Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 23, 2014 at 05:40 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 22. Solar wind speed at SOHO ranged between 408 and 584 km/s under the influence of a high speed stream from CH600.

Solar flux at 20h UTC on 2.8 GHz was 143.3 (increasing 19.6 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 147.8. The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.9). Three hour interval K indices: 22332113 (planetary), 11343322 (Boulder).

The background x-ray flux is at the class B4 level.

At the time of counting spots (see image time) spots were observed in 15 active regions in 2K resolution (SN: 308) and 15 active regions in 1K resolution (SN: 236) SDO images on the visible solar disk.

Region 11952 [S32W64] was quiet and stable.
Region 11955 [S13W18] was quiet and stable.
Region 11957 [N11W20] gained spots and has a weak magnetic delta structure centrally. Although none of the umbrae in the region are impressive, there is a chance of C flares.
Region 11958 [S08E10] decayed slowly and quietly.
Region 11959 [S23E19] matured quietly.
Region 11960 [S15E23] was quiet and stable.
Region 11961 [S12W61] decayed slowly and quietly.
Region 11963 [S08E46] decayed slowly and quietly.
Region 11964 [S13E40] decayed slowly and quietly.
New region 11965 [S15E61] rotated into view on January 20 and was numbered by SWPC 2 days later.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3029 [S24E02] gained several penumbra spots.
S3038 [N00E18] was quiet and stable.
S3039 [S22W08] was quiet and stable.
S3055 [N15E58] was quiet and stable.
New region S3057 [N06E75] emerged near the northeast limb with a penumbra spot.

Coronal mass ejections (CMEs)

January 21-22: 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 small northern hemisphere coronal hole (CH601) will likely rotate into an Earth facing position on Janaury 25.

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 23 due to weak effects from CH600. 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 S31W66 0030 HSX CSO

location: S32W64

11956 2014.01.14
2014.01.17
      S15W34           plage
11955 2014.01.15
2014.01.16
2 11 5 S13W17 0040 CAO DAO area: 0070
S3029 2014.01.16   15 6 S24E02 0030   BXO  
11957 2014.01.17 14 43 24 N11W19 0090 DAI DAC beta-gamma-delta

area: 0220

11958 2014.01.17 2 6 3 S08E09 0030 HAX CSO area: 0050
11962 2014.01.17
2014.01.20
      S37W23           plage
S3032 2014.01.17       S14W28           plage
11959 2014.01.17
2014.01.18
11 31 18 S23E20 0120 EAO EHO beta-gamma

area: 0350

11960 2014.01.17
2014.01.18
2 10 7 S15E22 0270 HKX CHO area: 0510
S3035 2014.01.17       S32W35           plage
S3036 2014.01.18       N10W29           plage
S3038 2014.01.18   4 2 N00E18 0015   BXO  
S3039 2014.01.18   6 4 S22W08 0020   BXO  
S3040 2014.01.18       S18E13           plage
S3041 2014.01.18       S06W56           plage
S3043 2014.01.19       S15W41           plage
11963 2014.01.19
2014.01.21
3 12 5 S06E44 0010 BXO CRO area: 0030
11961 2014.01.19
2014.01.20
5 9 4 S11W62 0050 DSO DAO area: 0080
S3046 2014.01.19       S38W48           plage
S3048 2014.01.20       N07E17           plage
S3049 2014.01.20       S10W04           plage
S3050 2014.01.20       S09W36           plage
11964 2014.01.20
2014.01.21
2 2 2 S13E40 0010 AXX BXO  
11965 2014.01.20
2014.01.22
2 3 3 S15E59 0020 HRX HRX area: 0040
S3053 2014.01.20       S08W20         plage
S3054 2014.01.21       S20E35         plage
S3055 2014.01.21   2 1 N15E58 0010   BXO  
S3057 2014.01.22   1 1 N06E75 0004   AXX    
Total spot count: 44 158 86  
Sunspot number: 144 308 236  (total spot count + 10 * number of spotted regions)
Weighted SN: 87 209 137  (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): 86 108 130 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
2014.01 161.5 (1) 96.0 (2A) / 135.2 (2B) / 103.8 (2C) (67.6 projected, +0.2) (5.9)

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.