Status of GGOS JWG3 on Improved understanding of space weather events and their monitoring

2021 ◽  
Author(s):  
Alberto Garcia-Rigo ◽  
Benedikt Soja ◽  
Keyword(s):  
Space Weather ◽  
Real Data ◽  
Weather Conditions ◽  
Electron Content ◽  
Solar Radio Flux ◽  
Direct Observations ◽  
Multiple Datasets ◽  
Weather Events ◽  
Earth Environment ◽  
Space Geodetic Techniques

<p>The JWG3 aims at investigating different approaches to monitor space weather events using the data from different space geodetic techniques and, in particular, combinations thereof. Simulations will also be considered since these could be beneficial to identify the contribution of different techniques and prepare for the analysis of real data. Different strategies for the combination of data are also to be investigated, in particular the weighting of estimates from different techniques in order to increase the performance and reliability of the combined estimates.</p><p>Furthermore, existing algorithms for the detection and prediction of space weather events shall be explored and improved to the extent possible. Additionally, the geodetic measurement of the ionospheric electron density will be complemented by direct observations from the Sun gathered from existing spacecraft, such as SOHO, ACE, SDO, Parker Solar Probe, among others. The combination and joint evaluation of multiple datasets from different space geodetic observation techniques (e.g., geodetic VLBI) is still a great challenge. In addition, other indications for solar activity - such as the F10.7 index on solar radio flux, SOLERA as EUV proxy or rate of Global Electron Content (dGEC), provide additional opportunities for comparisons and validation.</p><p>As per JWG3 objectives, these include the identification of the key parameters useful to improve real time/prediction of ionospheric/plasmaspheric VTEC, Ne estimates, as well as ionospheric perturbations, in case of extreme solar weather conditions. In general, we are on the way to gain a better understanding of space weather events and their effect on Earth’s atmosphere and near-Earth environment.</p>

scholarly journals New GGOS JWG3 on Improved understanding of space weather events and their monitoring

2020 ◽  
Author(s):  
Alberto Garcia-Rigo ◽  
Benedikt Soja
Keyword(s):  
Electron Density ◽  
Space Weather ◽  
International Association ◽  
Real Data ◽  
Weather Conditions ◽  
Electron Content ◽  
Vertical Total Electron Content ◽  
Total Electron ◽  
Weather Events ◽  
Space Geodetic Techniques

<p>Multiple space geodetic techniques are capable of measuring effects caused by space weather events. In particular, space weather events can cause ionospheric disturbances correlated with variations in the vertical total electron content (VTEC) or the electron density (Ne) of the ionosphere.</p><p>In this regard and in the context of the new Focus Area on Geodetic Space Weather Research within IAG’s GGOS (International Association of Geodesy; Global Geodetic Observing System), the Joint Working Group 3 on Improved understanding of space weather events and their monitoring by satellite missions has been created as part of IAG Commission 4, Sub-Commission 4.3 to run for the next four years.</p><p>Within JWG3, we expect investigating different approaches to monitor space weather events using the data from different space geodetic techniques and, in particular, combinations thereof. Simulations will be beneficial to identify the contribution of different techniques and prepare for the analysis of real data. Different strategies for the combination of data will also be investigated, in particular, the weighting of estimates from different techniques in order to increase the performance and reliability of the combined estimates. Furthermore, existing algorithms for the detection and prediction of space weather events will be explored and improved to the extent possible. Furthermore, the geodetic measurement of the ionospheric electron density will be complemented by direct observations from the Sun gathered from existing spacecraft, such as SOHO, ACE, SDO, Parker Solar Probe, among others. The combination and joint evaluation of multiple datasets with the measurements of space geodetic observation techniques (e.g. geodetic VLBI) is still a great challenge. In addition, other indications for solar activity - such as the F10.7 index on solar radio flux, SOLERA as EUV proxy or rate of Global Electron Content (dGEC)-, provide additional opportunities for comparisons and validation.</p><p>Through these investigations, we will identify the key parameters useful to improve real-time/prediction of ionospheric/plasmaspheric VTEC, Ne estimates, as well as ionospheric perturbations, in case of extreme solar weather conditions. In general, we will gain a better understanding of space weather events and their effect on Earth’s atmosphere and near-Earth environment.</p>

Statistical Analysis of Extreme Electron Fluxes in the Radiation Belts

2017 ◽  
Vol 13 (S335) ◽  
pp. 128-131
Author(s):  
Vanina Lanabere ◽  
Sergio Dasso
Keyword(s):  
Distribution Function ◽  
Space Weather ◽  
Radiation Belt ◽  
Weather Conditions ◽  
Value Theory ◽  
Cumulative Distribution ◽  
Outer Radiation Belt ◽  
Weather Events ◽  
Polar Satellite ◽  
Energy Channels

AbstractThe main aim of this work is to study the frequency of extreme Space Weather events, in particular to analyse the tails of the daily averaged electron fluxes distribution function for different channels of energy between 0.249–1.192 MeV measured at ~ 600 km of altitude with the particle detector ICARE-NG/CARMEN-1 on board argentinian polar satellite SAC-D. An extreme value theory was applied to estimate the maximum values of the electron flux in the outer radiation belt for different return levels. We found that the cumulative distribution function of the extreme electron fluxes presents a finite upper limit in (1) the core of the outer radiation belt for the lower energy channels and (2) in the inner edge of the outer radiation belt for energy channels larger than 0.653 keV. The results presented in this work are important to characterise Space Weather conditions.

scholarly journals Ionospheric Response to the Space Weather Events of 4-10 September 2017: First Chilean Observations

2019 ◽  
Vol 13 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Manuel Bravo ◽  
Carlos Villalobos ◽  
Rodrigo Leiva ◽  
Luis Tamblay ◽  
Pedro Vega-Jorquera ◽  
...  
Keyword(s):  
Total Electron Content ◽  
Space Weather ◽  
Global Navigation Satellite Systems ◽  
Time Interval ◽  
Electron Content ◽  
Dual Frequency ◽  
Field Station ◽  
Total Electron ◽  
Satellite Systems ◽  
Weather Events

Objective: The diurnal variations of several ionospheric characteristics during the Space Weather Events of 4-10 September 2017, for Chilean latitudes, will be reported. Materials and Methods: Observations were made using a recently installed ionosonde at the Universidad de La Serena field station (29°52'S; 71°15’W). Also, reported is the total electron content determined using the upgraded Chilean network of dual-frequency Global Navigation Satellite Systems (GNSS) receivers. Results: Sudden ionospheric disturbances are described in terms of the minimum reflection frequency determined from ionosonde records. An attempt to derive the extent of the effect on high frequency propagation paths in the region is made using simultaneous ionosonde observations at other locations. The geomagnetic storm ionospheric effects are discussed in detail using the observed diurnal variation of maximum electron concentration (NmF2), virtual height of the F-region (h’F/F2) and Total Electron Content (TEC). These are complemented with the time-latitude variation of TEC for the 70°W meridian. Conclusion: It is found that large increases of NmF2, h’F/F2 and TEC observed during 8 September 2017 storm are well described in terms of the evolution of the Equatorial Ionospheric Anomaly (EIA) over the same time interval. Known physical mechanisms are suggested to explain most of the observations.

scholarly journals INVESTIGATION OF THE RELATIONSHIP BETWEEN IONOSPHERIC TEC ANOMALY VARIATIONS AND FAULT TYPES BEFORE THE EARTHQUAKES

2017 ◽  
Vol IV-4/W4 ◽  
pp. 383-388 ◽  
Author(s):  
M. Ulukavak ◽  
M. Yalçınkaya
Keyword(s):  
Total Electron Content ◽  
Space Weather ◽  
Environmental Changes ◽  
Weather Conditions ◽  
Earthquake Precursor ◽  
Strike Slip ◽  
Time Of Arrival ◽  
Electron Content ◽  
Total Electron ◽  
Fault Type

Earthquakes are natural phenomena that shake the earth and cause many damage. Since the time of arrival of the earthquakes cannot be determined directly, some signs before the earthquake should be examined and interpreted by examining the environmental changes. One of the methods used for this is monitoring the ionospheric total electron content (TEC) changes in total electron content unit (TECU). GPS satellites have begun to be used as a means of monitoring ionospheric TEC anomalies before earthquakes since they began to be used as sensors around the world. In this study, three fault type (normal, thrust and strike-slip faulting) of 28 earthquakes with a magnitude greater than 7 (Mw) and the percentage changes of TEC anomalies before the earthquakes were investigated. The ionospheric TEC anomalies before the earthquake were calculated according to the 15-day running median statistical analysis method. Different solar and geomagnetic indices have been investigated to determine the active space weather conditions and quiet days before and after the earthquake. The TEC anomalies were determined during the quiet days before the earthquake by comparing the ionospheric anomalies that occurred before the earthquake after the determination of quiet days with the indices of the space weather conditions. The results show that there is a relationship between fault type and the earthquake precursor percentage changes and were determined as 47.6 % TECU for regions where normal faulting, 50.4 % TECU for regions where thrust faulting, and 44.2 % TECU for regions where strike-slip faulting occurred, respectively.

scholarly journals Solar Activity and Geomagnetic Storm Effects on GPS Ionospheric TEC over Ethiopia

1970 ◽  
Vol 11 (2) ◽  
pp. 276-300
Author(s):  
Msganaw Aragaw ◽  
Abraha Gebiregiorgis ◽  
Kassa Tsegaye
Keyword(s):  
Solar Activity ◽  
Sunspot Number ◽  
Space Weather ◽  
Seasonal Variations ◽  
Geomagnetic Storms ◽  
Addis Ababa ◽  
Electron Content ◽  
Total Electron ◽  
Solar Radio Flux ◽  
Cycle 24

Ionospheric GPS total electron content (TEC) is an important parameter to monitor for possible Space Weather impacts. The effects of solar activity on TEC at low latitude stations with geographic locations (latitude, longitude) of Addis Ababa (9.040 N, 38.770 E) and Bahir Dar (11.60 N, 37.360 E) in Ethiopia, East Africa in the year of 2015 around peak of solar cycle 24 has been carried out. The data from the two stations was used to study the diurnal, monthly and seasonal variations of TEC and its dependence with solar activity and space weather effects. These observations were investigated and further discussed with an analysis of Disturbance Storm Time (Dst) and Ap indices, solar radio flux (F10.7cm) and sunspot number during the period of 2015. During the period of low or high sunspot number, that provided GPS ionospheric TEC builds up slowly or quickly. The obtained results reveal TEC undergoes diurnal and seasonal variations, daily variation of TEC value at both stations sharply increases to its peak from 0900 -1500 UT and decreases around 1600 - 0700 UT. Seasonal variations showed that TEC maximizes during the equinoctial months and least in summer over the two stations. In all seasons the maximum value of TEC in Addis Ababa is higher. The effects of geomagnetic storms on TEC values have been found negative and positive output.  

scholarly journals Ionospheric Response along Meridian for the Certain Storm Using TEC and foF2

Universe ◽  
2021 ◽  
Vol 7 (9) ◽  
pp. 342
Author(s):  
Olga Maltseva ◽  
Artem Kharakhashyan ◽  
Tatyana Nikitenko
Keyword(s):  
Space Weather ◽  
Real Data ◽  
Slab Thickness ◽  
Electron Content ◽  
Global Models ◽  
Total Electron ◽  
Long Time ◽  
Critical Frequency Fof2 ◽  
Using Data ◽  
Two Parameters

For a long time, the equivalent ionospheric slab thickness τ has remained in the shadow of ionospheric main parameters: the maximum density, NmF2 (or the critical frequency, foF2), and the total electron content. Empirical global models have been developed for these two parameters. Recently, several global models of τ have appeared concurrently. This paper compares τ of the Neustrelitz equivalent slab thickness model (NSTM), with τ(IRI-Plas) of the IRI-Plas model, and τ(Appr) of the approximation model, constructed along the 30° E meridian using data from several ionosondes. The choice of the model of the best conformity with observational data was made, which was used to study the effects of space weather during several magnetic storms in March 2012. The effects included: (1) a transition from negative disturbances at high latitudes to positive ones at low latitudes, (2) the super-fountain effect, which had been revealed and explained in previous papers, (3) a deepening of the main ionospheric trough. The efficiency of using τ(Appr) and τ(IRI-Plas) models for studying the effects of space weather has been confirmed. The advantage of the τ(Appr) model is its closeness to real data. The advantage of the τ(IRI-Plas) model is the ability to determine foF2 without ionosondes. The efficiency of the NSTM model is insufficient for a role of a global τ model due to the accuracy decreasing with the increasing latitude.

Producing solar flare predictions using support vector machine (SVM) applied with ionospheric total electron content (TEC) global maps

2020 ◽  
Author(s):  
Saed Asaly ◽  
Lee-Ad Gottlieb ◽  
Yuval Reuveni
Keyword(s):  
Solar Flare ◽  
Total Electron Content ◽  
Space Weather ◽  
Support Vector ◽  
Electron Content ◽  
X Rays ◽  
Total Electron ◽  
Ionospheric Total Electron Content ◽  
Weather Events ◽  
Weather Research

<p>Ground and space-based remote sensing technology is one of the most useful tools for near-space environment studies and space weather research. During the last decade, a considerable amount of efforts in space weather research is being devoted for developing the ability to predict the exact time and location of space weather events such as solar flares and X-rays bursts. Despite the fact that most of the natural factors of such events can be modeled numerically, it is still a challenging task to produce accurate predications due to insufficient detailed and real‐time data. Hence, space weather scientists are trying to learn patterns of previous data distribution using data mining and machine learning (ML) tools in order to accurately predict future space weather events. Here, we present a new methodology based on support vector machines (SVM) approach applied with ionospheric Total Electron Content (TEC) data, derived from worldwide GPS geodetic receiver network that predict B, C, M and X-class solar flare events. Experimental results indicate that the proposed method has the ability to predict solar flare events of X and M-class with 80-94% and 78-93% accuracy, respectively. However, it does not succeed in producing similar promising results for the small-size C and B-class flares.</p>

scholarly journals AnANN Model Trained on Regional Data in the Prediction of Particular Weather Conditions

2021 ◽  
Vol 11 (11) ◽  
pp. 4757
Author(s):  
Aleksandra Bączkiewicz ◽  
Jarosław Wątróbski ◽  
Wojciech Sałabun ◽  
Joanna Kołodziejczyk
Keyword(s):  
Atmospheric Pressure ◽  
Real Life ◽  
Real Data ◽  
Weather Conditions ◽  
Maximum Temperature ◽  
Air Masses ◽  
Weather Forecasts ◽  
Life Problems ◽  
The World ◽  
The City

Artificial Neural Networks (ANNs) have proven to be a powerful tool for solving a wide variety of real-life problems. The possibility of using them for forecasting phenomena occurring in nature, especially weather indicators, has been widely discussed. However, the various areas of the world differ in terms of their difficulty and ability in preparing accurate weather forecasts. Poland lies in a zone with a moderate transition climate, which is characterized by seasonality and the inflow of many types of air masses from different directions, which, combined with the compound terrain, causes climate variability and makes it difficult to accurately predict the weather. For this reason, it is necessary to adapt the model to the prediction of weather conditions and verify its effectiveness on real data. The principal aim of this study is to present the use of a regressive model based on a unidirectional multilayer neural network, also called a Multilayer Perceptron (MLP), to predict selected weather indicators for the city of Szczecin in Poland. The forecast of the model we implemented was effective in determining the daily parameters at 96% compliance with the actual measurements for the prediction of the minimum and maximum temperature for the next day and 83.27% for the prediction of atmospheric pressure.

scholarly journals The Complex Space Weather Events of September 2017

2019 ◽  
Author(s):  
Rajkumar Hajra ◽  
Bruce, T. Tsurutani ◽  
Gurbax, S. Lakhina
Keyword(s):  
Space Weather ◽  
Complex Space ◽  
Weather Events
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