Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 6, 2013 at 04:45 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update November 2, 2013)] [Cycle 24 progress (last update November 2, 2013) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update November 2, 2013)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update November 2, 2013)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update November 3, 2013)]

[POES auroral activity level since October 2009 - updated January 26, 2013]
[Solar polar fields vs solar cycles - updated November 2, 2013]
[Presentation 3rd SSN Workshop, Tucson, 2013 (pdf)]

Recent activity

The geomagnetic field was quiet on November 5. Solar wind speed at SOHO ranged between 307 and 430 km/s.

Solar flux measured at 20h UTC on 2.8 GHz was 148.5 (increasing 35.1 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 119.9. The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 3.6). Three hour interval K indices: 21110001 (planetary), 11221212 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time) spots were observed in 11 active regions in 2K resolution (SN: 303) and 7 active regions in 1K resolution (SN: 161) SDO images on the visible solar disk.

Region 11884 [S15W51] decayed slowly and was mostly quiet.
Region 11887 [N20W19] decayed in the trailing spot section and was quiet.
Region 11889 [S19W16] displayed only minor changes and was mostly quiet.
Region 11890 [S11E38] still has a strong magnetic delta structure in the eastern part of the largest trailing penumbra. A new magnetic delta has formed in the south of the leading penumbra. Further M and X class flares are likely.
C5+ flares: impulsive M2.5/1F 08:17, impulsive C8.0 at 11:58, impulsive M1.0 at 18:13, C6.9 at 21:13, impulsive X3.3/1B at 22:12 UTC. No significant CMEs were observed after any of these events.

Spotted regions not numbered by SWPC:
S2796 [N08E06] reemerged with penumbra spots.
S2802 [S10W26] was quiet and stable.
S2803 [N05E40] regained trailing penumbra spots.
S2805 [S24W43] reemerged with a penumbra spot.
New region S2808 [N18E26] emerged with a penumbra spot.
New region S2809 [S17E03] emerged with penumbra spots.
New region S2810 [N01W04] emerged with a penumbra spot.

Coronal mass ejections (CMEs)

November 3-4: No obviously Earth directed CMEs were observed in LASCO or STEREO imagery.
November 5: A CME was observed off the northeast limb and north pole after a filament eruption which began near 01:25 UTC. Preliminary analysis indicate that the CME was not Earth directed.

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 recurrent coronal hole (CH592) was in an Earth facing positon on October 31-November 3. A recurrent trans equatorial coronal hole (CH593) will likely rotate into an Earth facing position on November 7-8.

Coronal hole map

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

Forecast

The geomagnetic field is expected to be quiet to unsettled on November 6 due to weak coronal hole effects and quiet on November 7-8. On November 10-11 effects from CH593 could cause some unsettled and active intervals.

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 2K resolution) 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 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
11882 2013.10.23
2013.10.24
2     S09W89 0040 CAO    

rotated out of view

11883 2013.10.26       N04W69          

plage

location: N04W56

11884 2013.10.26 4 10 5 S12W49 0070 DSO DSO

location: S15W51

area: 0200

11885 2013.10.26 1     S18W55 0110 HAX       part of AR 11884
11887 2013.10.29
2013.10.30
16 38 16 N20W18 0120 DAI DAI

 

S2792 2013.10.30       S10W06           plage
S2796 2013.10.31   2 1 N08E06 0007   AXX    
S2797 2013.10.31       S05W57           plage
S2798 2013.11.01       S22W53           plage
11890 2013.11.01
2013.11.02
39 99 49 S11E36 0950 EKC EKC beta-gamma-delta

area: 1250

location: S11E38

11889 2013.11.02 12 28 18 S18W17 0110 DAI DAI  
S2800 2013.11.02       S08E21           plage
S2802 2013.11.02   3 1 S10W15 0008   BXO  
S2803 2013.11.03   8   N05E40 0016   AXX  
S2804 2013.11.03       N13W36           plage
S2805 2013.11.03   1   S24W43 0003   AXX    
S2806 2013.11.03       S09W27           plage
S2808 2013.11.05   1 1 N18E26 0004   AXX    
S2809 2013.11.05   2   S17E03 0006   BXO    
S2810 2013.11.05   1   N01W04 0003   AXX    
Total spot count: 74 193 91  
Sunspot number: 134 303 161  (total spot count + 10 * number of spotted regions)
Weighted SN: 109 218 116  (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): 80 106 89 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)
2011.11 153.5 (cycle peak) 96.7 (cycle peak) 61.1 (+1.2) 5.55
2012.02 106.5 32.9 66.9 (+1.4)
likely cycle 24 max
8.81
2012.07 133.9 66.5 57.8 (-1.1) 13.90
2012.08 115.4 63.0 58.2 (+0.4) 7.96
2012.09 122.9 61.4 58.1 (-0.1) 8.07
2012.10 123.3 53.3 58.6 (+0.5) 9.97
2012.11 121.3 61.8 59.7 (+1.1) 7.08
2012.12 108.6 40.8 59.6 (-0.1) 3.44
2013.01 127.1 62.9 58.7 (-0.9) 4.69
2013.02 104.3 38.0 58.4 (-0.3) 6.11
2013.03 111.3 57.9 57.5 (-0.9) 10.56
2013.04 124.8 72.4 57.9 (+0.4) 5.40
2013.05 131.4 78.7 (59.3 projected, +1.4) 9.73
2013.06 110.1 52.5 (59.7 projected, +0.4) 12.60
2013.07 115.5 57.0 (60.0 projected, +0.3) 9.47
2013.08 114.6 66.0 (60.3 projected, +0.3) 8.27
2013.09 102.6 36.9 (60.2 projected, -0.1) 5.23
2013.10  132.1 85.6 (58.7 projected, -1.5) 7.65
2013.11  145.3 (1) 21.5 (2A) / 129.0 (2B) / 84.4 (2C) (56.6 projected, -2.1) (4.2)

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 the 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.