Solar Terrestrial Activity Report

Last major update issued on November 14, 2010 at 06:15 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)
[Solar cycles 21-24 (last update November 14, 2010)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update November 14, 2010)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update November 14, 2010)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports from January 2003 (last update October 9, 2010)]

[POES auroral activity level charts since October 2009]

Recent activity

The geomagnetic field was quiet to unsettled on November 13. Solar wind speed ranged between 430 and 525 km/s under the influence of a high speed coronal hole stream.

Solar flux measured at 20h UTC on 2.8 GHz was 85.4 (up 1.8 over the last solar rotation). The planetary A index  was 8 (STAR Ap - based on the mean of three hour interval ap indices: 7.8). Three hour interval K indices: 20112233 (planetary), 21122112 (Boulder).

The background x-ray flux is at the class A9 level.

At midnight UTC the visible solar disk had 5 spotted regions.

Region 11123 decayed quickly and is without penumbra on both polarities. Flares: C1.3 at 11:39 and C1.1 at 00:01 (peak on November 14, flare began at 23:50) UTC.
Region 11124 added several spots and remained mostly quiet. C flares are possible.
Region 11125 developed slowly and was quiet.
Region 11126 was quiet and stable.

Spotted regions not numbered by NOAA/SWPC:
[S837] This region emerged late on November 13 near the northwest limb. Location at midnight: N15W75

Coronal mass ejections (CMEs)

November 11 and 13: No obviously Earth directed CMEs were seen in LASCO or STEREO images.
November 12: A partial halo CME was observed over the southern hemisphere following a filament eruption beginning at 16h UTC (the eruption was probably triggered by a C4.6 flare in region 11123). The CME was unimpressive and it is uncertain if it will reach Earth at all.

Coronal holes

Coronal hole history (since late 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 (CH427) was in an Earth facing position on November 11-12.

Image courtesy of SDO (NASA) and the AIA consortium. Annotations are my own. The darkest areas on the solar disk are likely coronal holes.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is fair.

Forecast

The geomagnetic field is expected to be quiet to unsettled on November 14-16 with a chance of active intervals due to effects from CH427.

Coronal holes (1) Coronal mass ejections (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 (Recent map)

Compare to the previous day's image

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 Spot count Location at midnight Area Classification SDO (NASA) / AIA 4500
image
Comment
SWPC STAR SWPC STAR Current Previous
11121 2010.11.04     S23W54           plage
11123 2010.11.10 7 11 S23W24 0050 CRO BXO area: 0020
11124 2010.11.10 11 16 N14W03 0080 DSI CAI area: 0130
S835 2010.11.10     N18W12           plage
11125 2010.11.11 3 5 N19E08 0030 CRO CRO  
11126 2010.11.12 2 3 S30E59 0020 CRO CSO area: 0030
S837 2010.11.13   1 N15W75 0000   AXX    
Total spot count: 23 36  
SSN: 63 86  

Monthly solar cycle data

Month Average measured solar flux International sunspot number (SIDC) Smoothed sunspot number Average ap
(3)
2000.04 184.2 125.5 120.8
cycle 23 sunspot max.
 
2000.07 202.3 170.1 119.8  
2001.12 235.1 132.2 114.6 (-0.9)  
2008.07 65.7 (SF minimum) 0.5 2.8 (-0.4)  
2008.12 69.2 0.8 1.7 (-)
sunspot minimum
3.25
2009.08 67.3 0.0 4.8 (+1.2) 5.70 / 4.89
2009.09 70.5 4.3 6.2 (+1.4) 3.88 / 3.61
2009.10 72.6 4.8 7.1 (+0.9) 3.66 / 3.56
2009.11 73.6 4.1 7.6 (+0.5) 2.45 / 2.63
2009.12 76.7 10.8 8.3 (+0.7) 1.41 / 1.92
2010.01 81.1 13.2 9.3 (+1.0) 2.93 / 3.07
2010.02 84.7 18.8 10.6 (+1.3) 4.15 / 4.61
2010.03 83.4 15.4 12.3 (+1.7) 4.58 / 4.65
2010.04 75.9 8.0 14.0 (+1.7) 10.22 / 10.24
2010.05 73.8 8.7 (15.7 predicted, +1.7) 9.18 / 8.15
2010.06 72.5 13.6 (17.5 predicted, +1.8) 8.17 / 6.85
2010.07 79.8 16.1 (19.1 predicted, +1.6) 6.31 / 5.15
2010.08 79.2 19.6 (20.3 predicted, +1.2) 8.49 / 7.77
2010.09 81.1 25.2 (21.6 predicted, +1.3) 5.33
2010.10 81.6 23.5 (23.9 predicted, +2.3) 6.07
2010.11 83.2 (1) 17.0 (2A) / 39.2 (2B) (26.8 predicted, +3.0) (4.71)

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 international sunspot number is typically 30-50% lower. 2B) Month average to date.
3) Running average based on the daily SWPC ap indices. Values in red are based on the official NGDC ap indices.

This report has been prepared by Jan Alvestad. It is based on 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.