Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 22, 2014 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 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 to unsettled on January 21. Solar wind speed at SOHO ranged between 293 and 443 km/s under the influence of effects from CH600.

Solar flux at 20h UTC on 2.8 GHz was 146.0 (increasing 23.3 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 148.0. The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.9). Three hour interval K indices: 31222221 (planetary), 21222332 (Boulder).

The background x-ray flux is at the class B5 level.

At the time of counting spots (see image time) spots were observed in 16 active regions in 2K resolution (SN: 301) and 15 active regions in 1K resolution (SN: 229) SDO images on the visible solar disk.

Region 11952 [S32W52] was quiet and stable.
Region 11955 [S13W03] was quiet and stable.
Region 11957 [N12W06] developed with new flux emerging. The region has polarity intermixing. C and minor M class flares are possible.
Region 11958 [S08E23] decayed slowly and quietly.
Region 11959 [S23E33] was mostly quiet and stable, however, there is a chance of C and minor M class flaring.
Region 11960 [S15E37] gained trailing penumbra spots and was quiet.
Region 11961 [S12W48] decayed slowly and quietly.
New region 11963 [S07E58] rotated into view on January 19 and was numbered by SWPC 2 days later.
New region 11964 [S13E52] emerged on January 20 and was numbered the next day by SWPC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3029 [S25E17] reemerged with penumbra spots.
S3038 [N00E32] decayed early in the day, then developed again during the latter half of the day.
S3039 [S19E07] was quiet and stable.
S3052 [S15E73] was quiet and stable.
S3053 [S08W07] was quiet and stable.
New region S3054 [S20E48] emerged with penumbra spots.
New region S3055 [N14E70] emerged near the northeast limb.

Coronal mass ejections (CMEs)

January 19 and 21: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
January 20: An asymmetric halo CME was observed late in the day after a long duration C3 event involving AR 11963 and a filament eruption.

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 northern hemisphere coronal hole (CH600) rotated across the central meridian on January 18.

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 fair to good.

Forecast

The geomagnetic field is expected to be quiet to unsettled on January 22 due to weak effects from CH600 and quiet on January 23. On January 24 there is a chance of weak effects (unsettled intervals) from the CME observed late on January 20 and early on January 21.

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
11952 2014.01.10
2014.01.11
1 3 1 S32W52 0050 HSX CSO

 

S3017 2014.01.13       S30W59           plage
11956 2014.01.14
2014.01.17
      S15W20           plage
11955 2014.01.15
2014.01.16
2 8 5 S14W04 0050 HAX CAO area: 0100
S3029 2014.01.16   6 2 S25E17 0015   AXX    
11957 2014.01.17 12 34 22 N11W06 0060 DAI DRI beta-gamma

area: 0130

11958 2014.01.17 4 2 2 S08E22 0050 CSO HAX area: 0090
11962 2014.01.17
2014.01.20
      S37W09         plage
S3032 2014.01.17       S14W15           plage
11959 2014.01.17
2014.01.18
14 28 14 S24E33 0220 EAI EHI beta-gamma

area: 0410

11960 2014.01.17
2014.01.18
2 5 3 S15E37 0260 HKX CHO area: 0460
S3035 2014.01.17       S32W22           plage
S3036 2014.01.18       N10W16         plage
S3038 2014.01.18   3 2 N00E32 0017   BXO  
S3039 2014.01.18   6 3 S19E07 0015   BXO  
S3040 2014.01.18       S18E26           plage
S3041 2014.01.18       S06W43           plage
S3043 2014.01.19       S15W28           plage
11963 2014.01.19
2014.01.21
4 18 7 S06E56 0060 CSO CAI  
11961 2014.01.19
2014.01.20
10 16 11 S12W48 0060 DAO DAI area: 0130
S3046 2014.01.19       S38W35           plage
S3047 2014.01.19       N19W54           plage
S3048 2014.01.20       N07E30         plage
S3049 2014.01.20       S10E09         plage
S3050 2014.01.20       S09W23         plage
11964 2014.01.20
2014.01.21
2 5 4 S13E52 0010 BXO CRO area: 0030
S3052 2014.01.20   1 1 S15E73 0070   HSX  
S3053 2014.01.20   2 1 S08W07 0008   BXO  
S3054 2014.01.21   3   S20E48 0005   BXO    
S3055 2014.01.21   1 1 N14E70 0010   HRX    
Total spot count: 51 141 79  
Sunspot number: 141 301 229  (total spot count + 10 * number of spotted regions)
Weighted SN: 96 200 130  (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): 85 105 126 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
2014.01 162.3 (1) 91.3 (2A) / 134.8 (2B) / 102.3 (2C) (67.6 projected, +0.2) (5.7)

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.