Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 15, 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 very quiet on November 14. Solar wind speed at SOHO ranged between 337 and 393 km/s.

Solar flux measured at 20h UTC on 2.8 GHz was 175.8 (increasing 35.9 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 123.7. The Potsdam WDC planetary A index was 2 (STAR Ap - based on the mean of three hour interval ap indices: 2.3). Three hour interval K indices: 00010011 (planetary), 00022211 (Boulder).

The background x-ray flux was at the class B9 level.

At the time of counting spots (see image time) spots were observed in 15 active regions in 2K resolution (SN: 378) and 12 active regions in 1K resolution (SN: 234) SDO images on the visible solar disk.

Region 11890 [S12W79] rotated partly out of view.
Region 11893 [S13W11] developed further and could produce C and minor M class flares.
Region 11895 [S20E23] decayed slowly losing spots and penumbral area. There is a weak magnetic delta structure in a central penumbra. M class flares are possible.
Region 11896 [N10E22] was quiet and stable.
Region 11898 [S27W25] decayed slowly and quietly.
Region 11899 [N05E49] has a large main penumbra and has gained several small spots. There is polarity intermixing and a chance of a major flare. The region produced a minor M class flare arly on November 15.
New region 11900 [S20W14] emerged on November 12 and was numbered by SWPC 2 days later. The region developed quickly and has the most significant magnetic delta on the visible disk in a central penumbra. M flares are possible.
New region 11901 [S24W42] emerged on November 10 and got its NOAA number 4 days later.

Spotted regions not numbered by SWPC:
S2828 [S16E38] was quiet and stable.
S2830 [N18E08] developed slowly and quietly.
S2831 [N18W35] was quiet and stable.
New region S2832 [S30W07] emerged with a penumbra spot.
New region S2833 [S10W40] emerged with a penumbra spot.
New region S2834 [N10E42] emerged with a penumbra spot.
New region S2835 [N01E33] emerged with a penumbra spot.

There is a significant chance that November will become the month with the highest solar flux average recorded during cycle 24, two weeks into the month the average SF is higher than that of November 2011.

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

A coronal hole (CH594) in the northern hemisphere was in an Earth facing position on November 12-13.

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

Forecast

The geomagnetic field is expected to be quiet to active on November 15-16 due to effects from CH594. Quiet conditions are likely on November 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 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
11890 2013.11.01
2013.11.02
3 2 1 S12W83 0090 EAO AXX  
11892 2013.11.06       S05W51           plage
11893 2013.11.07
2013.11.08
22 35 19 S13W10 0240 DSI DSC

beta-gamma

area: 0380

S2816 2013.11.07       S19W53         plage
11898 2013.11.08
2013.11.11
5 5 2 S26W25 0010 BXO BXO  
S2820 2013.11.08       N21W59           plage
11895 2013.11.09
2013.11.10
2 87 48 S17E10 0160 HAX FSC beta-gamma-delta

area: 0500

location: S20E23

includes AR 11897

11896 2013.11.10 2 4 2 N11E20 0160 HAX CSO location: N10E22

area: 0260

11901 2013.11.10
2013.11.14
3 12 6 S24W43 0010 BXO DRO area: 0040
11897 2013.11.11 87     S21E26 0310 FKC       magnetically part of 11895
11899 2013.11.12 10 32 14 N07E50 0630 DKI DKO

area: 0900

S2828 2013.11.12   3 2 S16E38 0010   BXO  
11900 2013.11.12
2013.11.14
10 31 14 S19W17 0030 DSO DAC beta-gamma-delta

area: 0150

S2830 2013.11.13   11 4 N18E08 0025   BXO  
S2831 2013.11.13   2 1 N18W35 0007   BXO  
S2832 2013.11.14   1   S30W07 0004   AXX    
S2833 2013.11.14   1 1 S10W40 0004   AXX    
S2834 2013.11.14   1   N10E42 0002   AXX    
S2835 2013.11.14   1   N01E33 0003   AXX    
Total spot count: 144 228 114  
Sunspot number: 234 378 234  (total spot count + 10 * number of spotted regions)
Weighted SN: 189 261 147  (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): 140 132 129 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)
possibe 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) 7.71
2013.11  153.9 (1) 63.7 (2A) / 136.4 (2B) / 89.4 (2C) (56.6 projected, -2.1) (6.5)

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.