Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 15, 2014 at 06:00 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 14. Solar wind speed at SOHO ranged between 560 and 658 km/s under the influence of a high speed stream from CH599.

Solar flux at 20h UTC on 2.8 GHz was 137.0 (decreasing 19.0 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 148.9. The Potsdam WDC planetary A index was 10 (STAR Ap - based on the mean of three hour interval ap indices: 9.8). Three hour interval K indices: 33213212 (planetary), 32124432 (Boulder).

The background x-ray flux is at the class B6 level.

At the time of counting spots (see image time) spots were observed in 15 active regions in 2K resolution (SN: 236) and 14 active regions in 1K resolution (SN: 192) SDO images on the visible solar disk.

Region 11948 [N05W40] was quiet and stable.
Region 11949 [S17W07] was quiet and stable.
Region 11950 [N16W23] developed slowly and quietly.
Region 11952 [S32E37] decayed slowly and quietly.
Region 11953 [S18W24] was quiet and appears to be slowly decaying.
New region 11954 [N07W00] was first observed with spots on January 8 and was numbered by SWPC 6 days later.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3011 [S17E13] was quiet and stable.
S3012 [N10E10] reemerged with a penumbra spot.
S3013 [N10W32] was quiet and stable.
S3014 [S09W13] was quiet and stable.
S3017 [S30E32] decayed slowly and quietly.
New region S3021 [S14E78] rotated into view.
New region S3022 [S13E26] emerged with a penumbra spot.
New region S3023 [S26W15] emerged with a penumbra spot.
New region S3024 [N13E27] emerged with penumbra spots.

A filament eruption was observed in the northeast quadrant after 06:40 UTC. The associated partial halo CME probably does not have Earth directed extensions.

Coronal mass ejections (CMEs)

January 12-14: 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 or near Earth facing positions.

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 to fair.

Forecast

The geomagnetic field is expected to be quiet on January 15-17.

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
11944 2013.12.31
2014.01.01
4     S12W88 0140 DAC    

rotated out of view

11948 2014.01.05
2014.01.06
1 2 2 N06W41 0070 HAX HAX area: 0140
11949 2014.01.07
2014.01.08
2 14 9 S16W08 0110 HAX CAO area: 0280
11954 2014.01.08
2014.01.14
3 7 3 N07W01 0010 BXO BXO  
S3002 2014.01.08       N10W59           plage
11951 2014.01.09
2014.01.10
  1 1 S12W42 0004   AXX  
11953 2014.01.09
2014.01.11
6 22 10 S17W25 0070 DAO DAC area: 0150
11950 2014.01.09
2014.01.10
5 19 11 N17W23 0010 BXO CRO area: 0040
11952 2014.01.10
2014.01.11
4 5 4 S31E35 0070 CSO ESO

location: S32E37

S3009 2014.01.10       N10W20         plage
S3010 2014.01.10       S32W34           plage
S3011 2014.01.11   3 3 S17E13 0018   AXX  
S3012 2014.01.12   1   N10E10 0002   AXX    
S3013 2014.01.12       N10W45         plage
S3014 2014.01.12   4 3 S09W13 0017   BXO  
S3015 2014.01.12       N15W40           plage
S3017 2014.01.13   3 2 S30E32 0012   HRX  
S3018 2014.01.13       N07W29         plage
S3021 2014.01.14   1 1 S14E78 0010   HRX    
S3022 2014.01.14   1 1 S13E26 0008   AXX    
S3023 2014.01.14   1 1 S26W15 0004   AXX    
S3024 2014.01.14   2 1 N13E27 0006   BXO    
Total spot count: 25 86 52  
Sunspot number: 95 236 192  (total spot count + 10 * number of spotted regions)
Weighted SN: 50 115 81  (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 83 106 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
2014.01 178.0 (1) 67.9 (2A) / 150.4 (2B) / 101.8 (2C) (67.6 projected, +0.2) (7.0)

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.