Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 30, 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 on January 29. Solar wind speed at SOHO ranged between 360 and 473 km/s under the influence of weak effects from CH601.

Solar flux at 20h UTC on 2.8 GHz was 156.4 (decreasing 4.1 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 146.6. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.8). Three hour interval K indices: 22211212 (planetary), 22222222 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time) spots were observed in 12 active regions in 2K resolution (SN: 223) and 9 active regions in 1K resolution (SN: 148) SDO images on the visible solar disk.

Region 11959 [S23W75] decayed slowly and quietly.
Region 11960 [S15W69] was quiet and stable
.
Region 11963 [S09W43] decayed slowly and quietly.
Region 11964 [S19W48] was quiet and stable.
Region 11965 [S14W27] decayed slowly and quietly.
Region 11967 [S12E59] has multiple magnetic delta structures within the largest spot complex. A major flare is possible.
C5+ flares: C7.3 at 04:31, long duration C7.0 peaking at 15:31 UTC.
Region 11968 [N10E56] appears to be in slow decay. Further C class flaring is possible.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3071 [S09E08] developed slowly and quietly
S3072 [S15W42] was quiet and stable. (SWPC has this as AR 11965)
New region S3074 [S17W09] emerged with a penumbra spot.
New region S3075 [S12E82] rotated into view with a penumbra spot.
New region S3076 [N13E03] emerged with a penumbra spot.

A filament eruption late on January 28 and early on January 29 in the southwest quadrant was the source of an asymmetric halo CME. The CME was best defined over the southwest and southern parts.

Coronal mass ejections (CMEs)

January 27-28: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
January 29: A halo CME was observed after a filament eruption in the southwest quadrant. While the core of the CME will not reach Earth, there's a chance a weak solar wind shock will be observed on February 1.

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) was in an Earth facing position on January 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 fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet on January 30-31. On February 1 there's a chance of a few unsettled intervals due to weak CME effects.

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
11958 2014.01.17       S08W87           plage
11959 2014.01.17
2014.01.18
1 1 1 S23W75 0090 HAX HAX

area: 0170

11960 2014.01.17
2014.01.18
3 5 3 S15W70 0070 HSX CAO  

area: 0160

11963 2014.01.19
2014.01.21
  3 1 S18W54 0009   AXX SWPC location on Jan.27: S06W25

location: S09W43

11964 2014.01.20
2014.01.21
  3 1 S09W49 0010   AXX SWPC location on Jan.27: S14W28

location: S19W48

11965 2014.01.20
2014.01.22
2 5 2 S13W43 0020 CRO BXO SWPC location on Jan.28: S14W24

location: S14W27

area: 0010

S3054 2014.01.21       S20W55           plage
S3055 2014.01.21       N15W33           plage
S3057 2014.01.22       N05W16           plage
S3060 2014.01.24       S01W33           plage
S3061 2014.01.24       N08W40           plage
S3062 2014.01.24       S28W40           plage
11966 2014.01.25       S12W29           merged with AR 11965
S3064 2014.01.26       N22W12           plage
S3065 2014.01.26       S13W59         plage
11967 2014.01.26
2014.01.27
29 60 36 S14E55 0980 FKC FKC beta-gamma-delta

area: 1910

location: S12E59

 

11968 2014.01.27 11 15 8 N09E54 0210 EAO EAO location: N10E56

area: 0250

S3070 2014.01.28       N13E15         plage
S3071 2014.01.28   3 3 S09E08 0014   BXO  
S3072 2014.01.28   5 3 S15W42 0020   BXO SWPC has moved AR 11965 to this location
S3073 2014.01.28       N20E60         plage
S3074 2014.01.29   1   S17W09 0003   AXX    
S3075 2014.01.29   1   S12E82 0006   AXX    
S3076 2014.01.29   1   N13E03 0003   AXX    
Total spot count: 46 103 58  
Sunspot number: 96 223 148  (total spot count + 10 * number of spotted regions)
Weighted SN: 74 128 83  (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): 58 78 81 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
2014.01 157.0 (1) 118.9 (2A) / 127.1 (2B) / 104.0 (2C) (67.6 projected, +0.2) (5.6)

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.