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Better monitoring of soil carbon sequestration is needed to understand the best carbon farming practices in different soils and climate conditions. We, the Field Observatory Network (FiON), have therefore established a methodology for monitoring and forecasting agricultural carbon sequestration by combining offline and near-real-time field measurements, weather data, satellite imagery, and modeling. To disseminate our work, we built a website called the Field Observatory (fieldobservatory.org).

Weather balloons are released every day around the world to obtain the latest atmospheric data for weather forecasting. Expanding the range of sensors they carry can make additional quantities available, such as for atmospheric turbulence, cloud electricity, energetic particles from space and, in emergency situations, volcanic ash or radioactivity. An adaptable system has been developed to provide these and other measurements, without interfering with the core weather data.

Soil evaporation is one of the most important water vapor sources on the Earth with multiple and severe consequences; however, there is a relative lack of instruments to measure it. This study describes a simple apparatus making the soil evaporation measurement accessible. The soil evaporation complexity is overcome by measuring the evaporation dynamic under different measurement conditions. A relatively simple measurement correction is then performed depending on the wind speed.

The goal is to reduce the uncertainty in air quality assessment by imputing all missing pollutants in monitoring stations and identify where more measurements can be beneficial. The proposed approach is based on spatial or temporal similarity between stations. Our proposed approach enables us to impute and estimate plausible concentrations of multiple pollutants at stations across the UK, and the modelled concentrations from the selected models correlated well with the observed concentrations.

Cosmic-ray neutron sensing (CRNS) is a non-invasive tool for measuring hydrogen pools like soil moisture, snow, or vegetation. This study presents a directional shielding approach, aiming to measure in specific directions only. The results show that non-directional neutron transport blurs the signal of the targeted direction. For typical instruments, this does not allow acceptable precision at a daily time resolution. However, the mere statistical distinction of two rates is feasible.

Methods for reconstruction of winter long data gaps in snow depth time series are compared. The methods use snow depth data from neighboring stations or calculate snow depth from temperature and precipitation data. All methods except one are able to reproduce the average snow depth and maximum snow depth in a winter reasonably well. For reconstructing the number of snow days with snow depth ≥ 1 cm, results suggest using a snow model instead of relying on data from neighboring stations.

We have developed a towed magnetic gradiometer system for rapid acquisition of magnetic and magnetic gradient maps. This high-resolution system is flexible and has applications to utility detection, archaeology, unexploded ordnance, or any other applications where high-resolution maps of the magnetic field or gradient are required. Processing of the data has been simplified as much as possible to facilitate rapid results and interpretations.

The quality control and validation activities performed by the Swarm data quality team reveal the good-quality LPs. The analysis demonstrated that the current baseline plasma data products are improved with respect to previous baseline. The LPs have captured the ionospheric plasma variability over more than half of a solar cycle, revealing the data quality dependence on the solar activity. The quality of the LP data will further improve promotion of their application to a broad range of studies.

Based on the intercomparison of photoacoustic and cavity attenuation phase shift instruments, this paper has corrected and calibrated the data of recent field measurements. It showed good agreement and close correlation in the optical properties measured from different optical methods, and the scattering coefficient plays a crucial role as the bridge in constructing correlation between both instruments.

When radio waves from our galaxy enter the Earth's atmosphere, they are absorbed by electrons in the upper atmosphere. It was thought that by measuring the amount of absorption, it would allow the height of these electrons in the atmosphere to be determined. If so, this would have significance for future instrument design. However, this paper demonstrates that it is not possible to do this, but it does explain how multiple-frequency measurements can nevertheless be useful.

For the processing of geomatics data, artificial intelligence (AI) offers overwhelming opportunities. The integration of AI approaches in geomatics has developed into the concept of geospatial artificial intelligence (GeoAI), which is a new paradigm for geographic knowledge discovery and beyond. This contribution outlines AI-based techniques for analysing and interpreting complex geomatics data. How AI approaches have been exploited for the interpretation of geomatic data is explained.

The study was conducted along the Luangwa River in Zambia. It combines low-cost instruments such as UAVs and GPS kits to collect data for the purposes of water management. A novel technique which seamlessly merges the dry and wet bathymetry before application in a hydraulic model was applied. Successful implementation resulted in water authorities with small budgets being able to monitor flows safely and efficiently without significant compromise on accuracy.

The objective of this paper is to present a new architecture of a solution for object detecting and blurring. Our algorithm is tested on four data sets of panorama images. The percentage of accuracy, i.e., the successfully detected objects of interest, is higher than 97 % for each data set. The proposed algorithm has a wide application for images of different types, surveyed with various purposes, and also for the detection of different types of objects.

In this paper, we study the compensation method of the helicopter towed bird. We will affect the compensation results based on the geomagnetic gradient. Therefore, we build a compensation model based on the geomagnetic gradient, which is 6 % higher than the traditional model. When the helicopter towed bird system is used for magnetic target exploration, this method can be used to eliminate the interference generated by the helicopter towed bird system and further accurately detect the target.

We present an experiment intended to enable extremely low-noise magnetic field measurements. We manufactured fluxgate magnetometer cores using two metal alloys, two geometries, two foil thicknesses, and six different heat treatments and compared the resulting material properties, power consumption, and magnetic noise. Our results suggest that thinner foils, potentially using a new copper alloy, manufactured into continuous racetrack washers may provide excellent performance in fluxgate sensors.

We use technical methods of instrument development, calibration experiments, and numerical simulations to develop a new type of in situ stress sensor group using fiber Bragg grating (FBG) sensing technology, which can calculate the in situ stress state of surrounding rock mass by sensing the borehole wall strain. This sensor group lays an important theoretical and experimental foundation for the development and application of FBG hole wall strain gauge.

We propose a newly developed modular MObile LIdar SENsor System (MOLISENS) to enable new applications for small industrial light detection and ranging (lidar) sensors. MOLISENS supports both monitoring of dynamic processes and mobile mapping applications. The mobile mapping application of MOLISENS has been tested under various conditions, and results are shown from two surveys in the Lurgrotte cave system in Austria and a glacier cave in Longyearbreen on Svalbard.

In recent years, imaging of density inside volcanoes using cosmic-ray muons has been studied. In some previous studies, observations were conducted in 2 or 3 directions to obtain 3D resolution. For higher resolution, we tried to observe a volcano from 11 directions using special photographic films. The observation and analytical techniques developed in this study may be applied to other volcanoes and large objects. Reconstructing 3D images of the volcano is in progress using the obtained data.

Surface energy balance (SEB) closure check and important environmental variable monitoring require soil heat flux measurement. On the one hand every experimental technique has its possible errors and needs to be checked and corrected. On the other hand, SEB equation should include all sensed energy sources and sinks.

Most measurements of air temperature and humidity originate from Stevenson-type thermometer screens, which can produce erroneous measurements in light winds owing to insufficient ventilation of the in-screen sensors. A field experiment to measure airflow within a Stevenson screen found mean airflow to be only 0.2 m s⁻¹, well below the 1 m s⁻¹ minimum normally assumed, and only 7 % of 10 m mean wind speeds. Implications for air temperature and humidity measurement uncertainties are discussed.

In airborne survey, dynamic flight conditions cause unequal data levels, which seriously impact airborne geophysical data analysis and interpretation. A new technique is proposed to level geophysical data in view of the image space properties. We have confirmed the reliability of the method by applying it to the airborne electromagnetic, magnetic and apparent-conductivity data. The method can automatically extract leveling errors without the participation of staff members or tie-line control.

Sensors capable of measuring rapid fluctuations are important to improve our understanding of environmental processes. Many sensors are unable to do this, due to their reliance on the transfer of the measured property, for instance a gas, across a semi-permeable barrier. We have developed a mathematical tool which enables the retrieval of fast-response signals from sensors with this type of sensor design.

We present a mobile and self-sufficient seismometer station concept for operation in polar regions. The energy supply can be adapted as required using the modular cascading of battery boxes, wind generators, solar cells, or backup batteries, which enables optimum use of limited resources. Our system concept is not limited to the applications using seismological stations. It is a suitable system for managing the power supply of all types of self-sufficient measuring systems in polar regions.

The commercial off-the-shelf (COTS) PNI RM3100 magnetometer was tested for single-event latchup (SEL) at Lawrence Berkeley National Laboratory's heavy-ion beam and did not experience any single-event effects at a linear energy transfer >75 MeV cm² mg⁻¹. Coupled with previous total ionizing dose (TID) testing at the University of Michigan and NASA Goddard Space Flight Center that showed no degradation in performance up to 150 kRad(SI), the COTS PNI RM3100 is extremely radiation tolerant.

The widespread availability of low-cost electronics has created new opportunities for affordable geophysical equipment. Electromagnetic geophysical methods allow users to examine the electrical properties of the ground. The Colorado School of Mines electromagnetic system (CSM-EM) is a proof of concept instrument capable of sensing shallow conductive objects and costs under USD 400 to build. We tested the system in a laboratory setting and validated it over a metal target outdoors.

The ability to make reliable magnetic measurements in space is very important for a broad range of applications in space science. Here, we present the design and performance of a new magnetometer that looks very promising for making stable reliable magnetic measurements in space. We show that Tesseract performs better than the traditional ring-core design in metrics that are associated with stability.

The Swarm-Echo Satellite carries two magnetometers that allow us to obtain two independent measurements of the changes that occur in the Earth's magnetic field during events such as aurora. Magnetometers must be independently calibrated to ensure they remain accurate. If no magnetic reference is available, a model magnetic field must be used. This paper discusses the method used to calibrate the magnetometers on Swarm-Echo and shows the improvements the calibration has made to the data product.