Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 18, 2014 at 06:45 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 17. Solar wind speed at SOHO ranged between 331 and 382 km/s.

Solar flux at 20h UTC on 2.8 GHz was 128.8 (decreasing 15.4 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: 2.6). Three hour interval K indices: 00001112 (planetary), 00002211 (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 17 active regions in 2K resolution (SN: 228) and 13 active regions in 1K resolution (SN: 166) SDO images on the visible solar disk.

Region 11948 [N06W79] decayed slowly and quietly.
Region 11949 [S16W45] was quiet and stable.
Region 11950 [N15W58] decayed and lost the leading spot.
Region 11952 [S32W02] was quiet and stable.
Region 11953 [S18W64] decayed slowly and was mostly quiet.
Region 11954 [N07W38] developed slowly and quietly.
Region 11955 [S13E49] was quiet and stable.
New region 11956 [S14E37] rotated into view on January 14 was numbered by SWPC 3 days later.
New region 11957 [N12E49] emerged quickly with several spots.
New region 11958 [S08E78] rotated into view.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3011 [S16W27] decayed slowly and quietly.
S3012 [N08W33] reemerged with a penumbra spot.
New region S3031 [S37E44] emerged at a relatively high latitude with penumbra spots.
New region S3032 [S17E23] emerged with penumbra spots.
New region S3033 [S24E84] rotated partly into view. This region has been very active producing most of the flare activity observed during the day. M class flaring is possible.
C5+ flares: C6.0 at 09:23, C7.2 at 14:03, C8.9 at 16:08 and a long duration C7.1 event peaking at 20:07 UTC.
New region S3034 [S16E88] rotated partly into view.
New region S3035 [S32W30] emerged with a penumbra spot.

Coronal mass ejections (CMEs)

January 15-17: 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

No obvious coronal holes are currently in Earth facing positions. A northern hemisphere coronal hole is likely too far to the north to cause geomagnetic effects.

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 18-20.

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
11948 2014.01.05
2014.01.06
1 2 2 N06W81 0040 HAX AXX area: 0020
11949 2014.01.07
2014.01.08
2 5 4 S17W46 0100 HAX CSO area: 0170
11954 2014.01.08
2014.01.14
  7 3 N07W45 0025   CRO location: N07W38
11951 2014.01.09
2014.01.10
      S12W84           plage
11953 2014.01.09
2014.01.11
3 3 3 S17W66 0040 CAO CRO  
11950 2014.01.09
2014.01.10
  1   N16W65 0002   AXX location: N15W58
11952 2014.01.10
2014.01.11
3 10 5 S33W01 0060 CSO CSO

location: S32W02

S3009 2014.01.10       N10W59           plage
S3011 2014.01.11   2   S16W27 0004   BXO  
S3012 2014.01.12   1 1 N08W33 0004   AXX    
S3014 2014.01.12       S07W59         plage
S3017 2014.01.13       S30W07           plage
11956 2014.01.14
2014.01.17
2 5 3 S15E37 0010 AXX BXO  
S3022 2014.01.14       S13W13           plage
S3023 2014.01.14       S26W54           plage
S3024 2014.01.14       N15W08           plage
11955 2014.01.15
2014.01.16
1 4 2 S15E42 0070 HSX CSO area: 0140

location: S13E49

S3027 2014.01.15       S27W15           plage
S3028 2014.01.15       N22W12           plage
S3029 2014.01.16       S22E64         plage
11957 2014.01.17 2 9 7 N12E48 0030 CRO DAO   area: 0100
11958 2014.01.17 1 1 1 S07E77 0010 HAX HAX   area: 0085

location: S08E78

S3031 2014.01.17   3 2 S37E44 0012   BXO    
S3032 2014.01.17   2 2 S14E37 0007   BXO    
S3033 2014.01.17   1 1 S24E84 0230   HAX    
S3034 2014.01.17   1   S16E88 0300   HHX    
S3035 2014.01.17   1   S32E30 0002   AXX    
Total spot count: 15 58 36  
Sunspot number: 95 228 166  (total spot count + 10 * number of spotted regions)
Weighted SN: 48 104 82  (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): 57 80 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
2014.01 168.7 (1) 76.3 (2A) / 139.1 (2B) / 99.2 (2C) (67.6 projected, +0.2) (6.4)

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.