Solar Terrestrial Activity Report

Last major update issued on November 22, 2003 at 04:15 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 4, 2003)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 4, 2003)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 4, 2003)]
[Historical solar and geomagnetic data charts 1954-2003 (last update October 15, 2003)]
[Archived reports (last update November 12, 2003)]

Recent activity

The geomagnetic field was quiet to severe storm on November 21. Solar wind speed ranged between 446 and 581 km/sec.

Solar flux measured at 20h UTC on 2.8 GHz was 177.0. The planetary A index was 39 (STAR Ap - based on the mean of three hour interval ap indices: 39.1).
Three hour interval K indices: 76643332 (planetary), 56543333 (Boulder).

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

At midnight there were 4 spotted regions on the visible disk. Solar flare activity was low. A total of 5 C class events were recorded during the day.

Region 10501 decayed, particularly in the southern spot section. The positive polarity umbra within the predominantly negative polarity northern penumbra moved closer to the negative polarity umbra. This could again increase the possibility of an M class flare.
Region 10506 decayed slowly and quietly. Flare: C4.3 at 09:43 UTC.
Region 10507 was mostly unchanged and quiet. A major flare is possible.
Region 10508 was mostly unchanged, a few small spots emerged. A major flare is still possible. Flares: C1.0 at 02:38, C1.0 at 12:53, C3.4 at 19:16 and C1.1 at 20:43 UTC

Coronal mass ejections (CMEs)

November 20: A faint full halo CME was observed after the M9.6 flare in region 10501, in LASCO C2 images the CME was first visible at 08:06 UTC. This CME could reach the Earth during the latter half of November 22.

November 19 and 21: No partly or fully earth directed CMEs observed.

Coronal holes

Coronal hole history (since late October 2002)
Compare today's report with the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago

A coronal hole (CH68) in the northern hemisphere was in a geoeffective position on November 20-21. A new and developing coronal hole (CH69) in the southern hemisphere will be in a geoeffective position on November 22.

Processed SOHO/EIT 284 image at 01:05 UTC on November 22. The darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet to minor storm on November 22 with a likely impact from the CME observed on November 20 sometime during the day. A fairly weak high speed stream from coronal hole CH68 could influence the geomagnetic field on November 23-24 while another high speed stream from coronal hole CH69 could arrive on November 25. Unsettled to active is expected for November 23-25.

Long distance low frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is very poor to useless. Propagation along long distance north-south paths is poor. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and Radio Rafaela (Argentina). Another station from Argentina was noted at times].

Coronal holes (1) Coronal mass ejections (2) M and X class flares (3)
Coronal hole indicator CME indicator M and X class flare indicator

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) Material from a CME is likely to impact 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/SEC. 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 SEC or where SEC has observed no spots. SEC active region numbers in the table below and in the active region map above are the historic SEC/USAF numbers.

Active region Date numbered SEC
spot
count
STAR
spot
count
Location at midnight Area Classification Comment
10501 2003.11.13 14 12 N04W32 0310 DKI beta-gamma-delta
classification was DKO
at midnight, area 0280
10502 2003.11.14     N07W48     plage
10503 2003.11.15     N17W70     plage
10505 2003.11.17 2   S22E07 0020 AXX spotless
10506 2003.11.18 10 13 S21E32 0060 CAO classification was CAI
at midnight
10507 2003.11.18 28 32 N09E36 0800 EKI beta-gamma
classification was EKC
at midnight
10508 2003.11.19 27 38 S18E47 0510 FAI beta-gamma
classification was EAI
at midnight
Total spot count: 81 95
SSN: 131 135

Monthly solar cycle data

Month Average solar
flux at Earth
International sunspot number Smoothed sunspot number
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)
2002.10 167.0 97.5 90.5 (-4.1)
2002.11 168.7 95.5 85.2 (-5.3)
2002.12 157.2 80.8 82.0 (-3.2)
2003.01 144.0 79.7 80.9 (-1.1)
2003.02 124.5 46.0 78.5 (-2.4)
2003.03 131.4 61.1 74.1 (-4.4)
2003.04 126.4 60.0 70.3 (-3.8)
2003.05 115.7 55.2 (66.8 predicted, -3.5)
2003.06 129.3 77.4 (63.0 predicted, -3.8)
2003.07 127.7 85.0 (59.3 predicted, -3.7)
2003.08 122.1 72.7 (56.3 predicted, -3.0)
2003.09 112.2 48.8 (54.3 predicted, -2.0)
2003.10 151.7 65.6 (51.6 predicted, -2.7)
2003.11 128.1 (1) 51.9 (2) (48.9 predicted, -2.7)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC) sunspot number. The official international sunspot number is typically 30-50% less.

This report has been prepared by Jan Alvestad. It is based partly on my own observations and analysis, and partly on data from sources noted in solar links. All time references are to the UTC day. Comments and suggestions are always welcome.


[DX-Listeners' Club]