Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 15, 2012 at 05:45 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 major storm on November 14. Solar wind speed at SOHO ranged between 351 and 527 km/s under the influence of CME and CH effects.

Solar flux measured at 20h UTC on 2.8 GHz was 142.1 (increasing 4.5 over the last solar rotation). The Potsdam WDC planetary A index was 43 (STAR Ap - based on the mean of three hour interval ap indices: 42.6). Three hour interval K indices: 66654212 (planetary), 56554322 (Boulder).

The background x-ray flux was at the class B4 level.

At midnight UTC the visible solar disk had 15 spotted active regions (in 2K resolution SDO images).

Region 11609 [S17W31] was quiet and stable.
Region 11610 [S23W37] decayed slowly and quietly.
Region 11611 [N11W13] decayed slowly and was mostly quiet.
Region 11612 [N07W03] gained a few spots and was quiet.
Region 11613 [S24E19] decayed slowly and has only minor polarity intermixing. Flare: impulsive M1.1 at 04:04 UTC.
Region 11614 [N14E32] developed again and has polarity intermixing. An M class flare is possible.
Region 11615 [N07E20] was quiet and stable.
New region 11616 [N18E62] rotated into view on November 13 and was numbered by SWPC the next day.

Spotted regions not numbered by NOAA/SWPC:
S2048 [N25W26] decayed and could soon become spotless.
S2049 [S19E09] was quiet and stable.
New region S2051 [S12E37] emerged with a tiny spot.
New region S2052 [N42E30] emerged at a high latitude with a single spot.
New region S2053 [S32E29] emerged with tiny spots.
New region S2054 [S18W46] emerged with a tiny spot.
New region S2055 [S20E39] emerged with tiny spots.

Coronal mass ejections (CMEs)

November 12-14: 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

No obvious coronal holes are currently in or near Earth facing positions.

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 poor. Propagation on long distance northeast-southwest paths is fair.

Forecast

The geomagnetic field is expected to be quiet to unsettled on November 15-17.

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
11608 2012.11.04
2012.11.05
      S20W59           plage
11609 2012.11.05
2012.11.06
  7 1 S14W38 0000   BXO  
11610 2012.11.06
2012.11.07
14 24 10 S23W36 0210 EAI ESO  

 

S2038 2012.11.07       S06W48           plage
11611 2012.11.07
2012.11.08
10 18 7 N13W14 0160 DSO DSO

area: 0270

S2040 2012.11.07       N10W50         plage
11612 2012.11.08 1 4 2 N08W05 0050 HSX HSX area: 0140

location: N07W03

S2041 2012.11.08       N04W51           plage
11613 2012.11.09
2012.11.11
8 16 6 S23E18 0120 DSO DSO beta-gamma

area: 0200

location: S25E33

11614 2012.11.10
2012.11.11
13 34 19 N16E31 0240 DAI DAC beta-gamma

area: 0380

location: N14E32

11615 2012.11.11 8 10 4 N09E19 0080 DSO DRO

location: N07E20

area: 0040

S2045 2012.11.11       S15W19           plage
S2047 2012.11.12       S09W18           plage
S2048 2012.11.12   1   N25W26 0000   AXX reversed polarities
S2049 2012.11.13   2 2 S19E09 0010   BXO  
11616 2012.11.13
2012.11.14
2 15 5 N21E61 0070 DRO CRO location: N18E62
S2051 2012.11.14   1   S12E37 0000   AXX    
S2052 2012.11.14   1 1 N42E30 0000   AXX    
S2053 2012.11.14   2   S32E29 0000   AXX    
S2054 2012.11.14   1 1 S18W46 0000   AXX    
S2055 2012.11.14   4 1 S20E39 0000   AXX    
Total spot count: 56 140 59  
Sunspot number: 126 290 179  (total spot count + 10 * number of spotted regions)
Weighted SN: 89 171 90  (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): 76 102 98 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
2012.11 113.4 (1) 36.0 (2A) / 77.1 (2B) / 54.8 (2C) (61.2 projected, -0.3) (10.21)

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.