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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).

This paper is dedicated to description of universal, easy-to-modify, and affordable rock slope monitoring system. Using such a system, we are able to monitor environmental variables, the rock mass 3 m subsurface zone temperature profile, and spatiotemporal joint dynamics. We observe differences between three monitored sites. To further data analyses, longer time series are needed. The data will be further used for trend analyses and thermomechanical modelling.

This paper describes a seismic dataset acquired by network of broadband sensors in Poland and technical issues related to data acquisition. We describe a new azimuth-transfer device for precise sensor orientation and apply methods for data-based orientation checking. We analyse the seismic noise level and discuss effect of geology at sites on character of seismic data and noise. We show data examples and describe methods of seismic data interpretation for studies of lithospheric structure.

Global satellite navigation systems are commonly used for timing and synchronization of instrument platforms. These system clocks periodically roll over from limitations in discrete counter math. Due to the rarity of these events (19.6 years for GPS), special consideration must be given to designing instruments intended for use in hard-to-reach locations like the Antarctic Plateau. A few best practices are presented to prevent total system failure from unexpected subsystem faults.

We reviewed eight algorithms to estimate missing values of environmental drivers and three major fluxes in eddy covariance time series. Overall, machine-learning algorithms showed superiority over the rest. Among the top three models (feed-forward neural networks, eXtreme Gradient Boost, and random forest algorithms), the latter showed the most solid performance in different scenarios.

This paper describes the development of a new multifunctional four-dimensional high-density electrical instrument based on remote wireless communication technology, for use in shallow geophysical prospecting. We carried out a lot of tests. Our design successfully addresses a number of shortcomings of such instruments currently available on the market, including bulkiness, weight, limitations in data acquisition accuracy, and difficulty of connecting to the Internet for remote monitoring.

This paper presents a brief description of the ground-based installation for the study of cosmic rays CARPET. Today there is a network of such installations located in different parts of the world. For ground-based installations, meteorological effects must be considered as they affect the data. This paper shows a technique for eliminating barometric and temperature dependences based on data for 2019–2020.

The Low Orbit Pearl Satellites measure magnetic field with high spatial coverage. Although there is no magnetic cleanliness to the satellites, the triple sensor configuration enables removal of interference. Results show they can capture the Earth’s internal as well as external fields from the magnetosphere–ionosphere current system. This study implies that a large number of small low-cost satellites without magnetic cleanliness could be the future for space magnetic exploration.

We have produced a standardised high-quality set of measurements to create definitive data for four Indonesian Geomagnetic Observatories for 2010–2018. We explain the steps taken to update the existing data collection and processing protocols and suggest improvements to further enhance the quality of the magnetic time series at each observatory. The new data will fill the gap in the western Pacific region and provide input into geomagnetic field modeling and secular variation studies.

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.

This paper presents a novel method for locating magnetic interference sources on unmanned aircraft systems (UAS) destined for aeromagnetic surveys. The technique is demonstrated in an indoor laboratory, whereas most magnetic mapping has previously been done outdoors, and is performed on four different types of UAS with their motors engaged. Sources are discussed on each UAS platform but can also be used as a point of reference for typical components that cause interference.

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.

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.

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.

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.

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.

Laser interference absolute gravimeters are high-precision gravimetry instruments. However, the error caused by self-sysetm and enviromental vibration has become the primary obstacle limiting their accuracy and stability. The present work addresses this issue by proposing a global search optimization algorithm that determines the optimal absolute value of gravity. The results evaluated by numerical calculations demonstrate that this algorithm provides a substantial anti-vibration capability.

Indoor positioning technology is used in all aspects of life. We study the positioning method of a UWB radar network. Because of the interference in the indoor environment, the UWB radar measurement data produce abnormal values. In order to eliminate the outliers, the method of fitting the known true value with the actual measured value is used to obtain the linear relationship between the true value and the measured value, so as to get the unknown true value through the measured value.

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.

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.

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.

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.

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.

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.

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 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.

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.

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.