Evaluation of the Solar Quiet Reference Field (SQRF) Model for Space Weather Applications in the South America Magnetic Anomaly

Abstract In the present work, we evaluate the accuracy of the Solar Quiet Reference Field (SQRF) model for estimating and predicting the geomagnetic solar quiet (Sq) daily field variation in the South America Magnetic Anomaly (SAMA) region. This model is based on the data set of fluxgate magnetometers from 12 magnetic stations of the Embrace Magnetometer Network (Embrace MagNet) from 2010 to 2018. The model predicts the monthly average horizontal field of the geomagnetic quiet (Sq-H) daily variation solving a set of equations for the specified geographic coordinates in terms of the solar cycle activity, the day of the year, and the universal time. We carried out two comparisons between the prediction and observational data of the Sq-H field. The first part attempts to evaluate the accuracy for estimating the Sq-H field over Medianeira (25.30°S, 54.11°W, dip angle: -33.45°) by using linear interpolation on the SQRF coefficients. The second part of the analysis attempts to evaluate the accuracy for predicting the quiet daily field variation over Cachoeira Paulista (22.70°S, 45.01°W, dip angle: -38.48°). The results of the prediction for both locations show that this empirical model presents a good agreement with the Sq-H field obtained from the magnetic field data. The accuracy of the SQRF model (high correlation, r >0.9) provides a high potential for estimating and predicting geomagnetic quiet daily field variation for space weather applications.

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Evaluation of the Solar Quiet Reference Field (SQRF) Model for Space Weather Applications in the South America Magnetic Anomaly

10.21203/rs.3.rs-56044/v3 ◽

2021 ◽

Author(s):

Sony Su Chen ◽

Clezio Marcos Denardini ◽

Láysa C. A. Resende ◽

Ronan A. J. Chagas ◽

Juliano Moro ◽

...

Keyword(s):

South America ◽

Magnetic Anomaly ◽

Space Weather ◽

Weather Prediction ◽

Magnetic Data ◽

Field Variation ◽

Reference Field ◽

The South ◽

Data Set ◽

Dip Angle

Abstract In the present work, we evaluate the accuracy of the Solar Quiet Reference Field (SQRF) model for estimating and predicting the geomagnetic solar quiet (Sq) daily field variation in the South America Magnetic Anomaly (SAMA) region. This model is based on the data set of fluxgate magnetometers from 12 magnetic stations of the Embrace Magnetometer Network (Embrace MagNet) from 2010 to 2018. The model predicts the monthly average horizontal field of the geomagnetic quiet (Sq-H) daily variation solving a set of equations for the specified geographic coordinates in terms of the solar cycle activity, the day of the year, and the universal time. We carried out two comparisons between the prediction and observational data of the Sq-H field. The first part attempts to evaluate the accuracy for estimating the Sq-H field over Medianeira (MED, 25.30°S, 54.11°W, dip angle: -33.45°) by using linear interpolation on the SQRF coefficients and compared it with the data collected from April to December in 2018. It worth mentioning that none of the datasets collected at MED is part of the dataset used to build the SQRF model, hence the need to do interpolation. The second part of the analysis attempts to evaluate the accuracy for predicting the quiet daily field variation over Cachoeira Paulista (CXP, 22.70°S, 45.01°W, dip angle: -38.48°). The dataset collected at CXP prior to the period analyzed in the present work is part of the dataset used to build the SQRF model. Thus, the accuracy of the prediction is tested using magnetic data outside the time interval considered in the model. The results of the prediction for both locations show that the outputs from this empirical model present a good agreement with the Sq-H field obtained from the magnetic field data. The accuracy of the SQRF model (high correlation, r>0.9) provides a high potential for estimating and predicting geomagnetic quiet daily field variation for space weather applications, improving the scientific insight and capability of space weather prediction centers to predict the variability of the regular solar quiet field variation as reference conditions, which may include areas with no measurements.

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Evaluation of the Solar Quiet Reference Field (SQRF) model for space weather applications in the South America Magnetic Anomaly

Earth Planets and Space ◽

10.1186/s40623-021-01382-8 ◽

2021 ◽

Vol 73 (1) ◽

Author(s):

Sony Su Chen ◽

Clezio Marcos Denardini ◽

Láysa Cristina Araujo Resende ◽

Ronan Arraes Jardim Chagas ◽

Juliano Moro ◽

...

Keyword(s):

South America ◽

Magnetic Anomaly ◽

Space Weather ◽

Weather Prediction ◽

Magnetic Data ◽

Field Variation ◽

Reference Field ◽

The South ◽

Data Set ◽

Dip Angle

AbstractIn the present work, we evaluate the accuracy of the Solar Quiet Reference Field (SQRF) model for estimating and predicting the geomagnetic solar quiet (Sq) daily field variation in the South America Magnetic Anomaly (SAMA) region. This model is based on the data set of fluxgate magnetometers from 12 magnetic stations of the Embrace Magnetometer Network (Embrace MagNet) from 2010 to 2018. The model predicts the monthly average horizontal field of the geomagnetic quiet (Sq-H) daily variation solving a set of equations for the specified geographic coordinates in terms of the solar cycle activity, the day of the year, and the universal time. We carried out two comparisons between the prediction and observational data of the Sq-H field. The first part attempts to evaluate the accuracy for estimating the Sq-H field over Medianeira (MED, 25.30° S, 54.11° W, dip angle: − 33.45°) by using linear interpolation on the SQRF coefficients and comparing it with the data collected from April to December in 2018. None of the datasets collected at MED is part of the dataset used to build the SQRF model. The second part of the analysis attempts to evaluate the accuracy for predicting the quiet daily field variation over Cachoeira Paulista (CXP, 22.70° S, 45.01° W, dip angle: − 38.48°). The dataset collected at CXP before the period analyzed in the present work is part of the dataset used to build the SQRF model. Thus, the prediction accuracy is tested using magnetic data outside the time interval considered in the model. The prediction results for both locations show that this empirical model’s outputs present a good agreement with the Sq-H field obtained from the ground-based magnetometer measurements. The accuracy of the SQRF model (high correlation, r > 0.9) indicates a high potential for estimating and predicting geomagnetic quiet daily field variation. Concerning space weather applications, the model improves the scientific insight and capability of space weather prediction centers to predict the variability of the regular solar quiet field variation as reference conditions, which may include areas with no measurements.

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Performance of the IRI-2016 at the Brazilian low-latitude ionosphere over the South America Magnetic Anomaly during solar minimum

10.5194/angeo-2019-126 ◽

2019 ◽

Author(s):

Juliano Moro ◽

Jiyao Xu ◽

Clezio Marcos De Nardin ◽

Laysa Cristina Araújo Resende ◽

Régia Pereira Silva ◽

...

Keyword(s):

South America ◽

Magnetic Anomaly ◽

Critical Frequency ◽

Peak Height ◽

The South ◽

Iri Model ◽

Radio Science ◽

Critical Frequency Fof2 ◽

Dip Angle ◽

Navigation Signals

Abstract. In this work we analyse the ionograms obtained by the recent Digisonde installed in Santa Maria (29.7º S, 53.7º W, dip angle = − 37º), Brazil, to calculate the monthly averages of the F2 layer critical frequency (foF2), its peak height (hmF2), and the E-region critical frequency (foE) acquired during geomagnetically quiet days from September 2017 to August 2018. The monthly averages are compared to the 2016 version of the International Reference Ionosphere (IRI) model predictions in order to study its performance close to the center of the South America Magnetic Anomaly (SAMA), which is a region particularly important for High Frequency (HF) ground-to-satellite navigation signals. The foF2 estimated with the Consultative Committee International Radio (CCIR) and International Union of Radio Science (URSI) options predicts well throughout the year. Whereas, for hmF2, it is recommended to use the SHU-2015 option instead of the other available options (AMTB2013 and BSE-1979). The IRI-2016 model outputs for foE and the observations presented very good agreements.

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Performance of the IRI-2016 over Santa Maria, a Brazilian low-latitude station located in the central region of the South American Magnetic Anomaly (SAMA)

Annales Geophysicae ◽

10.5194/angeo-38-457-2020 ◽

2020 ◽

Vol 38 (2) ◽

pp. 457-466

Author(s):

Juliano Moro ◽

Jiyao Xu ◽

Clezio Marcos Denardini ◽

Laysa Cristina Araújo Resende ◽

Régia Pereira Silva ◽

...

Keyword(s):

Magnetic Anomaly ◽

Critical Frequency ◽

Peak Height ◽

The South ◽

Iri Model ◽

Radio Science ◽

Critical Frequency Fof2 ◽

Dip Angle ◽

Navigation Signals ◽

Santa Maria

Abstract. In this work we analyze the ionograms obtained by the recent digisonde installed in Santa Maria (29.7∘ S, 53.7∘ W, dip angle = −37∘), Brazil, to calculate the monthly averages of the F2 layer critical frequency (foF2), its peak height (hmF2), and the E-region critical frequency (foE) acquired during geomagnetically quiet days from September 2017 to August 2018. The monthly averages are compared to the 2016 version of the International Reference Ionosphere (IRI) model predictions in order to study its performance close to the center of the South America Magnetic Anomaly (SAMA), which is a region particularly important for high-frequency (HF) ground-to-satellite navigation signals. The foF2 estimated with the Consultative Committee International Radio (CCIR) and International Union of Radio Science (URSI) options makes good predictions throughout the year, whereas, for hmF2, it is recommended to use the SHU-2015 option instead of the other available options (AMTB2013 and BSE-1979). The IRI-2016 model outputs for foE and the observations presented very good agreement.

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Occurrence and Modeling Examination of Sporadic‐ E Layers in the Region of the South America ( Atlantic ) Magnetic Anomaly

Journal of Geophysical Research Space Physics ◽

10.1029/2018ja026397 ◽

2019 ◽

Vol 124 (11) ◽

pp. 9676-9694 ◽

Cited By ~ 1

Author(s):

Fredson Conceição‐Santos ◽

Marcio T. A. H. Muella ◽

Laysa C. A. Resende ◽

Paulo R. Fagundes ◽

Vania F. Andrioli ◽

...

Keyword(s):

South America ◽

Magnetic Anomaly ◽

The South ◽

Sporadic E Layers ◽

Sporadic E

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The South America VLF Network (SAVNET): Providing new ground-based diagnostics of space weather conditions

2011 XXXth URSI General Assembly and Scientific Symposium ◽

10.1109/ursigass.2011.6050912 ◽

2011 ◽

Cited By ~ 1

Author(s):

Jean-Pierre Raulin

Keyword(s):

South America ◽

Space Weather ◽

Weather Conditions ◽

The South

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The South America Advantage

SSRN Electronic Journal ◽

10.2139/ssrn.1911532 ◽

2011 ◽

Author(s):

Lynn E. Dellenbarger ◽

Lihong Zhu

Keyword(s):

South America ◽

The South

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Impact of enriched analyses on regional numerical forecasts over southeastern South America during SALLJEX

Revista Brasileira de Meteorologia ◽

10.1590/0102-778620100248 ◽

2014 ◽

Vol 29 (3) ◽

pp. 315-330

Author(s):

Yanina García Skabar ◽

Matilde Nicolini

Keyword(s):

Data Assimilation ◽

South America ◽

Atmospheric Modeling ◽

South American ◽

The South ◽

Low Level ◽

Positive Effects ◽

Accumulated Rainfall ◽

Low Level Jet ◽

The Impact

During the warm season 2002-2003, the South American Low-Level Jet Experiment (SALLJEX) was carried out in southeastern South America. Taking advantage of the unique database collected in the region, a set of analyses is generated for the SALLJEX period assimilating all available data. The spatial and temporal resolution of this new set of analyses is higher than that of analyses available up to present for southeastern South America. The aim of this paper is to determine the impact of assimilating data into initial fields on mesoscale forecasts in the region, using the Brazilian Regional Atmospheric Modeling System (BRAMS) with particular emphasis on the South American Low-Level Jet (SALLJ) structure and on rainfall forecasts. For most variables, using analyses with data assimilated as initial fields has positive effects on short term forecast. Such effect is greater in wind variables, but not significant in forecasts longer than 24 hours. In particular, data assimilation does not improve forecasts of 24-hour accumulated rainfall, but it has slight positive effects on accumulated rainfall between 6 and 12 forecast hours. As the main focus is on the representation of the SALLJ, the effect of data assimilation in its forecast was explored. Results show that SALLJ is fairly predictable however assimilating additional observation data has small impact on the forecast of SALLJ timing and intensity. The strength of the SALLJ is underestimated independently of data assimilation. However, Root mean square error (RMSE) and BIAS values reveal the positive effect of data assimilation up to 18-hours forecasts with a greater impact near higher topography.

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