Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 7, 2013 at 05:55 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 6. Solar wind speed at SOHO ranged between 307 and 355 km/s.

Solar flux measured at 20h UTC on 2.8 GHz was 153.5 (increasing 32.8 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 120.4. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.1). Three hour interval K indices: 10110112 (planetary), 00111221 (Boulder).

The background x-ray flux was at the class B8 level.

At the time of counting spots (see image time) spots were observed in 9 active regions in 2K resolution (SN: 281) and 8 active regions in 1K resolution (SN: 179) SDO images on the visible solar disk.

Region 11884 [S16W67] decayed slowly and quietly.
Region 11887 [N20W32] decayed slowly and quietly.
Region 11889 [S18W29] decayed slowly and quietly.
Region 11890 [S11E24] still has a magnetic delta structure in the eastern part of the largest trailing penumbra while the other deltas disappeared. While the region has many spots magnetic complexity has decreased slowly over the last day. Further M class flares are likely.
C5+ flares: C8.6 at 08:51, M3.8/1N at 13:46 UTC.
New region 11891 [S18W11] emerged on November 5 and was numbered the next day by SWPC. The region has polarity intermixing and could produce C and minor M class flares.
New region 11892 [S05E69] emerged early in the day near the southeast limb.

Spotted regions not numbered by SWPC:
S2796 [N07W07] was quiet and stable.
S2803 [N05E27] decayed slowly and quietly.
New region S2813 [N18E14] emerged with penumbra spots.

 C5+ flare: M1.8 beginning at 23:44 and peaking at 00:02 UTC had its origin near the southwest limb and caused an enhancement in proton levels.

Coronal mass ejections (CMEs)

November 4, 6: No obviously Earth directed CMEs were observed in LASCO and 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. A relatively slow and unimpressive partial halo CME was observed after the X3 event late in the day.

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 trans equatorial coronal hole (CH593) will 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 due to enhanced proton levels. Propagation on long distance northeast-southwest paths is fair.

Forecast

The geomagnetic field is expected to be quiet to active on November 7. Effects from the CME associated with the X3 event late on Nov.5 could reach Earth on Nov.8-9 and cause unsettled to active intervals. 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
11883 2013.10.26       N04W83          

plage

location: N04W70

11884 2013.10.26 3 10 4 S12W62 0050 CSO DAO

location: S16W67

area: 0120

11885 2013.10.26 2     S18W69 0090 HAX       part of AR 11884
11887 2013.10.29
2013.10.30
11 22 14 N20W31 0090 DAI DSI

area: 0130

S2792 2013.10.30       S10W19           plage
S2796 2013.10.31   1   N07W07 0002   AXX  
11890 2013.11.01
2013.11.02
46 103 50 S11E23 0910 EKC EKC beta-gamma-delta

area: 1050

11889 2013.11.02 12 24 13 S18W30 0080 DAI DRI  
S2800 2013.11.02       S08E08           plage
S2802 2013.11.02       S10W39         plage
S2803 2013.11.03   3 1 N05E27 0006   BXO  
S2804 2013.11.03       N13W49           plage
S2805 2013.11.03       S24W56         plage
S2806 2013.11.03       S09W40           plage
11891 2013.11.05
2013.11.06
3 28 13 S18W11 0020 CAO DRI beta-gamma

area: 0100

S2810 2013.11.05       N01W17         plage
11892 2013.11.06 1 5 3 S05E67 0010 AXX CRO   area: 0025
S2813 2013.11.06   1 1 N18E14 0004   AXX    
Total spot count: 78 197 99  
Sunspot number: 148 287 179  (total spot count + 10 * number of spotted regions)
Weighted SN: 113 226 128  (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): 89 100 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)
2011.11 153.5 (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  146.7 (1) 25.6 (2A) / 132.1 (2B) / 85.9 (2C) (56.6 projected, -2.1) (4.0)

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.