Estimation of nighttime ionospheric D-region parameters using tweek atmospherics observed for the first time in the North African region

Ammar, Ahmed Ben; Ghalila, Hassen

doi:10.1016/j.asr.2020.08.025

Cited by 10 publications

(7 citation statements)

References 19 publications

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“…Quantifying the effects of lightning on the Earth system, and understanding where and how lightning presents hazards, requires an estimate of the timing, geographical distribution, and intensity of lightning strokes at continental to global scales. Large-scale maps of lightning occurrence are as important as those for temperature or precipitation in some land surface (Hantson et al, 2016) and atmospheric chemistry models (Finney et al, 2016), and are valuable in their own right for understanding various meteorological phenomena such as the frequency and distribution of extreme precipitation (e.g., Williams, 2005) and for risk and hazard assessment (e.g., Ashley and Gilson, 2009;Koshak et al, 2015). Observing and mapping lightning distribution at large spatial scales has thus been a priority for the community for nearly a century (Brooks, 1925;Komarek, 1964).…”

Section: Introductionmentioning

confidence: 99%

The WGLC global gridded lightning climatology and time series

Kaplan

Lau

2021

Earth Syst. Sci. Data

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Abstract. Lightning is an important atmospheric phenomenon and has wide-ranging influence on the Earth system, but few long-term observational datasets of lightning occurrence and distribution are currently freely available. Here, we analyze global lightning activity over the second decade of the 21st century using a new global, high-resolution gridded time series and climatology of lightning stroke density based on raw data from the World Wide Lightning Location Network (WWLLN). While the total number of strokes detected increases from 2010–2014, an adjustment for detection efficiency reduces this artificial trend. The global distribution of lightning shows the well-known pattern of greatest density over the three tropical terrestrial regions of the Americas, Africa, and the Maritime Continent, but we also noticed substantial temporal variability over the 11 years of record, with more lightning in the tropics from 2012–2015 and increasing lightning in the midlatitudes of the Northern Hemisphere from 2016–2020. Although the total number of strokes detected globally was constant, mean stroke power decreases significantly from a peak in 2013 to the lowest levels on record in 2020. Evaluation with independent observational networks shows that while the WWLLN does not capture peak seasonal lightning densities, it does represent the majority of powerful lightning strokes. The resulting gridded lightning dataset (Kaplan and Lau, 2021a, https://doi.org/10.5281/zenodo.4774528) is freely available and will be useful for a range of studies in climate, Earth system, and natural hazards research, including direct use as input data to models and as evaluation data for independent simulations of lightning occurrence.

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Section: Introductionmentioning

confidence: 99%

The WGLC global gridded lightning climatology and time series

Kaplan

Lau

2021

Earth Syst. Sci. Data

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“…which is used in numerous previous papers [56][57][58][59]. Here, N e , β, and H and the considered D-region altitude h are given in m −3 , km −1 and km, respectively; •…”

Section: Determination Of Vtec Dmentioning

confidence: 99%

The Influence of Solar X-ray Flares on SAR Meteorology: The Determination of the Wet Component of the Tropospheric Phase Delay and Precipitable Water Vapor

et al. 2021

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In this work, we study the impact of high-energy radiation induced by solar X-ray flares on the determination of the temporal change in precipitable water vapor (ΔPWV) as estimated using the synthetic aperture radar (SAR) meteorology technique. As recent research shows, this radiation can significantly affect the ionospheric D-region and induces errors in the estimation of the total electron content (TEC) by the applied models. Consequently, these errors are reflected in the determination of the phase delay and in many different types of measurements and models, including calculations of meteorological parameters based on SAR observations. The goal of this study is to quantify the impact of solar X-ray flares on the estimation of ΔPWV and provide an estimate of errors induced if the vertical total electron content (VTEC) is obtained by single layer models (SLM) or multiple layer models (MLM) (these models do not include ionosphere properties below the altitude of 90 km as input parameters and cannot provide information about local disturbances in the D-region). The performed analysis is based on a known procedure for the determination of the D-region electron density (and, consequently, the vertical total electron content in the D-region (VTECD)) using ionospheric observations of very low frequency (VLF) radio waves. The main result indicates that if the D-region, perturbed by medium-sized and intense X-ray flares, is not modeled, errors occur in the determination of ΔPWV. This study emphasizes the need for improved MLMs for the estimation of the TEC, including observational data at D-region altitudes during medium-sized and intense X-ray flare events.

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“…Lightning discharges generate broadband electromagnetic radiation, mainly in the frequency band from 1 Hz to 300 MHz (Gu et al, 2022), among them, electromagnetic pulses in the very-low-frequency (VLF; 3-30 kHz) band are widely used in long-range lightning location. Such signals are also called sferics, which can propagate thousands of kilometers in the Earth-ionosphere waveguide (EIWG) with little attenuation (~2-3 dB/ OPEN ACCESS EDITED BY 1,000 km) (Ammar and Ghalila, 2020). The LLSs mainly use the time of arrival (TOA) method and the time difference of arrival (TDOA) method, which uses the time difference between the LEMP signal and the station to location, so LLSs can obtain high lightning location accuracy, and the average error is generally on the order of hundred meters (Zhang et al, 2010;Shi et al, 2017;Wang et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

Evaluation and revision of long-range single-site lightning location accuracy considering the time delay of ground wave

Zhou

Zhang

et al. 2023

Front. Environ. Sci.

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Detecting the distance and orientation of long-distance thunderstorms has very important practical significance. The multi-station lightning location system relies on a high-precision time module and good network communication capabilities, but in some cases these conditions cannot be met, but there is still a need for lightning activity monitoring, and it is very important to establish a single-site lightning location system. In this paper, we have established a long-distance single-site lightning location station, and in order to improve the accuracy of distance estimation, a numerical algorithm is used to obtain the relationship between the ground wave arrival time delay and the propagation distance, and it is used to revise the time difference between the peak value of the skywave and ground wave. Moreover, we used multi-station lightning location data to revise the site-error in magnetic direction finder method to improve the accuracy of the direction calculation. The results show that the effective detection range of the single-site we have been established is 200 km–2000 km, and the revised average direction deviation dropped from 12.3° to 8.6°. The verification results of thunderstorms within the effective detection range show that the relative error of single-site lightning location is 8.4%–18.6% after the revision.

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Estimation of nighttime ionospheric D-region parameters using tweek atmospherics observed for the first time in the North African region

Cited by 10 publications

References 19 publications

The WGLC global gridded lightning climatology and time series

The WGLC global gridded lightning climatology and time series

The Influence of Solar X-ray Flares on SAR Meteorology: The Determination of the Wet Component of the Tropospheric Phase Delay and Precipitable Water Vapor

Evaluation and revision of long-range single-site lightning location accuracy considering the time delay of ground wave

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