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A Comparison of Flare Forecasting Methods. III. Systematic Behaviors of Operational Solar Flare Forecasting SystemsLeka, K.D., Park, S-H., Kusano, K., Andries, J., Barnes, G., Bingham, S., Bloomfield, D.S., McCloskey, A.E., Delouille, V., Falconer, D., Gallagher, P.T., Georgoulis, M.K., Kubo, Y., Lee, K., Lee, S., Lobzin, V., Mun, J., Murray, S.A., Nageem, T.A.M.H., Qahwaji, Rami S.R., Sharpe, M., Steenburgh, R., Steward, G., Terkilsden, M. 08 October 2019 (has links)
Yes / A workshop was recently held at Nagoya University (31 October – 02 November
2017), sponsored by the Center for International Collaborative Research, at the Institute for Space-Earth Environmental Research, Nagoya University, Japan, to quantitatively compare the performance of today’s operational solar flare forecasting facilities.
Building upon Paper I of this series (Barnes et al. 2016), in Paper II (Leka et al. 2019)
we described the participating methods for this latest comparison effort, the evaluation methodology, and presented quantitative comparisons. In this paper we focus on
the behavior and performance of the methods when evaluated in the context of broad
implementation differences. Acknowledging the short testing interval available and the
small number of methods available, we do find that forecast performance: 1) appears to
improve by including persistence or prior flare activity, region evolution, and a human
“forecaster in the loop”; 2) is hurt by restricting data to disk-center observations; 3)
may benefit from long-term statistics, but mostly when then combined with modern
data sources and statistical approaches. These trends are arguably weak and must be
viewed with numerous caveats, as discussed both here and in Paper II. Following this
present work, we present in Paper IV a novel analysis method to evaluate temporal
patterns of forecasting errors of both types (i.e., misses and false alarms; Park et al.
2019). Hence, most importantly, with this series of papers we demonstrate the techniques for facilitating comparisons in the interest of establishing performance-positive
methodologies. / We wish to acknowledge funding from the Institute for Space-Earth Environmental Research, Nagoya University for supporting the workshop and its participants. We would also like to acknowledge the “big picture” perspective brought by Dr. M. Leila Mays during her participation in the workshop. K.D.L. and G.B. acknowledge that the DAFFS and DAFFS-G tools were developed under NOAA SBIR contracts WC-133R-13-CN-0079 (Phase-I) and WC-133R-14-CN-0103 (PhaseII) with additional support from Lockheed-Martin Space Systems contract #4103056734 for Solar-B FPP Phase E support. A.E.McC. was supported by an Irish Research Council Government of Ireland Postgraduate Scholarship. D.S.B. and M.K.G were supported by the European Union Horizon 2020 research and innovation programme under grant agreement No. 640216 (FLARECAST project; http://flarecast.eu). MKG also acknowledges research performed under the A-EFFort project and subsequent service implementation, supported under ESA Contract number 4000111994/14/D/ MPR. S. A. M. is supported by the Irish Research Council Postdoctoral Fellowship Programme and the US Air Force Office of Scientific Research award FA9550-17-1-039. The operational Space Weather services of ROB/SIDC are partially funded through the STCE, a collaborative framework funded by the Belgian Science Policy Office.
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Small-scale structures in the upper atmosphere of the SunBarczynski, Krzysztof 11 April 2017 (has links)
No description available.
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Prediction of Solar Activity from Solar Background Magnetic Field Variations in Cycles 21-23Shepherd, Simon J., Zharkov, S.I., Zharkova, Valentina V. January 2014 (has links)
yes / A comprehensive spectral analysis of both the solar background magnetic field (SBMF) in cycles 21-23 and the sunspot magnetic field in cycle 23 reported in our recent paper showed the presence of two principal components (PCs) of SBMF having opposite polarity, e. g., originating in the northern and southern hemispheres, respectively. Over a duration of one solar cycle, both waves are found to travel with an increasing phase shift toward the northern hemisphere in odd cycles 21 and 23 and to the southern hemisphere in even cycle 22. These waves were linked to solar dynamo waves assumed to form in different layers of the solar interior. In this paper, for the first time, the PCs of SBMF in cycles 21-23 are analyzed with the symbolic regression technique using Hamiltonian principles, allowing us to uncover the underlying mathematical laws governing these complex waves in the SBMF presented by PCs and to extrapolate these PCs to cycles 24-26. The PCs predicted for cycle 24 very closely fit (with an accuracy better than 98%) the PCs derived from the SBMF observations in this cycle. This approach also predicts a strong reduction of the SBMF in cycles 25 and 26 and, thus, a reduction of the resulting solar activity. This decrease is accompanied by an increasing phase shift between the two predicted PCs (magnetic waves) in cycle 25 leading to their full separation into the opposite hemispheres in cycle 26. The variations of the modulus summary of the two PCs in SBMF reveals a remarkable resemblance to the average number of sunspots in cycles 21-24 and to predictions of reduced sunspot numbers compared to cycle 24: 80% in cycle 25 and 40% in cycle 26.
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Modélisation hybride du cycle d’activité solaire : évolution couplée du flux magnétique photosphérique et de la dynamo interneSt-Laurent-Lemerle, Alexandre 08 1900 (has links)
No description available.
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