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In times of global warming, permafrost is starting to degrade at alarming rates, requiring new and improved characterization approaches. We describe the design and test installation, as well as detailed data quality assessment, of a monitoring system used to capture natural electrical potentials in the subsurface. These self-potential signals are of great interest for the noninvasive investigation of water flow in the non-frozen or partially frozen subsurface.

Medium-frequency radars measure winds (between 55 and 100 km altitude). As part of their final year undergraduate project, the lead author used two radars in Antarctica to look at how the wind speed varied with the aim of identifying when the wind was too fast to be a real measurement. Instead, we discovered that the variance depends strongly on factors in the analysis technique rather than on natural features such as gravity waves, and that the Sun and geomagnetic activity play a role.

The baseline wander has special characteristics, such as being low frequency, large amplitude, non-periodic, and non-stationary. It is caused by the receiving coil motion and always exists in the process of data acquisition. The proposed method can be used to solve similar problems. This paper has the following highlights: (1) the method can be used to process non-periodic and non-stationary signals; (2) the method is adaptive to satisfy the stopping criterion based on the measured signal.

We developed a method to acquire dense point clouds with a low-cost Velodyne Puck lidar system, without using expensive Global Navigation Satellite System (GNSS) positioning or IMU. We mounted the lidar on a motor to continuously change the scan direction, leading to a significant increase in the point cloud density. The system was compared with a more expensive system based on IMU registration and a SLAM algorithm. The alignment between acquisitions with those two systems is within 2 m.

Continuous data of soil CO₂ efflux can improve model prediction of climate warming, and automated data are becoming increasingly available. However, aggregating chamber-based data to plot scale pose challenges. Therefore, we showed, using 1 year of half-hourly data, how using the lognormal assumption tackles several challenges. We propose that plot-scale SO₂ efflux observations should be reported together with lognormally based uncertainties and enter model constraining frameworks at log scale.

A novel airborne sensing platform is developed for meteorological measurements including variables such as components of wind velocity vector, temperature, pressure, and relative humidity. The system is called the Tethered Air Blimp (TAB). This system is deployed at a complex mining facility in northern Canada to measure dynamics of the atmosphere in various diurnal times, latitudes, longitudes, and altitudes. It measures convective, neutral, and stable boundary layers up to 150 m.

This paper describes GRUAN's strategy for a network-wide change of the operational radiosonde from Vaisala RS92 to RS41. GRUAN's main goal is to provide long-term data records that are free of inhomogeneities due to instrumental effects, which requires proper change management. The approach is to fully characterize differences between the two radiosonde types using laboratory tests, twin soundings, and ancillary data, as well as by drawing from the various fields of expertise available in GRUAN.

Based on existing ocean bottom E-field (OBE) receiver specifications, including low noise levels, low power consumption, and low time drift errors, we integrated two induction coils for the magnetic sensor and a three-axis omnidirectional geophone for the seismic sensor to assemble an ultra-short baseline (USBL) transponder as the position sensor, which improved position accuracy and operational efficiency while reducing field data acquisition costs.

GPS drifters that float down rivers are important tools in studying rivers, but they can be expensive. Recently, both GPS receivers and cellular modems have become available at lower prices to tinkering scientists due to the rise of open hardware and the Arduino. We provide detailed instructions on how to build a low-power GPS drifter with local storage and a cellular model that we tested in a fieldwork in Myanmar. These instructions allow fellow geoscientists to recreate the device.

In this paper, a low-cost, computer-aided, and geophone-based system designed to record, monitor, and analyze three-component microtremor data is presented. This system has several features such as a 200 Hz sampling frequency, text data format, and data analysis tools. The developed software undertakes many tasks such as communication between the external hardware and computer, transferring, monitoring, and recording the seismic data to a computer, and interpretation of the recorded data.

UAV-borne magnetometry has gradually become an important tool for geophysical studies. However, developing such a UAV-borne aeromagnetometry system is challenging owing to strong magnetic interference introduced by onboard electric and electronic components. One static and two dynamic experiments were conducted to understand the platform's magnetic interference. The results reveal that the strongest magnetic interference is from some current-carrying cables.

The Capon method serves as a powerful and robust data analysis tool when working on various kinds of ill-posed inverse problems. Besides the analysis of waves, the method can be used in a generalized way to compare actual measurements with theoretical models, such as Mercury's magnetic field analysis. In view to the BepiColombo mission this work establishes a mathematical basis for the application of Capon's method to analyze Mercury's internal magnetic field in a robust and manageable way.

Aerosol optical depth (AOD) is a parameter widely used in remote sensing for the characterization of atmospheric aerosol particles. AERONET was created by NASA for aerosol monitoring as well as satellite and model validation. The University of Valladolid (UVa) has managed an AERONET calibration center since 2006. The CÆLIS software tool, developed by UVa, was created to manage the data generated by AERONET photometers. The AOD algorithm in CÆLIS is developed and validated in this work.

Gravimetry studies the variations of the Earth’s gravity field which can be linked to mass changes studied in various disciplines of the Earth sciences. The gravitational attraction of the Earth is measured with gravimeters. Quantum gravimeters allow for continuous, high-frequency absolute gravity monitoring while remaining user-friendly and transportable. We assess the capacity of the AQG#B01, developed by Muquans, as a field gravimeter for hydrogeophysical applications.

A simple and autonomous ionospheric correction estimation method in SPP allows independence from external products delivering information on the ionospheric delay. The elaborated mathematical model improves navigation solutions in reference to the SPP approach with the Klobuchar algorithm and ensures results on a similar level compared to the IGS TEC map. The numerical experiment was carried out utilizing real GNSS code data and a MATLAB environment.

The CUGB-CS48DAS data acquisition system was primarily designed for seismic purposes. However, we tried to integrate the acquisition circuit for electrical purposes and implemented hardware improvements as well as software updates. Moreover, technology including narrow-band internet of things QC monitoring was also introduced. After a few field tests, the system was proven to be stable and easy to use and has a good application effect in engineering geology, mineral geology, and energy geology.

Combining short-time forecast models, standardized interfaces to a wide range of environment detectors and a flexible user access interface, CITYZER provides decision-making authorities and private citizens with reliable information about the near-future development of critical environmental parameters like air quality and rain. The system can be easily adapted to different areas or different parameters. Alarms for critical situations can be set and used to support authority decisions.

In this paper, we present a compilation of the different radiation transport codes for the Martian surface that are currently used by various space agencies and institutions. In addition, as the execution of the tasks necessary to process all of these radiation data requires a high computational processing capacity, we link it to cloud computing, which is found to be an appropriate tool regarding the required resources.

Bidirectional muographic measurements were taken at an ancient burial mound built in the beginning of the 6th century which later collapsed after a landslide caused by the 1596 Fushimi earthquake, one of the largest earthquakes over the last few centuries in Japan. The result indicated large-scale vertical cracks at the top of the mound which caused its collapse, and thus an intrinsic problem was suggested about the stability of the basic foundation of the mound before this earthquake.

In this research, we applied a ground-penetrating radar (GPR) approach for excavating the ancient archeological baptism site of the Jordan River. The GPR survey was carried out at representative locations along parallel profiles using a subsurface interface radar system. The GPR profiles revealed multiple subsurface anomalies across the study area. Many features were detected in the study area, such as a buried wall, channels and a pottery pipe at the Elijah's Hill site.

Soil gas flux describes the movement of various gases either to or from the ground. Identifying changes in soil gas flux can lead to a better understanding and detection of leakage from carbon capture and storage (CCS) schemes, diffuse degassing in volcanic and geothermal areas, and greenhouse gas emissions. Traditional chamber-based techniques may require weeks of fieldwork to assess a site. We present a new method to speed up the assessment of diffuse leakage.

Researchers are making increasing use of machine learning to improve accuracy, efficiency and consistency. During such a study of the aurora, it was noted that biases or distortions had crept into the data because of the conditions (or ergonomics) of the human trainers. As using machine-learning techniques in auroral research is relatively new, it is critical that such biases are brought to the attention of the academic and citizen science communities.

Heat pulse probes are widely used to monitor soil thermal and physical properties for agricultural and hydrological monitoring related to crop productivity, drought, snowmelt, and evapotranspiration. Changes in the effective probe spacing distance can cause measurement inaccuracy. This paper uses a novel heat pulse probe and theory to compensate for changes in effective distance, thereby enabling more accurate sensor outputs useful for forecasts and predictions of drought and flooding.

One of the four Galilean moons of Jupiter, Europa, is one of the most promising places in the solar system to find life outside Earth. For this reason, the space science community is currently focused on exploring it. One of the main difficulties of such a task is the harsh radiation environment caused by the radiation belts of Jupiter. In this paper, we present results for a magnetic field sensor being exposed to radiation levels similar to those expected at the surface of Europa.

We propose a gradiometer-based technique for cleaning multi-sensor magnetic field data acquired on board spacecraft. The technique takes advantage on the fact that the maximum-variance direction of many AC disturbances on board spacecraft does not change over time. We apply the proposed technique to the SOSMAG instrument on board GeoKompsat-2A. We analyse the performance and limitations of the technique and discuss in detail how various disturbances are removed.

The transient electromagnetic method (TEM) is widely used for mapping subsurface resistivity structures, but data are inevitably contaminated by noise from various sources including radio signals in the very low frequency (VLF) 3–30 kHz band. We present an approach where VLF noise is effectively suppressed with a new post-processing scheme where boxcar gates are combined into semi-tapered gates. The result is a 20 % increase in the depth of investigation for the presented test survey.

A new multicomponent electrical field observation system based on an autonomous underwater vehicle (AUV) was introduced for the measurement of seafloor self-potential. The system was tested in a lake and the multicomponent self-potential data were collected. The new SP system can be applied to marine SP observations, providing an efficient and low-noise SP acquisition method for marine resources and environmental investigations.

The systematic error of calibrated fluxgate magnetometer data is studied for a spinning spacecraft. The major error comes from the offset uncertainty when the ambient magnetic field is low, while the error represents the combination of non-orthogonality, misalignment to spacecraft reference direction, and gain when the ambient field is high. The results are useful in developing future high-precision magnetometers and an error estimate in scientific studies using magnetometer data.

The Blue Nile Basin is of vital importance for the whole Nile Basin. The investigation of the impact of climate change on this basin is essential. The Blue Nile Basin annual and monthly temperatures were investigated. Spatial and temporal patterns of changes in extreme temperatures are investigated using 10 meteorological stations' data for the period 1950–2018. The investigation showed that climate change increased temperatures in the basin.

Geographic coordinates (latitude and longitude) are widely used in geospatial applications, and terrains are often defined by regular grids in geographic coordinates. However, because of convergence of lines of longitude near the poles there is oversampling in the latitude (zonal) direction. Also, there is no standard way of defining a hierarchy of grids to consistently deal with data having different spatial resolutions. The proposed global geographic grid system solves both problems.

Current borehole receivers only measure a single parameter of the magnetic field component, which does not meet the special requirements of controlled-source electromagnetic (CSEM) methods. This study proposes a borehole electromagnetic receiver that realizes synchronous acquisition of the vertical electric field component and three-axis orthogonal magnetic field components. Results of the experiments show that our system functioned adequately and that high-quality CSEM signals were obtained.

In order to meet the needs of geophysical exploration, the requirements of intelligent and convenient exploration instruments are realized. From the perspective of software, this research combines today's wireless transmission technology to integrate applications into mobile phones to realize remote control of field operations. It provides a new idea for geophysical exploration.