Fair-weather Atmospheric Electric Field Research Articles

A simple time-domain “2D” median filter for atmospheric electric field denoising

In this paper, we propose a new simple method for obtaining fair-weather Atmospheric Electric Field (Potential Gradient, PG) data based on PG only. We design a filter called “two-dimension” (”2D”) median filter to reduce disturbed-weather PG noises rather than choosing fair-weather PG using conventional approaches. “2D” means that when filtering PG data, the filter considers PG from days that are close to the PG measurement time in addition to PG near the PG measuring time, as is the case with a standard one-dimension median filter. The open access GloCAEM dataset is used to assess this filter's efficacy. The results show that comparing to other simple filters, it has significant effect on reducing disturbed-weather PG noises, at the same time, has little effect on the fair-weather PG signals. Moreover, compared to conventional fair-weather PG selecting methods, PG after being filtered is very similar to fair-weather PG while do not have extra missing values in the PG. “2D” median filter can be an alternative method for obtaining mean diurnal variation of fair-weather PG. The PG after being filtered can also be used for researching other fair-weather related phenomena directly.

Comparison of the Atmospheric Electric Field from Three Global Stations in 2021

The atmospheric electric field is an important physical parameter used to study the state of charge density distribution between the earth and the ionosphere, and its daily variation characteristics reflect the underlying atmospheric electrical properties in a region. In this paper, we used atmospheric electric field data from three global observation stations (the Xanthi station, the Zhuanghe station, and the University of Reading station) from January to December 2021 and then combined these data with meteorological data and geomagnetic activity data to filter the fair-day atmospheric electric field data and plot the average fair-weather atmospheric electric field curve. Then, we compared different sunrise and sunset times and PM 2.5 concentrations, analyzed the seasonal differences for each station, the differences among the three stations, and the difference between their curves and the Carnegie curve, and finally concluded that the difference among them showed positive correlations with PM 2.5 concentrations. The other possible reasons and the entire shape of the average fair-weather atmospheric electric field curve for a defined station are not affected by the season, including the location of peaks and valleys, and the overall variation have been also revealed.

Diurnal variation of the fair-weather atmospheric electric field in Binchuan, China

With the purpose of understanding the variation of fair-weather atmospheric electric field, the vertical component of atmospheric electric field (recorded as Ez) has been measured in the town Binchuan (25°50′N, 100°34′E, 1438.7 m asl) of Dali city, Yunnan, China from June 14, 2017 to December 1, 2020. Automatic measured visual range is used as a proxy of aerosol concentration. The mean diurnal variation curve of the fair-weather Ez in Binchuan, having two peaks occurred at around 9LT and 20LT, shows little correlation with the well-known Carnegie Curve and other two high-latitude sites' Curves. While strong negative correlation between fair-weather Ez and visual range is found, indicating the variation of fair-weather is dominated by aerosol concentration. The main source of aerosol concentration variation probably sunrise and sunset effect. We support our findings by comparing Ez, visual range with sunrise and sunset times. The peaks (troughs) of Ez (visual range) are proved to have weak correlations with anthropogenic pollution through comparing the Ez, visual range under workdays and holidays.

Fair-Weather Near-Surface Atmospheric Electric Field Measurements at the Zhongshan Chinese Station in Antarctica

The variability in the atmospheric electric field is modulated by a combination of solar activities, meteorological activities, and geological conditions. A foundational dataset of the daily variations in the fair-weather atmospheric electric field is established in this study, and several examinations are conducted into the details of these variations in particular regions. This paper is organized as follows. First, the researchers count the datasets of daily variations to the atmospheric electric field on fair-weather days from 1 March–1 August 2022 at Zhongshan Chinese Station in Antarctica and Changping Station in Beijing. Then, the average daily variation in the atmospheric electric field on 40 fair-weather days in Antarctica is shown and the variations are compared with the average curve of 37 fair-weather days in Beijing during the same time period. Finally, the three main differences between these variations, their possible reasons, and a reasonable error analysis are clarified and discussed at the end of this paper.

Characteristics of Fair-weather Atmospheric Electric Field in Tibetan Ngari Prefecture

晴天大气电场是一个区域大气电场变化的基准场，是大气电场特性的研究基础。对于具有不同地质条件、地理环境和地形特点的区域，晴天大气电场特征具有明显区别。利用在西藏阿里地震台（80.12°E，32.51°N）安装的一台场磨式大气电场仪于2021年10月10日至2021年11月10日观测到的数据，通过对大气电场数据建模与分析，结合气象条件，得到西藏阿里地区23天晴天条件下的平均卡耐基曲线。经过平滑处理去除仪器噪声的波动，得到西藏阿里地区的晴天条件下的标准卡耐基曲线，进而与北京市昌平区十三陵观测台站（116.23°E，40.25°N）同期的晴天大气电场特征进行对比，并对其电场特性差异和原因进行了讨论。研究结果对分析高原地区晴天大气电场特征具有重要的参考价值和科学意义。

Local Impacts Dominate the Diurnal Variation of the Fair-Weather Atmospheric Electric Field in Yunnan, China

Local Impacts Dominate the Diurnal Variation of the Fair-Weather Atmospheric Electric Field in Yunnan, China

Fair-weather atmospheric electric field measurements at Gulmarg, India

Fair-weather atmospheric electric field measurements at Gulmarg, India

Study of fair weather surface atmospheric electric field at high altitude station in Eastern Himalayas

Abstract Fair weather atmospheric electric field has been studied at Darjeeling (latitude 27001′N longitude 88036′E, 2200 masl), a high altitude station in eastern Himalayas and compared with the Carnegie curve. The potential gradient (PG) measured is larger than Carnegie curve for most of the time of the day. In order to understand the effect of the local components we have studied the PG variation along with the meteorological parameters and atmospheric constituents such as mixed layer depth, potential temperature, PM2.5, black carbon (BC), aerosol optical depth (AOD), integrated water vapour and liquid water. The local components like PM2.5 and BC show a good correlation with PG. On the other hand Columnar quantities like AOD as well as integrated water vapour and liquid water shows negative correlation with PG which could be associated with the higher mobile negative charges and the complex behavior of space charges. The periodogram of fair weather PG data shows one half day, one day and 100 days periodicity, the power being maximum for one day period. A comparison with other observations shows the presence of larger number of peaks in summer. Morning and evening PG are in general lower compared to the other sites.

Experimental Study of Diurnal and Seasonal Variations in the Atmospheric Electric Field

In order to separate global and local effects of atmospheric electricity, measurements of the fair-weather electric field were performed in Nizhny Novgorod in 2013-2018. As a result of processing 139 diurnal records from four observation points spaced 6–8 km apart, diurnal variations in the fair-weather atmospheric electric field for different seasons and weekdays (working days and weekends) were studied. The curve of the local diurnal variation is shown to always have two maxima. The evening maximum of the diurnal variation (19:00–20:00 UT) coincides in time with the maximum of the Carnegie curve, which is a characteristic of the global electrical circuit. The highest values of the field amplitude are reached in the winter period. The field-intensity maximum in the first half of the day (09:00–11:00 LT) is characteristic of the urban environment and shows that local effects associated with the presence of aerosol particles in the air significantly contribute to the formation of diurnal variation, especially in summer. According to the 2013–2018 measurements, the seasonal variation in the monthly-average values of the atmospheric electric field is revealed and analyzed compared with the results of measurements of seasonal variation in other regions of the globe. The obtained results allow one to reveal the role of local effects in the formation of diurnal variation in the mid-latitude areas with temperate continental climate and provide a basis for developing a theory which can explain the physical mechanisms of local effects and suggest appropriate parametrization for finding the surface electric field in the weather and climate models.

A Preliminary Study of Fair-Weather Atmospheric Electric Field at a High Altitude Station (Shillong) 25° N, 91° E.

A Preliminary Study of Fair-Weather Atmospheric Electric Field at a High Altitude Station (Shillong) 25° N, 91° E.

Preliminary results of fair-weather atmospheric electric field in the proximity of Main Boundary Thrust, Northern Pakistan

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).

On the Negatively Charged Layer of the Earth’s Electric Field

Based on the hydridic Earth model, we propose a hydridic model of the Earth’s electric field. The model predicts that the negative electrode of the Earth’s capacitor is located under the Earth’s crust and the Earth’s fluids carry a positive charge. We have observed an excess of positive charge in the Earth’s crust down to kilometer depths. The model explains the unitary variation of the fair-weather atmospheric electric field strength, the change in atmospheric electric field strength and the precipitation of high-energy electrons during earthquakes.

A preliminary study on time series forecast of fair-weather atmospheric electric field with WT-LSSVM method

Accurate forecasting of fair-weather atmospheric electric field is of great importance to denote the climate change, and it also plays a vital role in lightning forecasting. In this paper, the WT (Wavelet transform)-LSSVM (Least squares support vector machine) method is proposed to develop a model to forecast time series of fair-weather atmospheric electric field. The application experiments with data from Verhnee Dubrovo, Dusheti, and Voeikovo stations show that the predicted data and observed value have the same tendency. The correlation coefficients between them are 0.8149, 0.6395 and 0.7308, while the MSE are 16.9869 V/m, 28.8876 V/m and 32.2163 V/m, respectively. Furthermore, comparing to LSSVM and ANN, WT-LSSVM is a superior method to predict the monthly mean values of fair-weather atmospheric electric field. • A new method is proposed to forecast of fair-weather atmospheric electric field. • The model is a running-extrapolation model based on WT -LSSVM method. • Comparing with LSSVM and ANN, WT-LSSVM method is better for prediction.

Observation of the variations of the atmospheric electric field at YBJ, Tibet

The variability noticed in fair weather atmospheric electric field (AEF) recorded at Yangbajin (YBJ, 90°31′50″E, 30°06′38″N), a continental station located at Tibet Plateau, China, during the period 2006–2011, has been examined firstly in relation to the variations of three selected local meteorological parameters. Secondly, a test has been carried out for a hypothesis that numerical reduction on the variations of fair weather AEF data according to the meteorological parameters like air pressure, temperature and relative humidity, could weaken its meteorological effect and thus help to study the variations of AEF. The reduction effectively suppresses the annual variation, but the shape of the diurnal variation remains the same, and is widely different from the Carnegie Curve. Finally, the seasonal effects of diurnal variations are analyzed. The most distinctive characteristics of the fair weather AEF here is that the pattern of diurnal variations exhibits a double fluctuation, which is modulated by the sunrise and sunset effect. The phase of the diurnal curve has a little shift with seasons.

Periodic variations of atmospheric electric field on fair weather conditions at YBJ, Tibet

Observations of atmospheric electric field on fair weather conditions from the plateau station, YBJ, Tibet (90°31′50″ E, 30°06′38″ N), over the period from 2006 to 2011, are presented in this work. Its periodic modulations are analyzed in frequency-domain by Lomb-Scargle Periodogram method and in time-domain by folding method. The results show that the fair weather atmospheric electric field intensity is modulated weakly by annual cycle, solar diurnal cycle and its several harmonic components. The modulating amplitude of annual cycle is bigger than that of solar diurnal cycle. The annual minimum/maximum nearly coincides with spring/autumn equinox. The detailed spectrum analysis show that the secondary peaks (i.e. sidereal diurnal cycle and semi-sidereal diurnal cycle) nearly disappear along with their primary peaks when the primary signals are subtracted from electric field data sequence. The average daily variation curve exhibits dual-fluctuations, and has obviously seasonal dependence. The mean value is bigger in summer and autumn, but smaller in spring and winter. The daytime fluctuation is affected by the sunrise and sunset effect, the occurring time of which have a little shift with seasons. However, the nightly one has a great dependence on season conditions.

The Carnegie Curve

Abstract The Earth’s fair weather atmospheric electric field shows, in clean air, an average daily variation which follows universal time, globally independent of the measurement position. This single diurnal cycle variation (maximum around 19UT and minimum around 03UT) is widely known as the Carnegie curve, after the geophysical survey vessel of the Carnegie Institution of Washington on which the original measurement campaigns demonstrating the universal time variation were undertaken. The Carnegie curve’s enduring importance is in providing a reference variation against which atmospheric electricity measurements are still compared; it is believed to originate from regular daily variations in atmospheric electrification associated with the different global disturbed weather regions. Details of the instrumentation, measurement principles and data obtained on the Carnegie’s seventh and final cruise are reviewed here, also deriving new harmonic coefficients allowing calculation of the Carnegie curve for different seasons. The additional harmonic analysis now identifies changes in the phasing of the maximum and minimum in the Carnegie curve, which shows a systematic seasonal variation, linked to the solstices and equinoxes, respectively.

The study of meteorological effects and time variations of the fair weather atmospheric electric field near ground in YBJ, Tibet

Based on the fair weather atmospheric electric field recorded by YBJ Cosmic Ray Station located at the YBJ High Altitude Cosmic Ray Laboratory (90° 31'50" E, 30° 06'38" N, 4300 m a.s.l., 606 g/cm2), Tibet, China, its meteorological effects and time variations are studied. The analysis in this paper is to look into how the factors like atmospheric pressure, temperature and relative humidity in the presence of the meteorological factors in four seasons govern the fair weather atmospheric electric field at the site of measurement. The results of meteorological effects show that there is a strong positive correlation between the fair weather atmospheric electric field and temperature, while a moderate positive correlation is seen between the fair weather atmospheric electric field and the atmospheric pressure, also the relative humidity. The long-term variations of the fair weather atmospheric electric field are affected by seasons. The mean value is higher in summer and fall, but lower in winter and spring. The daily variation of the fair weather atmospheric electric field is modulated by solar diurnal, semi-solar diurnal, and its third and fourth harmonic component. The higher the harmonic frequency, the lower the modulate amplitude is. The daily variation curves show bimodal variation with evening peak and sunrise peak. Two minima can also be seen in early morning and evening. Sunrise peak value is highest during summer and fall, but lowest in spring and winter morning. Sunrise peak occurs at around noon, and evening peak is modulated by the season effects.

Influences of cosmic radiation, artificial radioactivity and aerosol concentration upon the fair-weather atmospheric electric field in Lisbon (1955–1991)

The atmospheric electric field is influenced by cosmic radiation, radioactivity and aerosols. In this work we investigate the existence of: (i) correlations between relative anomalies of annual values of atmospheric electric field and cosmic radiation intensity, artificial radioactivity and aerosol concentration; (ii) seasonal correlations between relative anomalies of the atmospheric electric field and cosmic radiation intensity. We used data of the electric field strength recorded at the Portela meteorological station (Lisbon) in the period 1955–1991. We found statistically significant inverse correlations between atmospheric electric field and cosmic radiation in the period 1967–1991. We also found that the influence of cosmic radiation on the atmospheric electric field is strong in wintertime and very weak in summertime. The GCR–CN–CCN–Cloud Hypothesis and the wintertime reduced boundary layer convection are analyzed as possible explanations for this difference.

Solar Wind Control of the Earth's Electric Field

The sun-weather problem is placed within an electrical framework subject to experimental investigation. An explanation is suggested for how solar variability modulates the earth's electric field. The solar wind velocity is inversely correlated with the electrical potential of the ionosphere, a measure of the overall intensity of the earth's fair-weather atmospheric electric field. In seeking a physical cause of this relationship, galactic cosmic radiation was studied and it was also found to be inversely correlated with solar wind velocity. Thus, the earth's electric field intensity which is maintained by worldwide thunderstorm currents-a meteorological phenomenon-varies in phase with cosmic radiation. Since cosmic radiation is the primary source of atmospheric ionization, these findings support a proposed mechanism in which solar control of ionizing radiation modulates atmospheric electrification and thus possibly cloud physical processes. If the latter occurred, atmospheric energetics would be affected. Sun-weather research need no longer only consist of statistical correlations; an experimental approach is described. Establishment of a proposed geoelectric index would add a new dimension to solar-terrestrial studies.