soil moisture measurement, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6430, https://doi.org/10.5194/egusphere-egu22-6430, 2022.

16:02–16:09
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EGU22-6238
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ECS
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Highlight
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On-site presentation
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Cosimo Brogi, Heye Reemt Bogena, Markus Köhli, Harrie-Jan Hendricks Franssen, Olga Dombrowski, Vassilios Pisinaras, Anna Chatzi, Kostantinos Babakos, Jannis Jakobi, Patrizia Ney, and Andreas Panagopoulos

Water availability is a key challenge in agriculture, especially given the expected increase of droughts related to climate change. Soil moisture (SM) sensors can be used to collect information on water availability in a reliable and accurate way. However, due to their very small measuring volume, the installation of multiple sensors is required. In addition, in-situ sensors may need to be removed during field management and connecting cables are often damaged by rodents and other wilderness animals. Hence, the demand for SM sensors that do not have such limitations will increase in the upcoming years. A promising non-invasive technique to monitor SM is cosmic-ray neutron sensing (CRNS), which is based on the negative correlation between fast neutrons originating from cosmic radiation and SM content. With its large measuring footprint of ~130-210m, CRNS can efficiently cover the field-scale. However, heterogeneous agricultural management (e.g., irrigation) can lead to abrupt SM differences, which pose a challenge for the analysis of CRNS data. Here, we investigate the effects of small-scale soil moisture patterns on the CRNS signal by using both modelling approaches and field studies. The neutron transport model URANOS was used to simulate the neutron signal of a CRNS station located in irrigated plots of different sizes (from 1 to 8 ha) with different soil moisture (from 5 and 50 Vol.%) inside and outside such a plot. A total of 400 different scenarios were simulated and the response functions of multiple detector types were further considered. In addition, two CRNS with Gadolinium shielding were installed in two irrigated apple orchards of ~1.2 ha located in the Pinios Hydrologic Observatory (Greece) in the context of the H2020 ATLAS project. Reference soil moisture was determined using 25 SoilNet stations, each with 6 SM sensors installed in pairs at 5, 20 and 50 cm depth and water potential sensors at 20 cm depth. The orchards were also equipped with two Atmos41 climate stations and eight water meters for irrigation monitoring. The CRNS were calibrated using either soil samples or the SM measured by the SoilNet network. In the URANOS simulations, the percentage of neutrons detected by the CRNS that are representative of an irrigated plot varied between 45 and 90% and was strongly influenced by both the dimension and SM of the irrigated plot. As expected, the CRNS footprint decreased considerably with increasing SM but did not appear to be influenced by the plot dimension. SM variation within the irrigated plot strongly affected the neutron energy at detection, which was not the case for SM variations outside the plot. The instrumented fields corroborated the URANOS findings and the performance of the local CRNS was dependent on a) the timing and intensity of irrigation and precipitation, b) the CRNS calibration strategy, and c) the management of the surrounding fields. These results provide novel and meaningful information on the impact of horizontal SM patterns on CRNS measurements, which will help to make CRNS more useful in irrigated agriculture.

How to cite: Brogi, C., Bogena, H. R., Köhli, M., Hendricks Franssen, H.-J., Dombrowski, O., Pisinaras, V., Chatzi, A., Babakos, K., Jakobi, J., Ney, P., and Panagopoulos, A.: Challenges and solutions for cosmic-ray neutron sensing in heterogeneous soil moisture situations related to irrigation practices, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6238, https://doi.org/10.5194/egusphere-egu22-6238, 2022.

16:09–16:16
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EGU22-12812
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ECS
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On-site presentation
Martin Schrön, Markus Köhli, and Steffen Zacharias

Cosmic-Ray Neutron Sensing (CRNS) is an established measurement technique for water content in soils and snow. The high integration depth and the large measurement footprint is an important advantage compared to conventional point-scale sensors. However, the radial-symmetrical footprint definition based on the 86% quantile of detected neutrons is often not helpful to explain the influence of certain areas in complex fields. Many natural sites are highly heterogeneous and thus knowledge of the contribution of distant areas to the measurement signal would be very useful, e.g. to support calibration sampling, sensor location design, data interpretation, and uncertainty assessment. Here, CRNS calibration and validation remains a challenge, since the influence of the different fields and structures to the signal is usually not known.

In this presentation, we proposes a generalized analytical procedure to estimate the contribution of patches or fields in the footprint of a cosmic-ray neutron detector to its signal using the radial intensity functions. The proposed method could greatly support calibration sampling, sensor location design, and uncertainty assessment, e.g. in complex or vegetated terrain, without the need of computationally expensive neutron modeling. Furthermore, a new concept for a more practical definition of the sensor footprint is proposed, which represents the maximal distance to a field such that its soil moisture change is still sensible in terms of measurement precision. 

How to cite: Schrön, M., Köhli, M., and Zacharias, S.: Signal contribution of remote areas to cosmic-ray neutron sensors based on distance and sensitivity, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12812, https://doi.org/10.5194/egusphere-egu22-12812, 2022.

16:16–16:23
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EGU22-12334
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On-site presentation
Daniel Altdorff, Sascha Oswald, Steffen Zacharias, Carmen Zengerle, Hannes Mollenhauer, Peter Dietrich, Sabine Attinger, and Martin Schrön

Cosmic ray neutron sensing (CRNS) has become an established method for deriving the soil water content (SWC), based on the inverse relationship of neutron counting and the SWC of the surrounding area. The provided footprint, lateral up to 200m and vertical of several decimeter, qualifies CRNS to bridge the information gap between classical hydrogeophysical approaches and remote sensing. While stationary CRNS offers continuous long-term SWC measurements at high temporal resolution, the covered area remains fixed and predefined. Car-borne CRNS roving on the other hand, allows to expand the mapped area. However, the method requires active operation and is limited to snap shot information only. As an alternative, the operation of a permanent mobile CRNS platform on trains promises to combine the advantages from stationary and car-borne CRNS measurements, as recently suggested by Schrön et al. (2021), while also its technical implementation, data processing and interpretation raises new challenges and complexity.

In this study we introduce a fully automatic CRNS railway system, installed in a conventional locomotive of a freight train, as first and novel of its kind. Results of the first phase of operation will be presented. The measurements along an experimental rail track were supported by local SWC measurements, gravimetric and dielectric records (Mobile Wireless Ad-hoc Sensor Network), at three areas along the railway, and by a newly installed weather station. Additionally, car-borne CRNS data were recorded on two days close to the railway track.

Preliminary results of data collected between September and December 2021 showed very stable spatial pattern in relation to the segments crossed by the train, which have been confirmed by the car-borne dataset. Temporal variations within hours were also evident as direct or indirect response to local rain and snow events.  Based on the first results, we are confident, that rail-based CRNS offers the chance to play a prominent role in addressing soil hydrology at landscape scale in the future.

Schrön, M., Oswald, S. E., Zacharias, S., Kasner, M., Dietrich, P., & Attinger, S. (2021). Neutrons on rails: Transregional monitoring of soil moisture and snow water equivalent. Geophysical Research Letters, 48, e2021GL093924

 

How to cite: Altdorff, D., Oswald, S., Zacharias, S., Zengerle, C., Mollenhauer, H., Dietrich, P., Attinger, S., and Schrön, M.: Rail-based cosmic ray neutron sensing (CRNS): pushing the boundaries towards expanding footprints and temporal resolutions, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12334, https://doi.org/10.5194/egusphere-egu22-12334, 2022.

16:23–16:30
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EGU22-9264
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ECS
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On-site presentation
Patrick Stowell and the COSMIC-SWAMP and STFC Food Network+ Collaborations

Cosmic ray neutron sensing has been shown to be a powerful method for continuously monitoring soil moisture over large areas. This technique relies on the detection of albedo cosmic ray neutrons coming from from the soil to infer the local hydrogen content. Cosmic ray neutron sensing is well-suited for hydrological monitoring in the field sizes typically seen on smallholder farms. The ongoing development of new lower-cost neutron detector instrumentation and processing tools will help to further support the adoption of this novel technique within the agricultural industry.

In this presentation I will discuss recent efforts at Durham University (UK) to develop low-cost cosmic ray neutron detectors to support soil moisture monitoring in the agriculture sector. These systems rely on lithium and boron-based scintillator foils for thermal neutron detection. Recent pilot studies in collaboration with the COSMOS-UK network have shown that the detected neutron rate in these sensors correlates well with results obtained from traditional gaseous systems. Work is now underway to improve the robustness of these scintillator systems for use in agricultural and civil engineering applications. 

In addition, I will present a new international research network, COSMIC-SWAMP, which is looking at the integration of cosmic ray neutron sensors with managed irrigation sites in Brazil. By combining low-cost neutron probes with a smart water management platform (SWAMP), this research network is looking at using cosmic ray neutrons to perform data-driven irrigation control over large areas. The instrumentation being considered for COSMIC-SWAMP will be presented before discussing the future plans for the network.

How to cite: Stowell, P. and the COSMIC-SWAMP and STFC Food Network+ Collaborations: Smart Scintillating Neutron Detectors for Soil Moisture Monitoring, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9264, https://doi.org/10.5194/egusphere-egu22-9264, 2022.