Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 14, 2012 at 05:30 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update November 1, 2012)] [Cycle 24 progress (last update November 1, 2012) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update November 1, 2012)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update November 1, 2012)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update November 4, 2012)]

[POES auroral activity level since October 2009 - updated October 7, 2012]
[Solar polar fields vs solar cycles - updated June 27, 2011]

Recent activity

The geomagnetic field was quiet to minor storm on November 13. Solar wind speed at SOHO ranged between 346 and 570 km/s, mostly under the influence of CME effects. The interplanetary magnetic field was mostly northwards for the first half of the day, then swung gradually more southwards and was strongly southwards by the end of the day. This caused major geomagnetic storming early on November 14.

Solar flux measured at 20h UTC on 2.8 GHz was 146.2 (increasing 11.2 over the last solar rotation). The Potsdam WDC planetary A index was 22 (STAR Ap - based on the mean of three hour interval ap indices: 21.9). Three hour interval K indices: 54242334 (planetary), 33233422 (Boulder).

The background x-ray flux was at the class B6 level.

At midnight UTC the visible solar disk had 11 spotted active regions (in 2K resolution SDO images).

Region 11609 [S17W17] decayed slowly and quietly.
Region 11610 [S24W24] decayed slowly and was quiet.
Region 11611 [N11E01] developed slowly in the trailing spot section with weak polarity intermixing observed.
Region 11612 [N07E10] was quiet and stable.
Region 11613 [S25E33] decayed and lost the largest magnetic delta structure after the last of the 3 M class events produced during the day. There's still a weak magnetic delta structure present in a southern penumbra. Flares: impulsive M6.0 at 02:04, impulsive M2.5 at 05:50, impulsive M2.8 at 20:54 UTC.
Region 11614 [N14E46] matured and simplified magnetically.
Region 11615 [N07E33] developed slowly and was quiet.

Spotted regions not numbered by NOAA/SWPC:
S2040 [N10W37] was quiet and stable.
S2048 [N25W14] lost the leader spot and gained a trailer spot in this reversed polarities region.
New region S2049 [S16E18] emerged with tiny spots.
New region S2050 [N18E75] rotated into view. Although there are no impressive spots, opposite polarity spots are fairly close centrally.

Coronal mass ejections (CMEs)

November 11-13: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.

Coronal holes

Coronal hole history (since October 2002)
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago

A trans equatorial coronal hole (CH545) was in an Earth facing position on November 10.

Coronal hole map

The above coronal hole map is based on a method where coronal holes are detected automatically. While the method may need some fine tuning, it has significant advantages over detecting coronal holes manually. The main improvement is the ability to detect coronal holes at and just beyond the solar limbs. Early results using this method for SDO images over a span of several weeks indicate a good match between coronal holes observed over the visible disk and their extent and position at the east and west limbs. Note that the polar coronal holes are easily detected using this method, the extent and intensity of both CHs are consistent with other data sources.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is very poor. Propagation on long distance northeast-southwest paths is fair to good.

Forecast

The geomagnetic field is expected to be quiet to major storm on November 14 due to CME effects and quiet to unsettled on November 15-16.

Coronal holes (1) Coronal mass ejection (2) M and X class flares (3)
     

1) Effects from a coronal hole could reach Earth within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability.

Active solar regions

Click on image for higher resolution image) Compare to the previous day's image. 0.5k image

When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue (blue-green) is positive.

Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.

Active region Date numbered
detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlay
Comment
SWPC STAR SDO SWPC STAR Current Previous
2K 1K
11606 2012.11.04       S15W80           plage
11608 2012.11.04
2012.11.05
      S20W45         plage
11609 2012.11.05
2012.11.06
  6   S14W24 0000   BXO  
11610 2012.11.06
2012.11.07
18 30 10 S24W23 0210 EKI ESI  

area: 0320

S2038 2012.11.07       S06W35           plage
11611 2012.11.07
2012.11.08
8 26 14 N12W00 190 DSO DSI beta-gamma

area: 0360

S2040 2012.11.07   5   N10W37 0000   AXX  
11612 2012.11.08 1 1 1 N08E08 0050 HSX HSX area: 0140

location: N07E10

S2041 2012.11.08       N04W38           plage
11613 2012.11.09
2012.11.11
6 19 7 S23E31 0160 DSO DSI beta-gamma-delta

area: 0220

location: S25E33

11614 2012.11.10
2012.11.11
13 22 9 N16E45 0220 DAI DSC area: 0380
11615 2012.11.11 2 14 9 N09E31 0020 CAO CRI

location: N07E33

S2045 2012.11.11       S15W06           plage
S2047 2012.11.12       S09W05         plage
S2048 2012.11.12   1 1 N25W14 0000   AXX reversed polarities
S2049 2012.11.13   3   S16E18 0000   BXO    
S2050 2012.11.13   7 3 N18E75 0040   CRO    
Total spot count: 48 134 54  
Sunspot number: 108 244 134  (total spot count + 10 * number of spotted regions)
Weighted SN: 83 165 85  (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)
Relative sunspot number (Wolf number): 65 85 74 k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for STAR SDO 2K, k = 0.55 for STAR SDO 1K

Monthly solar cycle data

Month Average measured solar flux International sunspot number (SIDC) Smoothed sunspot number Average ap
(3)
2011.09 133.8 78.0 59.5 (+0.5) 12.27
2011.10 137.3 88.0 59.9 (+0.4) 8.28
2011.11 153.5 96.7 61.1 (+1.2) 5.55
2011.12 141.3 73.0 63.4 (+2.3) 3.78
2012.01 132.5 58.3 65.5 (+2.1) 7.15
2012.02 106.5 32.9 66.9 (+1.4)
possible cycle 24 max
8.81
2012.03 114.7 64.3 66.8 (-0.1) 16.08
2012.04 113.0 55.2 64.6 (-2.2) 10.10
2012.05 121.5 69.0 (61.2 projected, -3.4) 7.06
2012.06 119.6 64.5 (58.8 projected, -2.4) 10.08
2012.07 133.9 66.5 (58.6 projected, -0.2) 13.90
2012.08 115.4 63.1 (60.4 projected, +1.8) 7.96
2012.09 122.9 61.5 (61.8 projected, +1.4) 8.07
2012.10 123.3 53.3 (61.5 projected, -0.3) 9.97
2012.11 111.1 (1) 31.8 (2A) / 73.4 (2B) / 53.9 (2C) (61.2 projected, -0.3) (7.72)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official SIDC international sunspot number is typically 30-50% lower. 2B) Boulder SN current month average to date. 2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international Potsdam WDC ap indices.

This report has been prepared by Jan Alvestad. It is based on analysis of data from whatever sources are available at the time the report is prepared. All time references are to the UTC day. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.