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In dry-stack tailing ponds with high fine-grained content, a high long-term saturation line can lead to dam failure. Electroosmotic consolidation is an effective method for reducing dam saturation lines. However, traditional electrodes have low corrosion resistance and poor contact, which limits the development of electroosmotic drainage technology for tailings. In this study, an electroosmotic drainage device, an electrokinetic geosynthetic (EKG) electrode, was designed. The influence law of the electrode material, potential gradient, and number of electrodes on the water drainage, current, and resistance was analyzed. The results show that the EKG electrode has excellent corrosion resistance, with its weight loss after electroosmosis, water drainage, and equivalent allowable current being 1.67%, 122%, and ∼2.3 times that of a copper electrode, respectively. Furthermore, it was found that the optimal potential gradient was 1.2 V/cm, and the water drainage cannot be improved by an exceedingly high potential gradient. The current pathway in the test box was in parallel, and the water drainage increased to 410% and the contact resistance decreased by 83% when the number of electrodes was four. These results and novel methodology provide new ideas for EKG electrode design and represent an effective method for saturation line control in gold tailing ponds. • Study is beneficial for the application of EKG electrodes in tailings electroosmosis. • This study designed a new corrosion-resistant electrodynamic geosynthetic electrode. • An electroosmotic test device that can automatically collect data was created. • The performance of the EKG electrodes was compared with that of copper electrodes. • The variation of electroosmotic effect at different number of electrodes was studied. [ABSTRACT FROM AUTHOR]

Soil electrical conductivity has been extensively investigated in the fields of precision agriculture, geophysical mapping, and soil property mapping. However, the understanding of soil electro-osmotic conductivity is currently limited. Comprehensive insight into soil electro-osmotic conductivity is crucial for an accurately designing the electro-osmosis technique, which is widely accepted as a highly promising method for disposing soft soils with high water content. To fill this knowledge gap, a series of laboratory experiments was conducted using Hangzhou sludge. Four factors, including electrode material, potential gradient, soil water content, and pore water salinity, were investigated in terms of their influence on electrical conductivity of the electro-osmotically treated soil. Results show that during the electro-osmosis process, the soil electro-osmotic conductivity initially slightly increases and then decreases. The impact of electrode materials on soil electro-osmotic conductivity was minimal, whereas a high potential gradient was observed to generate low soil electro-osmotic conductivity. Furthermore, this conductivity was found to be linearly correlated with real-time water content. The slope of the correlation was also significantly influenced by the initial water content of the soil. Under different levels of pore water salinity, the soil electro-osmotic conductivity first increases to a peak and then decreases to a residual value. The soil electro-osmotic conductivity are observed to have a linear relationship with pore water salinity. These implications are closely linked to the soil conduction mechanism. Based on the foregoing findings, limiting the calculations to the pore water-induced conduction during the main stages of the electro-osmosis process is recommended. Furthermore, linear predictive relationships between soil electro-osmotic conductivity and the corresponding level of soil water content as well as between the soil electro-osmotic conductivity and the pore water salinity should be used in simplified calculation of the electro-osmosis process. The parameters involved in these relationships can be accurately determined through laboratory experiments. [ABSTRACT FROM AUTHOR]

Abstract Surface atmospheric electric field (AEF) measurements were conducted using a Kelvin water dropper equalizer by the Japan Meteorological Agency's geomagnetic observatory at Kakioka, Ibaraki Prefecture, Japan, from 1929 to February 28, 2021. To obtain AEF data successive to the water dropper measurement, we independently installed the field mills at Kakioka. In this present study, we estimated the calibration coefficients based on comparisons between the water dropper and the field mills through parallel observations over 3 days. The results revealed that the new observations could be regarded as continuous data. Our new data from the field mills in this study have begun the process of being distributed in GLObal Coordination of Atmospheric Electricity Measurements (GloCAEM) as both archived and real‐time data in 1 min and 1 s samplings.

Surface atmospheric electric field (AEF) measurements were conducted using a Kelvin water dropper equalizer by the Japan Meteorological Agency's geomagnetic observatory at Kakioka, Ibaraki Prefecture, Japan, from 1929 to February 28, 2021. To obtain AEF data successive to the water dropper measurement, we independently installed the field mills at Kakioka. In this present study, we estimated the calibration coefficients based on comparisons between the water dropper and the field mills through parallel observations over 3 days. The results revealed that the new observations could be regarded as continuous data. Our new data from the field mills in this study have begun the process of being distributed in GLObal Coordination of Atmospheric Electricity Measurements (GloCAEM) as both archived and real‐time data in 1 min and 1 s samplings. [ABSTRACT FROM AUTHOR]

This study conducted experimental investigations into the effects of electrode material and potential gradient on the effectiveness of electro-osmotic consolidation (EO) in strengthening soft soils. Seven laboratory tests were conducted on high-water-content marine clayey soils through EO. In these experimental tests, four different types of electrodes made of steel, copper, aluminum, and composite carbon fiber (CCF) were employed in four tests each to evaluate the consolidation effectiveness. Additionally, four tests, one was the comparitive study for different eletrode materials, were carried out to determine the optimal gradient for the EO using CCF electrode. Several critical properties of the tested soils were examined and evaluated in this study, including the effective voltage utilization, potential distribution, water discharge, discharge rate, energy consumption, and soil bearing capacity. The test results indicated that the CCF electrode had superior performance in water discharge, discharge rate, and average soil water content compared to metal electrodes. Furthermore, CCF led to uniform enhancement of soil strength, with treated soil bearing capacities 6.3 to 12 times higher than initial values, and 1.9 to 2.5 times higher than those attained with metal electrodes. Additionally, an effective potential gradient of 1 V/cm was identified for the EO with the CCF electrode, providing a higher discharge rate and a larger soil strength in a uniform distribution. Moreover, the use of CCF electrode significantly reduced corrosion compared to metal electrodes during the consolidation process, further contributing to improved consolidation efficiency. This study offers valuable insights and recommendations for the utilization of CCF in marine clayey soils, effectively addressing the challenges posed by electrode corrosion and high energy consumption in EO applications. [ABSTRACT FROM AUTHOR]

Atmospheric electric fields (AEFs) have recently been proposed to link to biogeochemical processes below the Earth’s surface by means of a charge separation. Despite the potential importance of such a process, up to now we almost completely lack the relevant measurements. Here, we extend the database with 2 months of concurrent soil redox and atmospheric electric field measurements. It appears that the changes that occur in the order of days in soil redox are at periods anticorrelated with the logarithm of the positive values of the AEF. However, weather conditions might be driving the anticorrelation rather than a direct link, as the synoptic weather conditions appear to influence soil redox. Soil redox does not respond to changes in the AEF that are of shorter duration, either minutes or several hours, except in some cases of very negative AEFs or very high field strengths in the presence of moderate rainfall. In such a case, the variation in soil redox could be associated with a mechanism that transfers charge to the ground or brings ions towards the ground’s surface. To reach firmer conclusions on the effect of the AEF on soil redox, we need to extend the range of collocated soil redox and AEF measurements so that they cover at least one year.

Abstract The suppression of high‐energy cosmic rays, known as Forbush decreases (FDs), represents a promising factor in influencing the global electric circuit (GEC) system. Researchers have delved into these effects by examining variations, often disruptive, of the potential gradient (PG) in ground‐based measurements taken in fair weather regions. In this paper, we aim to investigate deviations observed in the diurnal curve of the PG, as compared to the mean values derived from fair weather conditions, during both mild and strong Forbush decreases. Unlike the traditional classification of FDs, which are based on ground level neutron monitor data, we classify FDs using measurements of the Alpha Magnetic Spectrometer (AMS‐02) on the International Space Station. To conduct our analysis, we employ the superposed epoch method, focusing on PGs collected between January 2010 and December 2019 at a specific station situated at a low latitude and high altitude: the Complejo Astronómico El Leoncito (CASLEO) in Argentina (31.78°S, 2,550 m above sea level). Our findings reveal that for events associated with FDs having flux amplitude (A) decrease ≤10%, no significant change in the PG is observed. However, for FDs with A > 10%, a clear increase in the PG is seen. For these A > 10% events, we also find a good correlation between the variation of Dst and Kp indices and the variation of PG.

This study conducted experimental investigations into the effects of electrode material and potential gradient on the effectiveness of electro-osmotic consolidation (EO) in strengthening soft soils. Seven laboratory tests were conducted on high-water-content marine clayey soils through EO. In these experimental tests, four different types of electrodes made of steel, copper, aluminum, and composite carbon fiber (CCF) were employed in four tests each to evaluate the consolidation effectiveness. Additionally, four tests, one was the comparitive study for different eletrode materials, were carried out to determine the optimal gradient for the EO using CCF electrode. Several critical properties of the tested soils were examined and evaluated in this study, including the effective voltage utilization, potential distribution, water discharge, discharge rate, energy consumption, and soil bearing capacity. The test results indicated that the CCF electrode had superior performance in water discharge, discharge rate, and average soil water content compared to metal electrodes. Furthermore, CCF led to uniform enhancement of soil strength, with treated soil bearing capacities 6.3 to 12 times higher than initial values, and 1.9 to 2.5 times higher than those attained with metal electrodes. Additionally, an effective potential gradient of 1 V/cm was identified for the EO with the CCF electrode, providing a higher discharge rate and a larger soil strength in a uniform distribution. Moreover, the use of CCF electrode significantly reduced corrosion compared to metal electrodes during the consolidation process, further contributing to improved consolidation efficiency. This study offers valuable insights and recommendations for the utilization of CCF in marine clayey soils, effectively addressing the challenges posed by electrode corrosion and high energy consumption in EO applications.

Abstract The Kakioka Magnetic Observatory (KMO) of the Japan Meteorological Agency (JMA) made atmospheric electric field observations at Kakioka and Memambetsu beginning in 1929 and 1949, respectively, and ending in February 2021 and December 2010, respectively. The digital numerical data are available on the KMO website, although not all observation periods are covered. In this article, we introduce the available datasets and summarize the metadata regarding the observations, such as measurement instruments, maintenance methods and data processing.

Atmospheric electricity parameters (AEP) measurements from Antarctica predominantly feature either the potential gradient (PG) and/or air‐Earth current (AEC) density. We report for the first time simultaneous measurements of the bipolar ions concentration/conductivity, PG, and AEC density. AEP measurements were carried out at Maitri (70.8°S, 11.8°E) from December 2018 to November 2019. We formulated a few criteria, irrespective of the weather conditions, to select the electrically quiet days and some additional criteria based on the conductivity measurements to discern globally representative data (GRD) from such days. The measurements of the PG and AEC density over the Antarctic plateau demonstrated the diurnal curves similar to the Carnegie pattern, which represents the global thunderstorms and electrified shower clouds (ESCs) occurring on different continents and oceans, we regard the data having such trend as GRD. We found significant variability in the concentration of small bipolar ions/conductivity in the austral summer which in turn affects GRD. However, the concentration of bipolar ions is nearly consistent at ∼250 negative ions cm−3 and ∼300 positive ions cm−3 in winter and enhances the probability of GRD. Such differences can arise out of the prevalent planetary boundary layer processes in the two seasons. When the PG varied between ∼50 Vm−1 and ∼150 Vm−1 and the maximum range of conductivity variations was ∼0.2 × 10−14 ℧ m−1, the AEPs represented the signatures of the global thunderstorm and ESC activities. Plain Language Summary: Monitoring of the atmospheric electricity parameters is a simple technique to monitor global thunderstorm activity and electrified shower clouds. For this, the data need to be free from local disturbances. Obtaining such data in Antarctic Plateau was found to be successful. On the other hand, the coastal Antarctic stations, experience local or regional contributions in it. This paper attempts to provide some techniques to obtain globally representative data (GRD). This paper suggests that the diurnal variation of the concentration of bipolar small ions strongly impacts the GRD. Therefore a day free from the diurnal variation of the concentration of bipolar ions is essential to discern the global signals. The winter season appears to be a better season for this as the summer season experiences mild convection activity that causes local and regional electrical signals that contaminate the data. Key Points: Atmospheric electrical conductivity is the key parameter to discern globally representative data (GRD) over the Maitri, AntarcticaGRD is discernible on a day when conductivity is consistent, and such days are most common in local winterIn the austral summer, the planetary boundary layer (PBL) processes produce local electrical signals that interfere with the global signals [ABSTRACT FROM AUTHOR]

Currently, the impressed current cathodic protection with deep‐well anode beds has been found that the surface casing was charged. In this study, 13 deep‐well anode beds were selected randomly to investigate whether their surface casings were electrified. Possible causes of the electrification of surface casings are also discussed. A numerical model for simulating the geoelectric field of a representative deep‐well anode bed with an electrified surface casing was established and validated by data from on‐site testing. The difference in the interference characteristics between situations with charged and uncharged casings was also discussed. The results showed that 30.7% of deep‐well anode beds had electrified surface casings. The leading root causes may be that the anode cable had been damaged unexpectedly during the construction process or the electrical resistance between the anodes and the surface casing had been reduced dramatically. The peak potential gradient and comprehensive interference intensity were about 20 times and 3–6 times, respectively, those in situations where the casing was uncharged. A polyvinyl chloride surface casing is, therefore, recommended in deep‐well anode beds. Reliable electrical insulation should be implemented if steel casings are used. Furthermore, regular electrification tests on steel surface casings should be conducted during completion acceptance and daily operation. [ABSTRACT FROM AUTHOR]

The precipitation of calcium carbonate induced by Sporosarcina pasteurii (S. pasteurii) has garnered considerable attention as a novel rock and soil reinforcement technique. The content and structure of calcium carbonate produced through this reaction play a crucial role in determining the rocks' and soil's reinforcement effects in the later stages. Different potential gradients were introduced during the bacterial culture process to enhance the performance of the cementation and mineralization reactions of the bacterial solution to investigate the effects of electrification on the physical and chemical characteristics, such as the growth and reproduction of S. pasteurii. The results demonstrate that the concentration, activity, and number of viable bacteria of S. pasteurii were substantially enhanced under an electric field, particularly the weak electric field generated by 0.5 V/cm. The increased number of bacteria provides more nucleation sites for calcium carbonate deposition. Moreover, as the urease activity increased, the calcium carbonate content generated under an electric potential gradient of 0.5 V/cm surpassed that of other potential gradient groups. The growth rate increased by 9.78% compared to the calcium carbonate induced without electrification. Significantly, the suitable electric field enhances the crystal morphology of calcium carbonate and augments its quantity, thereby offering a novel approach for utilizing MICP in enhancing soil strength, controlling water pollution, and mitigating seepage. These findings elevate the applicability of microbial mineralization in engineering practices. [ABSTRACT FROM AUTHOR]

Surface measurements of the atmospheric electric field at the University of Kashmir, Srinagar (34° 13′ N, 74° 83′ E, 1585 m amsl) and Gulmarg (34° 05′ N, 74° 39′ E, 2617 m amsl) in the Kashmir Valley from March 2018 to August 2020 are analyzed to understand the behavior of the electric field during fair-weather, precipitation, snowfall, and fog conditions. The maximum thunderstorm activity observed in May, June, and July is attributed to the higher amount of moisture transport by western disturbances during May followed by the monsoon wind in June and July from the Bay of Bengal and the Arabian Sea. Based on the observations, in addition to the ordinary thunderstorms, several severe convective thunderclouds associated with the positive end-of-storm oscillations and inverted dipole structured clouds are also reported and explained. In addition, the observation of raindrop-induced field and periodic oscillations (90-min) in the potential gradient are explained in terms of the impact of the charge carried by the raindrops during precipitation, splashing on the ground and suspended snowflakes in snowfall episodes. [ABSTRACT FROM AUTHOR]

Characterizing the interaction between meteorological variables such as humidity, wind speed, cloud cover, and precipitation with the atmospheric electric field is vital for improving the nowcast of extreme weather events such as heavy precipitation. With this aim, we provide minute-scale electric field observations in southern Israel. These were taken during low-pressure weather systems in winter, often termed 'Cyprus Lows.' We focus only on precipitating ('wet') events, where rain was measured at the surface during and after the cold front's passage. The mean |PG| values for 'wet' Cyprus Lows are higher (Hundreds to thousands V m−1) compared with the mean fair-weather values (∼100–200 V m−1, and exhibit a sharp and rapid increase of the |PG| of up to tens of V m−1 min−1 during the arrival of the cold front and hundreds of V m−1 min−1 during precipitation. Then, we analyzed selected case studies in detail. The response of the |PG| to thunderstorm clouds, i.e., Cumulonimbus, is an increase to values of thousands of V m−1. The temporal evolution of the |PG| allowed us to identify the type of cloud and its life cycle stage. We suggest that using state-of-the-art 1 Hz measurements of the |PG| and deducing cloud patterns at strategic locations, such as in arid regions like southern Israel, may improve the nowcasting capabilities of localized heavy precipitation events. • Meteorological Interaction : Exploring the relationship between Met-parameters with the atmospheric electric field to improve the forecast • Observational Data : High-resolution electric field observations were during winter low-pressure systems • Electric Field Variation - Wet : Mean potential gradient values 'wet' events are significantly higher than fair weather values. • Electric Field Variation - Wet : Mean potential gradient values 'wet' events are significantly higher than fair weather values. • Cloud Analysis : potential gradient responses to storm clouds reaching thousands of V m−1, allowing identification of cloud types and life cycle stages. • Now-casting and Global Applicability : The methodologies and findings may enhance the now-casting of localized heavy precipitation events. [ABSTRACT FROM AUTHOR]

One of the urgent tasks in the design of hybrid integrated circuits (HICs) is the construction of adapter-attenuators of film absorbing elements that provide a wide range of attenuations with the given values of input and output resistances. Known versions of adapter-attenuators based on homogeneous and piecewise-homogeneous resistive films provide a resistance transformation ratio of not more than 3 and 10–12, respectively. The paper proposes promising topologies of adapter-attenuators for HICs with an almost optimal profile of the input and output contacts. It is shown that these topologies make it possible not only to obtain a wide range of transformation ratios (more than 100) but also to reduce the maximum values of the potential gradient and power density by a factor of 10 to 30. When calculating the rectangular topology, the apparatus of the theory of functions of a complex variable is used. The optimized topology of adapter-attenuators for HICs is modeled by the finite element method implemented in the Elcut software package. The calculated ratios and graphs that show the relationship between attenuation, the transformation ratio, gain in the potential gradient, and power density depending on the ratio of the dimensions of the film element and the specific resistances of the resistive films used are presented. The features of fitting adapter-attenuators are considered. The results obtained are important for the operation of the film element of adapter-attenuators for well logging in the pulsed mode. [ABSTRACT FROM AUTHOR]

Ground-based measurements of the electric field from a station located in the arid Negev region of southern Israel have been conducted continuously since 2013. We present here results of observations of the electric field (Potential Gradient, PG) variability during 22 cloudy days, with varying cloud types and cloud base heights, and compare the measured values with the mean fair-weather PG. The results show an increase of PG (~+10 to +70 V m−1) from mean fair weather values during times of low clouds. During times of mid-altitude (alto) clouds or during a superposition of low and high clouds, there were small departures in the PG values (~0 to −30 V m−1) compared to mean fair weather PG values. During times of high-altitude cirrus clouds there is a clear decrease of the PG (~−40 to −90 V m−1). The data was compared with the Israeli meteorological service cloud data and with MODIS 7 satellite cloud top height maps. In addition, AERONET aerosol optical depth values and wind speed magnitude from a local meteorological station were analyzed. [ABSTRACT FROM AUTHOR]

Distinct differences in electrical characteristics of the atmosphere are observed during clear and foggy laden air. The presence of droplets in the air causes the removal of natural cluster ions and hence, a change in the electrical properties, which is useful for fog detection, and potentially fog forecasting. In this study, we report on some of the first electrical measurements conducted during fog in the United Arab Emirates (UAE). The analysis indicates that the Potential Gradient (PG) values observed during fog in the UAE were substantially higher than those previously reported in the literature (ranging from −1247 V/m to 1400 V/m). Furthermore, the PG during fog was often negative, with 93% of cases recording negative PG values (with median PG value of −397 V/m), particularly during wintertime fog events. A comparison with fog measurements conducted in the UK showed a stark contrast in PG behaviour between the two sites, with only positive PG values reported during fog in the UK (as is the case for the majority of PG fog studies reported in the literature), and higher PG variability in the UAE fogs. It is hypothesized that the unusual polarity of PG observed in UAE fog events may be attributed to the deposition of fog droplets, during which positive charges are transported from the top of the fog layer downwards towards the surface, thereby modifying PG. This deposition process is expected to be particularly active during the latter stages of the fog, when the droplet size distribution has fully evolved. • Potential gradient (PG) measurements conducted during fog from a desert site are reported for the first time from the United Arab Emirates (UAE). • Negative PG was observed during 93% of fogs in the UAE, in contrast to most previously reported PG observations during fog in the literature. • The PG in UAE fogs is found to have a larger magnitude and variability than PG in UK fogs. • In contrast to what is expected from current theory, no clear correlation was witnessed between PG and visibility during fogs in the UAE. [ABSTRACT FROM AUTHOR]

In this study, the response of atmospheric electrical and meteorological variables at three different sites of Argentina are studied during the total solar eclipse of December 14, 2020: Valcheta (100% darkening), Buenos Aires (73%) and El Leoncito (71%). The reduction in solar irradiance caused by the solar eclipse was expected to directly affect the near-surface electric field, known as the potential gradient (PG), through a reduction in turbulence and an increase in air conductivity. From the analysis of the observed meteorological parameters (temperature, relative humidity, and wind), no effects on the PG were observed that can be unequivocally attributed to this event based solely on boundary layer dynamics. The prevailing synoptic situation altered the response that the boundary layer could have given, namely, a clear drop in radiation, particularly at Valcheta, which was very close to a frontal zone and had occasional cloud coverage and reports of atmospheric suspended dust. PG measurements at Valcheta during the eclipse showed PG values several orders of magnitude higher and of opposite sign to the global daily mean fair weather (FW) PG curve and the local FW-PG curves calculated at CITEDEF (940 km away) and CASLEO (1200 km away). The PG values at Valcheta were shown to be more closely related to disturbed weather conditions than FW. On the contrary, at the other two locations studied, CITEDEF and CASLEO, further north and more distant from the frontal zone, the observed PG values on the day of the eclipse showed a higher consistency with the local daily mean FW-PG curves. A comparison between the FW-PG local curves at these two sites and the evolution of PG during the day of the eclipse, however, reveals a drop in PG values during the eclipse.

In the present study, the atmospheric electric field observations are reported at Gulmarg station, Kashmir (34°05′N; 74°42′E) for a period of 1 year: June 2019–May 2020. The observation site is situated in an area with high thunderstorm activity and very high radon concentration. Diurnal characteristics of PG are explained with electrode effect under summer/dry surface conditions and evaporation effect under winter/wet surface conditions associated with sunrise. The latter effect is highly responsible for the diurnal peak of PG observed in afternoon (1300 LT) hours along with the water vapour pressure under low temperature. Similarly, excess positive charges found at the electrode layer shift the diurnal peak to an earlier time ~1000–1100 LT under turbulent exchange from the surface. Therefore, the annual mean curve is the resultant of these two effects that act in different seasons. In addition, the annual diurnal variation of the potential gradient is in agreement with some other continental stations having two maxima and higher values of PG during the winter months. The secondary diurnal maximum (2000 LT) is likely due to African thunderstorm activity being reflected strongly at our measurement site. Comparison of our results with Carnegie leads to a weak correlation between the two, which is due to the difference in the nature of observation sites, while a comparison with the observations of B N Raina (August 1970–October 1973) at the same observatory reveals a similar nature of PG variation. Finally, simple correlation plots of PG with meteorological parameters and radon concentration have been shown. The results indicate that radon concentration and meteorological parameters like temperature, relative humidity in addition to water vapour pressure are important local factors influencing the surface PG measurements at our site. [ABSTRACT FROM AUTHOR]

In this paper, the electrochemical modification of lean coal samples with potential gradients of 1 V/cm, 2 V/cm and 4 V/cm, gas adsorption desorption test of coal samples before and after modification, and the change of pore structure and surface group of coal samples before and after modification were analyzed by low temperature liquid nitrogen adsorption test and infrared spectrum test. The results show that: the saturated adsorption capacity of unmodified lean coal sample is 30.030 mL/g, the Langmuir pressure of unmodified lean coal sample is 0.876 MPa, the final desorption rate of unmodified lean coal sample is 83.204%. After electrochemical modification with potential gradients of 1 V/cm, 2 V/cm and 4 V/cm, the saturated adsorption capacity of coal sample is 29.239 mL/g, 28.329 mL/g and 26.667 mL/g,and the Langmuir pressure of coal sample is 0.932 MPa, 1.042 MPa and 1.048 MPa respectively,the final desorption rate of coal sample is 84.235%, 85.541% and 87.840% respectively; the larger the potential gradient, the smaller the specific surface area of the modified coal sample, the larger the average pore diameter, and the more the number of oxygen-containing functional groups, the better the effect of inhibiting gas adsorption and enhancing gas desorption.

Abstract High‐energetic charged particles, such as solar protons, and phenomena such as Forbush decreases are eligible candidates to affect the global electric circuit. These effects have been studied by analyzing disturbances of the potential gradient in ground‐based measurements in fair weather regions. In this paper, we investigate deviations in the potential gradient diurnal curve, during solar proton events, and Forbush decreases, from the mean values obtained in fair weather conditions. In each situation, we select only events which are not accompanied or followed by the other. Using the superposed epoch analysis, in order to enhance the visualization of small effects, we study the potential gradient data recorded between January 2010 and December 2019 at two stations located at low and middle‐latitudes, and at two different altitudes: the Complejo Astronómico El Leoncito (CASLEO), Argentina: 31.78°S, 2550 m a.s.l., and the Geophysical Observatory in Świder (SWIDER), Poland: 52.12°N, 100 m a.s.l., respectively. For intense solar proton events (>100 MeV) we found a statistically significant increase of the potential gradient after solar proton events recorded at CASLEO and no such deviation in the potential gradient recorded at SWIDER. For Forbush decrease events (greater than 4%), no significant deviation of the potential gradient after the start of the event was found in both stations, however for very intense Forbush decreases (>7%) we found an increase of the potential gradient recorded at CASLEO.

Electric field measurements at Vostok station in Antarctica reveal that the El Niño—Southern Oscillation (ENSO) has a statistically significant effect on the global electric circuit, as earlier predicted by simulations. Analysis of 10 October‐February periods during 2006–2016 indicates that the shape of the diurnal variation of the surface electric field is significantly different for El Niño and La Niña years, with an especially pronounced deviation during the super El Niño of 2015/16. During strong El Niños the potential gradient relative to the diurnal mean is generally higher than usual around 8:00–14:00 UTC and lower than usual around 16:00–0:00 UTC; La Niñas are characterized by the opposite behavior. Simulations with the Weather Research and Forecasting model imply that the observed patterns are the result of changes in the global distribution of electrified clouds over the Pacific Ocean, Maritime Continent, and South America during ENSO events. Plain Language Summary: The El Niño—Southern Oscillation (ENSO) is one of the most remarkable modes of climate variability on Earth. Being made up of irregularly alternating warm (El Niño) and cold (La Niña) phases, the ENSO affects atmospheric circulation, global temperature and rainfall patterns, agriculture, and economic output. Recent simulations have suggested that changes in global convection patterns due to ENSO should also affect surface atmospheric electric fields and currents in remote regions of the planet. Here, we present electric field measurements performed during 2006–2016 at Vostok station in the Antarctic that reveal clear patterns related to ENSO as earlier predicted by simulations. Measurements show that the shape of the diurnal variation of the surface electric field is significantly different for El Niño and La Niña years (with an especially pronounced effect during the super El Niño of 2015/16), which, according to simulations, is the result of changes in the global distribution of electrified clouds over the Pacific Ocean, Maritime Continent, and South America during ENSO events. This provides further evidence of the influence of climate fluctuations on the Earth's global electromagnetic environment. Key Points: Electric field measurements in Antarctica show that strong El Niños and La Niñas consistently impact the atmospheric global circuitFor the super El Niño event of 2015/16, the anomalies in the global electric circuit are especially pronouncedSimulations show that the observed effect is due to changes in deep convection over the Pacific Ocean, Maritime Continent, and South America [ABSTRACT FROM AUTHOR]

Static electric fields in the atmosphere are increasingly recognized as interacting with various organisms over several levels of biological organization. Recently, a link between atmospheric electrical variations and biogeochemical processes has been established in the context of open fields, yet biological structures like trees produce substantial alterations in atmospheric electric properties. Here, we assess whether these structural changes affect the dynamics of the electrical landscape and its relation to geochemical processes. To this end, we theoretically assess how trees alter their surrounding electric fields and empirically compare the temporal dynamics of atmospheric potential gradients, positive ions in the near-ground level atmosphere and soil electrochemical properties in an open field and under a tree. The developed model of electric fields around trees provides insight into the extent to which trees shield the underlying electric landscape, revealing that a substantial increase in atmospheric potential gradient only marginally affects the electric field under the canopy. We further show that soil electrochemical properties are tied to the temporal dynamics of positive ion in the near-ground level atmosphere, and that the presence of a tree reduces the temporal variability in both ground level positive ion concentrations and soil redox potential. This suggests that a tree can alter the temporal variability in atmospheric electricity and soil electro-chemistry, thereby likely indirectly influencing soil microorganisms and processes as well as electro-sensitive organisms that perceive and utilize atmospheric electric fields.

• Atmospheric Potential Gradient (PG) is presented for three local stations. • The results reveal double oscillation and deviates from the Carnegie curve. • Mountainous station Muzaffarabad shows higher PG in comparison to other local stations mainly due to "Austausch Layer Effect". • Meteorological parameters (temperature, relative humidity) have great influence on the atmospheric PG. • Global comparison exhibits two distinct peaks with different timings and amplitude. In this research work, we have performed comparative diurnal variations of atmospheric Potential Gradient (PG) of fair-weather days by using the data of three stations installed in Northern, Pakistan for the year 2018. We investigated the impact of both local and global factors and meteorological parameters in the diurnal variation of atmospheric Potential Gradient on the annual and seasonal time scale. We observed two peaks, primary and secondary. This is because of the land-based measurements of annual and seasonal variations. The annual average curve of Potential Gradient of all three stations: Islamabad (CES), Muzaffarabad (MZF), and Balakot (BKT) demonstrated a notable deviation from the standard oceanic Carnegie curve. The atmospheric Potential Gradient variations are due to numerous meteorological factors e.g., air pollution, humidity, aerosol particles, fog, and temperature. Among three stations, the MZF station is located in highland (mountainous) and it demonstrated a higher atmospheric Potential Gradient. We further differentiate the results of our three stations with global results for authenticity and observed coherence between them. In addition, a positive correlation of fair-weather Potential Gradient is observed with temperature and a notable correlation between relative humidity and atmospheric Potential Gradient for all the three observatories. [ABSTRACT FROM AUTHOR]

Detection of the oil–water encroachment front is of great importance to water injection of oil reservoirs. In borehole-to-surface electrical imaging (BSEI), a high-power direct current is applied into a borehole through a well case and the electric potential on the surface, which is affected by the subsurface electrical change, is measured. However, further accurate interpretation of BSEI data is difficult due to the weak surface response, deep target layer, long inversion time, and uncertainty in unconstrained inversion. Therefore, a new method to enhance the surface response of the anomalous body and a new three-dimensional inversion approach based on the damped least-squares method are proposed. Simulation of the water injection and fracturing process was modeled in three dimensions using the finite difference method and the incomplete Cholesky conjugate gradient method. The inversion approach was applied by using the log data to construct a layered resistivity model and constrain the inversion. The forward modeling results suggest that the electric potential gradient can enhance the response of electrical variations in the target layer and help estimate the water injection direction, depending on the distance of electrical anomalies and the current source. In actual water injection monitoring, the BSEI inversion results suggest that layered resistivity model constrained three-dimensional inversion can improve the precision and accuracy of the resistivity inversion results and outline the water injection channeled to the adjacent wells. [ABSTRACT FROM AUTHOR]

Previous research has shown that the study of the global electrical circuit can be relevant to climate change studies, and this can be done through measurements of the potential gradient near the surface in fair weather conditions. However, potential gradient measurements can be highly variable due to different local effects (e.g., pollution, convective processes). In order to try to minimize these effects, potential gradient measurements can be performed at remote locations where anthropogenic influences are small. In this work we present potential gradient measurements from five stations at high latitudes in the Southern and Northern Hemisphere. This is the first description of new datasets from Halley, Antarctica; and Sodankyla, Finland. The effect of the polar cap ionospheric potential can be significant at some polar stations and detailed analysis performed here demonstrates a negligible effect on the surface potential gradient at Halley and Sodankyla. New criteria for determination of fair weather conditions at snow covered sites is also reported, demonstrating that wind speeds as low as 3 m/s can loft snow particles, and that the fetch of the measurement site is an important factor in determining this threshold wind speed. Daily and seasonal analysis of the potential gradient in fair weather conditions shows great agreement with the “universal” Carnegie curve of the global electric circuit, particularly at Halley. This demonstrates that high latitude sites, at which the magnetic and solar influences can be present, can also provide globally representative measurement sites for study of the global electric circuit.

The atmosphere is host to a complex electric environment, ranging from a global electric circuit generating fluctuating atmospheric electric fields to local lightning strikes and ions. While research on interactions of organisms with their electrical environment is deeply rooted in the aquatic environment, it has hitherto been confined to interactions with local electrical phenomena and organismal perception of electric fields. However, there is emerging evidence of coupling between large- and small-scale atmospheric electrical phenomena and various biological processes in terrestrial environments that even appear to be tied to continental waters. Here, we synthesize our current understanding of this connectivity, discussing how atmospheric electricity can affect various levels of biological organization across multiple ecosystems. We identify opportunities for research, highlighting its complexity and interdisciplinary nature and draw attention to both conceptual and technical challenges lying ahead of our future understanding of the relationship between atmospheric electricity and the organization and functioning of biological systems. [ABSTRACT FROM AUTHOR]

We present an analysis of the impact of circulation weather types (CT) on a factor that might influence biological systems and the human condition, the electric state of the atmosphere. We present results on the influence of CT to the magnitude, the direction (positive or negative), the fluctuation magnitude, and the short-term peaks of the atmospheric electric field (potential gradient, PG), using data from a station in Greece. CTs with high vorticity centers over Greece are associated with high positive and negative excursions of the PG, higher PG variability, and rain events. CTs with thinner 850–500 hPa layer are associated with higher daily mean values of fair-weather PG. We also examine the influence of CT on the frequency and amplitude of the naturally occurring extremely low-frequency electric field fluctuations known as Schumann resonances (SR) using data from a station in Hungary. The first and second mode SR frequencies are increased during CTs associated with higher 500 hPa geopotential heights and higher 850–500 hPa layer thickness. This hints to a lower-upper atmosphere coupling. So, CTs not only influence the general temperature and humidity conditions to which the biosphere is exposed, but they also affect its exposure to atmospheric electric fields. [ABSTRACT FROM AUTHOR]

This program has been initiated to study the atmospheric and meteorological parameters at a high altitude sub Himalayan location (Shillong25.58°N, 91.89°E), Shillong, Meghalaya to understand their interaction and bearing on the local climate. Design and fabrication of the integrated instrumentation for measurement and recording of atmospheric electric potential gradient, point discharge current, solar irradiance and meteorological parameters was implemented. The results obtained indicate satisfactorily the performance of the instrument in fair-weather and disturbed weather conditions. [ABSTRACT FROM AUTHOR]

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The Global atmospheric Electric Circuit (GEC) sustains the fair weather (FW) electric field, or potential gradient (PG). In this article, we analyze PG measurements recorded between 2017 and 2021 at the Instituto de Investigaciones Científicas y Técnicas para la Defensa (CITEDEF) in Buenos Aires, Argentina, to calculate the daily PG (FW) curve and examine whether local PG measurements capture the GEC signal. With the aim of supporting future common methodologies that do not rely on meteorological data for FW identification - and hence aid inter-comparisons, we rely on previously developed statistical methodologies to propose a FW selection based on the absolute deviation from the median of the data series. Using this methodology we filtered FW days and showed that the local PG (FW) curve had a significant correlation of 0.83 with the Carnegie curve. In order to test the extent to which the local daily PG (FW) curve captures the global thunderstorm signal, the area of thunderstorms was calculated at both global and regional scales using data from the Thunder Hour Database (http://thunderhours.earthnetworks.com). The PG (FW) curve was shown to have a good correlation with the daily median variation of the global thunderstorm area on both annual and quarterly scales. Additionally, the analysis of coincident aerosol optical thickness (AOD) measurements by the AERONET network and temperature observations helped to conclude that local effects such as pollution from a near highway are not dominating the PG (FW) curve behaviour. Both analyses allowed us to conclude that the GEC signal can be detected in Buenos Aires. [Display omitted] • The daily PG curve (FW) in Buenos Aires has a correlation of 0.83 with the Carnegie curve with 95% confidence. • The daily PG (FW) curve in Buenos Aires has a seasonal variation that accompanies the global changes of thunderstorm areas. • Local effects such as pollution from a near highway are not dominating the PG (FW) curve behaviour. [ABSTRACT FROM AUTHOR]

The possibility of rainfall nowcasting using a new parameter — atmospheric electric field (potential gradient, PG) — is investigated. The temporal behavior of the PG measured by a ground-based electric field mill before rainfall was analyzed at the University of Reading Atmospheric Observatory (51.441°N, 0.938°W, 66 m) in 2007–2021 and the Nor Amberd research station (40.367°N, 45.258°E, 2000 m) in 2013–2018. The PG tend to show abnormal oscillations before the precipitation cloud arrived at the PG measuring site. Several rules were applied to determine rainfall and PG oscillation events. Statistical analysis was conducted, and the results showed that PG oscillations occurred before and overlap with 48% (54%) of rainfall events, and PG oscillations occurred in one hour before 68% (77%) of rainfall events started at the University of Reading Atmospheric Observatory site (Nor Amberd research station site). A PG-based rainfall nowcasting model is proposed, which is constructed using machine learning techniques Fully Connected Neural Network and Tree-based Pipeline Optimization Tool. The hit rate, false alarm rate, missed detection rate, TS score of the model reached 93.8% (94.6%), 36% (37.4%), 37.7% (39.3%), 46.1% (44.5%) respectively, which is comparable to that of the state-of-the-art rainfall nowcasting methods. And the heavy rainfall hit rate reached 41.5% (36.4%). PG show a great potential to be used as a new parameter for rainfall nowcasting. And the effect of rainfall nowcasting method that proposed in this paper is barely affected by the weather conditions and the PG measuring range of different sites. Moreover, PG stands out among many other parameters because long-term and stable PG measurements can be obtained at a very low cost using an electric field mill. • The possibility of rainfall nowcasting using a new parameter — atmospheric electric field (potential gradient, PG) — is investigated. • The results of statistical analysis showed that PG oscillations occur in one hour before 68% (77%) of rainfall events start at the University of Reading Atmospheric Observatory (Nor Amberd research station) site. • Model that using PG to nowcast rainfall achieved 93.8% (94.6%) hit rate, 36% (37.4%) false alarm rate, 37.7% (39.3%) missed detection rate. And the heavy rainfall hit rate reached 41.5% (36.4%). The performance of the model is barely affected by the weather conditions and the PG measuring range of different sites. [ABSTRACT FROM AUTHOR]

The El Niño-Southern Oscillation (ENSO) modifies precipitation patterns across the planet. Charge separation in disturbed weather and thunderstorms drives the global atmospheric electric circuit (GEC), hence ENSO-induced precipitation changes are anticipated to affect the global circuit. By analysing historical atmospheric electricity data using a new data processing procedure based on the Carnegie curve, signals correlated with ENSO sea surface temperature (SST) anomalies are revealed. These demonstrate a persistent ENSO-GEC relationship for the majority of the twentieth century, in potential gradient data from Lerwick, Shetland and Watheroo, W. Australia. The recovered data is weighted towards the first half of the UTC day, giving a GEC sensitivity up to ∼5% °C ^−1 of SST anomaly in the Niño 3.4 and 4 regions of the Pacific Ocean. Transferring ENSO variability by electrical means represents an unexplored teleconnection, for example, through proposed GEC effects on stratiform cloud microphysics. The strong ENSO-GEC relationship also provides a quality test for historical atmospheric electricity data, and encourages their use in reducing SST reconstruction uncertainties.

The purpose of the present study is to investigate the impact of rain, snow and hail on potential gradient (PG), as observed in a period of ten years in Xanthi, northern Greece. An anticorrelation between PG and rainfall was observed for rain events that lasted several hours. When the precipitation rate was up to 2 mm/h, the decrease in PG was between 200 and 1300 V/m, in most cases being around 500 V/m. An event with rainfall rates up to 11 mm/h produced the largest drop in PG, of 2 kV/m. Shortly after rain, PG appeared to bounce back to somewhat higher values than the ones of fair-weather conditions. A decrease in mean hourly PG was observed, which was around 2–4 kV/m during the hail events which occurred concurrently with rain and from 0 to 3.5 kV/m for hail events with no rain. In the case of no drop, no concurrent drop in temperature was observed, while, for the other cases, it appeared that, for each degree drop in temperature, the drop in hourly mean PG was 1000 V/m; hence, we assume that the intensity of the hail event regulates the drop in PG. The frequency distribution of 1-minute PG exhibits a complex structure during hail events and extend from −18 to 11 kV/m, with most of the values in the negative range. During snow events, 1-minute PG exhibited rapid fluctuations between high positive and high negative values, its frequency distribution extending from −10 to 18 kV/m, with peaks at −10 and 3 kV/m.

Schematic illustration of interface separation of the Kovar alloy–borosilicate glass anodically bonded joint by application of opposite polarity voltage. The red arrows represent the thermal stress caused by the bond interface. • Interface separation of anodically bonded joints is clarified. • Bond interface of bonded joint separated by opposite polarity voltage application. • Brittle Na–Si oxide layer formed by opposite polarity application. • Lower bonding temperature increased rate of interface separation. • Higher temperature during voltage application increased separation rate. Anodic bonding is a process for bonding metal to ion-conductive glass at a temperature lower than the glass softening point, where a DC voltage is applied to the metal and glass with an anode and a cathode, respectively. In this study, when opposite polarity voltage was applied to anodically bonded Kovar alloy–borosilicate glass joints, the bond interface separated. Because Na accumulated at the bond interface by application of opposite polarity voltage, a brittle Na and Si compound oxide layer removed from the vitrification region formed adjacent to the bond interface. It is considered that destruction of the brittle oxide layer is caused by the thermal stress owing to a slight difference in the linear expansion coefficient and the elastic stress caused by bonding between bond surfaces with imperfect flatness, resulting in separation of the bond interface. The interface separation speed decreased with higher bonding temperature and lower temperature during application of opposite polarity voltage. Because movement of alkali ions becomes easy when the bonding temperature is high, the width of the alkali ion depletion layer formed adjacent to the bond interface was large in joints with high bonding temperature. When opposite polarity voltage was applied, the potential gradient of the alkali depletion layer became large and the potential gradient of the glass bulk became gradual. As a result, movement of Na ions toward the bonding interface was suppressed and it took a long time to reach the Na concentration required to separate the interface. [ABSTRACT FROM AUTHOR]

Every ecological group of plants including hygrophytes, mesophytes and xerophytes is characterized by a definite narrow interval of the soil water potential, in which the values of relative transpiration cannot be lower than the optimal level (1.0-0.9). These intervals take into account the influence of soil properties (moisture potential) and meteorological conditions (transpiration) and can be used as optimal indices for the water supply of plants. The peculiar soil water uptake by plants has been studied to show that the soil water and its intensive uptake become increasing but its “dead” reserve decreasing from hygrophytes towards mesophytes and then xerophytes. It is worth emphasizing that the decline in the growth and accumulation of useful products by plants occur due to decreasing the content of soil water to the lower boundary of optimal moistening. The further decrease in soil moisture leads to permanent and then ultimate wilting of plants. Under study were also intervals for soil water potential corresponding to the moisture of ultimate wilting of different ecological plant groups. Lettuce (hygrophyte) is becoming dead when the content of soil water is equal to 1.5, oat (mezophyte) - 1.0 and xerophytes - lower than 1.0 of the wilting moisture. The method of “vegetative miniatures” widely adopted now is imperfect and can be performed only for preliminary notions about the lower limit for plant availability of the soil water.

Highlights • A 3-year record of atmospheric electric potential gradient (PG) for Muzaffarabad. • Preliminary results show a distinct double oscillation and deviates from the oceanic Carnegie curve. • Seasonal PG values are higher in winter and spring as compared to summer and autumn seasons. • Aerosol concentration plays an imperative role in atmospheric electricity. Abstract The atmospheric electric Potential Gradient (PG) variation of fair-weather days at Muzaffarabad (MZF, Northern Pakistan) station is presented for the period of January 2015–October 2017. The present investigations focus on the diurnal variation of atmospheric PG on the seasonal and annual time scale. The fair-weather seasonal and annual average PG variation has revealed two peaks, i.e. a primary maximum peak and a secondary maximum peak. The average maximum PG value found is ∼410 Vm−1. The results are then compared with the well-known standard oceanic Carnegie curve. The diurnal curve of PG is found to deviate from the Carnegie curve. The seasonal PG variation at MZF shows lower values during the summer (monsoon) and autumn (post-monsoon) as compared to the winter and spring (pre-monsoon) which could be due to local aerosol concentration. Global comparison of PG (%) values of the annual mean at different longitude, with MZF observatory, shows local morning and evening peaks depicting local sunrise and sunset effects on the PG. The overall outcomes will certainly contribute to further investigate the Global Electric Circuit (GEC). [ABSTRACT FROM AUTHOR]