MAG4 versus alternative techniques for forecasting active region flare productivity
نویسندگان
چکیده
MAG4 is a technique of forecasting an active region's rate of production of major flares in the coming few days from a free magnetic energy proxy. We present a statistical method of measuring the difference in performance between MAG4 and comparable alternative techniques that forecast an active region's major-flare productivity from alternative observed aspects of the active region. We demonstrate the method by measuring the difference in performance between the "Present MAG4" technique and each of three alternative techniques, called "McIntosh Active-Region Class," "Total Magnetic Flux," and "Next MAG4." We do this by using (1) the MAG4 database of magnetograms and major flare histories of sunspot active regions, (2) the NOAA table of the major-flare productivity of each of 60 McIntosh active-region classes of sunspot active regions, and (3) five technique performance metrics (Heidke Skill Score, True Skill Score, Percent Correct, Probability of Detection, and False Alarm Rate) evaluated from 2000 random two-by-two contingency tables obtained from the databases. We find that (1) Present MAG4 far outperforms both McIntosh Active-Region Class and Total Magnetic Flux, (2) Next MAG4 significantly outperforms Present MAG4, (3) the performance of Next MAG4 is insensitive to the forward and backward temporal windows used, in the range of one to a few days, and (4) forecasting from the free-energy proxy in combination with either any broad category of McIntosh active-region classes or any Mount Wilson active-region class gives no significant performance improvement over forecasting from the free-energy proxy alone (Present MAG4). KEY POINTS Quantitative comparison of performance of pairs of forecasting techniques Next MAG4 forecasts major flares more accurately than Present MAG4 Present MAG4 forecast outperforms McIntosh AR Class and total magnetic flux.
منابع مشابه
Microdose GnRH Agonist Flare-Up versus Ultrashort GnRH Agonist Combined with Fixed GnRH Antagonist in Poor Responders of Assisted Reproductive Techniques Cycles
متن کامل
Statistical Models for Solar Flare Interval Distribution in Individual Active Regions
This article discusses statistical models for solar flare interval distribution in individual active regions. We analyzed solar flare data in 55 active regions that are listed in the Geosynchronous Operational Environmental Satellite (GOES) soft X-ray flare catalog for the years from 1981 to 2005. We discuss some problems with a conventional procedure to derive probability density functions fro...
متن کاملFlare productivity of newly-emerged paired and isolated solar active regions
Aims. We investigate whether sunspot regions that emerge near existing ones are more flare productive than those that emerge isolated. Methods. We analyse a sample of 2115 new regions obtained from the USAF/Mount Wilson catalogue of sunspot regions. For our analysis we use AstroGrid, a Virtual Observatory developed in the UK, to build a series of workflows that perform queries to catalogues of ...
متن کاملToward an Efficient Prediction of Solar Flares: Which Parameters, and How?
Solar flare prediction has become a forefront topic in contemporary solar physics, with numerous published methods relying on numerous predictive parameters, that can even be divided into parameter classes. Attempting further insight, we focus on two popular classes of flare-predictive parameters, namely multiscale (i.e., fractal and multifractal) and proxy (i.e., morphological) parameters, and...
متن کاملStudy of Magnetic Helicity in Solar Active Regions and Its Relationship with Solar Eruptions
STUDY OF MAGNETIC HELICITY IN SOLAR ACTIVE REGIONS AND ITS RELATIONSHIP WITH SOLAR ERUPTIONS by Sung-Hong Park It is generally believed that eruptive phenomena in the solar atmosphere such as solar flares and coronal mass ejections (CMEs) occur in solar active regions with complex magnetic structures. The magnetic complexity is quantified in terms of twists, kinks, and interlinkages of magnetic...
متن کامل