Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 12, 2014 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 January 1, 2014)] [Cycle 24 progress (last update January 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update January 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update January 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update January 1, 2014)]

[POES auroral activity level since October 2009 - updated January 26, 2013]
[Solar polar fields vs solar cycles - updated January 11, 2014]
[Presentation 3rd SSN Workshop, Tucson, 2013 (pdf)]

Recent activity

The geomagnetic field was quiet on January 11. Solar wind speed at SOHO ranged between 349 and 419 km/s.

Solar flux at 20h UTC on 2.8 GHz was 166.1 (increasing 9.9 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 148.4. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 2.9). Three hour interval K indices: 00000022 (planetary), 00111221 (Boulder).

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

At the time of counting spots (see image time) spots were observed in 11 active regions in 2K resolution (SN: 261) and 9 active regions in 1K resolution (SN: 166) SDO images on the visible solar disk.

Region 11944 [S10W54] displayed increasing activity as a new magnetic delta structure formed in the trailing spot section. A major flare is still possible. C5+ flares: C6.5 at 13:10, C6.0 at 00:05 (peak on January 12, flare started on January 11) UTC.
Region 11946 [N08W57] decayed slowly and was mostly quiet.
Region 11948 [N05W00] was quiet and stable.
Region 11949 [S17E31] was quiet and stable.
Region 11950 [N16E18] decayed slowly and quietly.
Region 11951 [S13E01] decayed slowly and quietly.
New region 11952 [S32E75] rotated partly into view on January 10 and was numbered the next day by SWPC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S2995 [S16W26] decayed slowly and quietly.
S3006 [S18E15] developed slowly and quietly.
S3009 [N07E18] was quiet and stable.
New region S3011 [S15E47] was observed with penumbra spots in an old plage area.

Coronal mass ejections (CMEs)

January 9-11: 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 (CH599) was in an Earth facing position on January 9-10.

Coronal hole map

Propagation

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

Forecast

The geomagnetic field is expected to be quiet to active on January 12-13 and quiet to unsettled on January 14 due to effects from CH599.

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
11943 2013.12.30
2013.12.31
      S11W77        

plage

location: S17W66

11944 2013.12.31
2014.01.01
37 68 34 S10W54 1300 FKC FKC beta-gamma-delta

area: 1570

S2983 2014.01.03       N21W39           plage
11946 2014.01.04 15 29 11 N10W58 0190 EAI EAI

location: N08W57

11948 2014.01.05
2014.01.06
1 13 7 N06W02 0080 HSX CSO area: 0160
S2992 2014.01.05       N17W43           plage
S2995 2014.01.05   4 3 S16W26 0015   BXO images/AR_S2995_20140110_2345.png  
S2996 2014.01.06       S01W52           plage
11949 2014.01.07
2014.01.08
3 5 2 S15E30 0140 HSX CAO area: 0230

location: S17E31

S2999 2014.01.07       S32W43           plage
S3000 2014.01.07       S19W44           plage
S3001 2014.01.08       N07E40     AXX   plage
S3002 2014.01.08       N10W20         plage
S3003 2014.01.08       N19W30           plage
11951 2014.01.09
2014.01.10
2 4 3 S12W02 0020 CRO CRO location: S13E01
S3006 2014.01.09   8 5 S18E15 0040   DRO  
11950 2014.01.09
2014.01.10
5 10 6 N16E18 0030 DRO CRO area: 0070
11952 2014.01.10
2014.01.11
1 7 5 S33E75 0040 HAX DSO area: 0200
S3009 2014.01.10   1   N07E18 0003   AXX  
S3010 2014.01.10       S32E05         plage
S3011 2014.01.11   2   S15E47 0003   AXX    
Total spot count: 64 151 76  
Sunspot number: 134 261 166  (total spot count + 10 * number of spotted regions)
Weighted SN: 100 190 115  (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 91 91 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)
possible cycle 24 max
8.81
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 59.9 (+2.0) 9.73
2013.06 110.1 52.5 62.6 (+2.7) 12.60
2013.07 115.5 57.0 (65.4 projected, +2.8) 9.47
2013.08 114.6 66.0 (67.8 projected, +2.4) 8.27
2013.09 102.6 36.9 (70.1 projected, +2.3) 5.23
2013.10  132.1 85.6 (70.0 projected, -0.1) 7.71
2013.11  148.3 77.6 (68.1 projected, -1.9) 5.68
2013.12 147.7 90.3 (67.4 projected, -0.7) 4.68
2014.01 187.0 (1) 57.8 (2A) / 162.8 (2B) / 100.5 (2C) (67.6 projected, +0.2) (6.7)

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.