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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.

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.

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.

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.

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.

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.

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.

Using an underwater buoyancy-powered autonomous glider, we collected profiles of temperature and salinity from the ocean north-east of Barbados. Most of the temperature and salinity profiles contained staircase-like structures of alternating constant values and large gradients. We wrote an algorithm to identify these staircases. We hypothesise that these staircases are prevented from forming where background gradients in temperature and salinity are too great.

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.

The construction, operation and analysis of a spectral electrical impedance tomography (sEIT) field monitoring setup with high spatial and temporal resolution are presented. Electromagnetic induction errors are corrected, allowing the recovery of images of in-phase conductivity and electrical polarisation of up to 1 kHz.

Important topics in land–atmosphere feedback research are water and energy balances and heterogeneities of fluxes at the land surface and in the atmosphere. To target these questions, the Land–Atmosphere Feedback Observatory (LAFO) has been installed in Germany. The instrumentation allows for comprehensive measurements from the bedrock to the troposphere. The LAFO observation strategy aims for simultaneous measurements in all three compartments: atmosphere, soil and land surface, and vegetation.

MDAL is a near real-time, satellite-based surface albedo product based on the geostationary Meteosat Second Generation mission. We propose an update to the processing algorithm that generates MDAL and evaluate the results of these changes through comparison with the pre-update, currently operational MDAL product as well as reference data using different satellite-based albedo products and in situ measurements. We find that the update provides a valuable improvement.

Accurate monitoring of water in soil can improve irrigation efficiency, which is important considering climate change and the growing world population. Cosmic-ray neutrons sensors (CRNSs) are a promising tool in irrigation monitoring due to a larger sensed area and to lower maintenance than other ground-based sensors. Here, we analyse the feasibility of irrigation monitoring with CRNSs and the impact of the irrigated field dimensions, of the variations of water in soil, and of instrument design.

Overall accuracy of CO₂/H₂O data from open-path eddy-covariance systems is modeled for data analysis. The model is further formulated into CO₂ and H₂O accuracy equations for uses. Based on atmospheric physics and bio-environment, both equations are used to evaluate accuracy of ecosystem CO₂/H₂O data and, as rationales, to assess field CO₂/H₂O zero and span procedures for the systems. The procedures are assessed for measurement improvement. An impractical H₂O span while cold is found unnecessary.

In most cases, the soil water content (SWC) measurement is carried out using commercially available dielectric-permittivity-based probes such as time domain reflectometers or frequency domain reflectometers (FDR). However, these probes use transfer functions which may be inadequate in the soil concerned. Raw SWC measurement in clayey soil shows an important relative error. A simple protocol is presented, allowing for the recovery of an acceptable accuracy of the FDR SWC measurements.

The Sweeping Langmuir Probe on board the PICASSO CubeSat was designed to measure plasma parameters. Before launch, the instrument was tested in a plasma chamber. It is shown that the traditional method to interpret the data cannot be applied directly for this type of probe, and an adaptation is proposed. It is reported how, with a reduced number of data points, the plasma parameters can still be retrieved. Finally, the effects of the contamination of the probe surface are discussed.

This project aims to demonstrate the viability of the development of a concept prototype that has, as a differential, free software and hardware used in its development and operation. It thus has unique characteristics compared with commercially available equipment for signal detection, providing strong rejection of spurious electrical noise, typical of urban areas. This project is important academic contribution to open-source instrumental research.

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 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 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.

Electromagnetic sensors in a drone set-up allow a lot of movability and downscale the cost and risk typically associated with an airborne system. This paper discusses the pros and cons of our newly developed drone-towed sensor system, where we use the controlled-source electromagnetic sensor GEM-2. We conduct six different tests dealing with altitude dependency, temperature drift, transmission frequencies, T and P mode, and drone noise. Additionally, we show a data set collected with the system.

The design, characteristics, and performance of a CubeSat magnetometer board (Quad-Mag) equipped with four PNI RM3100 magnetometers is presented. The inclusion of four sensors allows a potential factor of 2 reduction in the noise floor established for an individual sensor via oversampling with multiple sensors. The Quad-Mag is shown to enable 1 nT magnetic field measurements at 1 Hz and 5.345 nT at 65 Hz using commercial off-the-shelf sensors for space applications.