1 / 27

Solar Activity Statistical Analysis: Understanding Sunspot Features and Flare Occurrences

Explore solar activity through statistical analysis of sunspot features and flare occurrences. Discover patterns, asymmetries, and correlations in solar data for better understanding of solar dynamics. Future plans include expanding database and in-depth analysis of solar cycles.

ctaunton
Download Presentation

Solar Activity Statistical Analysis: Understanding Sunspot Features and Flare Occurrences

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Understanding solar activity using statistical propertiesof solar features in SFCs and flare occurrences V.V. Zharkova1, and S. Zharkov2 1- Bradford University, 2 – Sheffield University http://solar.inf.brad.ac.uk

  2. Catalogue Description (Zharkova et al., 2005, ASR) http://solar.inf.brad.ac.uk • Observational Parameters: • Date of observation, resolution; determined quiet sun intensity; • Feature Parameters: • Gravity center (proj & Carrington), area, diameter, umbra size, bounding rectangle, intensity statistics, magnetic information • Raster Scans (bounding rectangle mask): • reconstructed: pixel values equal to 0 corresponding to quiet Sun, 1 to penumbra, 2 to umbra • Sunspot Catalogue (from 1996-05-19 19:08:35 to 2005-05-31 19:51:32) • About 10000 observation processed • ~370000 sunspots and 100 000 ARs stored • SSW software: • Catalogue Search -> VOTable -> IDL SSW -> features reconstructed, over plotted

  3. Sunspot Detection (Zharkov et al., 2005, Eurasip J.) detected edges & low intensity regions => <= original image <ROI result >

  4. Automatically detected active regions with region growing (left) and the ARs from Big Bear Solar Observatory (right)

  5. Search page sample

  6. SFC Example

  7. Sunspot areas comparison USAF SOON / SFC – 96% correlation

  8. N-S asymmetry in daily s/s areas

  9. Daily areas covered by ARs in N-S hemispheres

  10. Daily mean intensities of active regions in 1996-2005

  11. North South Asymmetry(averaged by 170 days) (N-S)/(N+S) (ss –top, ar –bottom)

  12. North South AsymmetryCumulative Area (Solar Cycle 23)ss –left, ar -right Temmer, Veronig Hanslmeier, A&A 2001, SoPh 2003

  13. North-South asymmetry in cumulative areas (s/s left and ar right)

  14. Variations of Flare numbers and sunspot areas in cycle 23

  15. Sunspot statistics Cumulitative areas: North – solid blue line, South – dashed navy line Asymmetry in cumulitative areas averaged by 4 month (purple), 1 year (navy) and 3 years (blue)

  16. Flare statistics: N-S and W-E asymmetriesJoshi ad Pant, 2005; Zharkova and Zharkov, 2006 Cumulitative areas: North – blue line, South – navy line Cumulitative areas: West – purple line, East – pink line

  17. Latitudinal distributions flare occurrences

  18. Sunspot and flare butterfly diagrams in the cycle 23

  19. Latitude distributions of flare occurrences (averaged by 30,180,360 & 1080 days)

  20. Flare latitude occurrences in the cycle 23 – correlation with AR N-S asymmetry (0.85)

  21. Longitude distributions of flare occurrences averaged by 30,90,180 & 1080 days –active longitude of 200o

  22. Sunspot active longitudes

  23. Butterfly diagram for flare occurrences in cycle 23 (L=200o, =15o, 4o, -5o, -15o)

  24. Force-free global magnetic configuration -17/03/02 (courtesy of Y.Yan, 2005)

  25. Conclusions • In the cycle 23 solar flare occurrences show a moderate (0.62) correlation with sunspot area variations and higher with AR areas (0.81) • N-S asymmetry is a common pattern in s/s and AR (plages) areas and flare occurrences with different levels of periodicity (2 and 9 (11?) years) • Flare latitudinal distributions show maxima at the latitudes of about 15-20o • Flare occurrences averaged by a year show the ‘active’ latitudes on 5o, 15o and -15o and -5o • Essential W-E asymmetry in the cumulitative flare occurences • This W-E asymmetry is distinctly seen in the averaged flare longitudinal distributions at the longitude of 200o.

  26. Thank you!

  27. Future Planshttp://solar.inf.brad.ac.uk • Investigate data further • Database relatively small (for long-term statistics), but will only grow • Interested in additional input – possible statistics to be extracted, offered, other data sources, other features & feature parameters • Filling the data gaps & periodogram analysis • Latitude and longitude distributions • Extend the statistical analysis of the current cycle and possible links with solar dynamo models • Sunspot classification into groups • Extraction of Sunspot Group tilt and its variation with the Solar Cycle • More ????

More Related