Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 9, 2014 at 05:30 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 December 16, 2013]
[Presentation 3rd SSN Workshop, Tucson, 2013 (pdf)]

Recent activity

The geomagnetic field was quiet to unsettled on January 8. Solar wind speed at SOHO ranged between 295 and 363 km/s.

Solar flux estimated at 20h UTC on 2.8 GHz was 195 (increasing 30.2 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 147.0. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.3). Three hour interval K indices: 33111012 (planetary), 44011221 (Boulder).

The background x-ray flux is at the class B9 level.

At the time of counting spots (see image time) spots were observed in 11 active regions in 2K resolution (SN: 300) and 10 active regions in 1K resolution (SN: 201) SDO images on the visible solar disk.

Region 11942 [N14W36] lost the leader spot and gained a trailing penumbra spot.
Region 11943 [S14W27] decayed slowly and quietly.
Region 11944 [S09W14] decayed further losing in excess of 10% of its penumbral area. While there are several small magnetic delta structures, the flare rate is low. A major flare is possible.

Region 11946 [N09W17] decayed slowly and quietly.
Region 11948 [N06E40] was quiet and stable.
New region 11949 [S15E69] rotated into view on January 7 and was numbered the next day by SWPC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S2995 [S17E18] was quiet and stable.
New region S3001 [N07E80] rotated into view.
New region S3002 [N12E20] emerged with penumbra spots.
New region S3003 [N19E09] emerged with penumbra spots.
New region S3004 [S10W71] emerged with penumbra spots.

Coronal mass ejections (CMEs)

January 6, 8: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
January 7: A full halo CME was observed after the X1 event in AR 11943. Given the exit speed, this CME could reach Earth during the first half of January 9.

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 trans equatorial coronal hole (CH599) will rotate into an Earth facing position on January 9-10.

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 very poor due to high proton levels. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet to major storm, possibly with severe storm intervals, on January 9-10 due to CME effects. Quiet to unsettled is likely on January 11. A high speed stream from CH599 could cause quiet to active conditions on January 12-13.

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
S2971 2013.12.30       S22W58           plage
11943 2013.12.30
2013.12.31
  11 2 S11W35 0020   BXO

location: S14W27

11942 2013.12.30
2013.12.31
  1 1 N10W48 0005   AXX location: N14W36
11944 2013.12.31
2014.01.01
118 124 68 S09W17 1560 FKC FKC beta-gamma-delta

area: 1980

location: S09W14

11945 2014.01.01
2014.01.02
      N11W67           plage
S2983 2014.01.03       N21W00           plage
11946 2014.01.04 18 34 20 N09W21 0290 DKI DKI

location: N09W17

area: 0400

S2988 2014.01.04       N20W31           plage
11948 2014.01.05
2014.01.06
1 3 2 N06E40 0060 HSX HSX area: 0160
S2992 2014.01.05       N17W04           plage
S2993 2014.01.05       N04W31           plage
S2995 2014.01.05   6 2 S17E18 0015   BXO  
S2996 2014.01.06       S01W13           plage
11949 2014.01.07
2014.01.08
1 2 1 S15E70 0080 HSX HHX area: 0290
S2999 2014.01.07       S32W04         plage
S3000 2014.01.07       S19W05         plage
S3001 2014.01.08   1 1 N07E80 0005   HRX    
S3002 2014.01.08   4 3 N12E20 0015   AXX    
S3003 2014.01.08   2   N19E09 0005   BXO    
S3004 2014.01.08   2 1 S10W71 0007   BXO    
Total spot count: 138 190 101  
Sunspot number: 178 300 201  (total spot count + 10 * number of spotted regions)
Weighted SN: 168 228 139  (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): 107 105 111 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
2014.01 191.5 (1) 45.9 (2A) / 177.9 (2B) / 100.3 (2C) (67.6 projected, +0.2) (7.5)

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.