Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 21, 2015 at 07:40 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data from 2003.01 (November 1, 2015)
Solar cycle Solar cycles 23-24 (November 1, 2015) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (November 1, 2015) Noon SDO sunspot count 1K Reference: 4K (large file) (*)
  Solar cycles 1-24 (July 17, 2015) POES auroral activity level October 2009 - December 2012
  Comparison of cycles 21, 22, 23 and 24 (November 1, 2015) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12, 13, 14, 16 and 24 (November 1, 2015) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (November 16, 2015)  

Recent activity

The geomagnetic field was quiet on November 20. Solar wind speed at SOHO ranged between 346 and 500 km/s.

Solar flux at 20h UTC on 2.8 GHz was 111.0 (increasing 4.7 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 105.0. The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 3.5). Three hour interval K indices: 11221001 (planetary), 12321211 (Boulder).

The background x-ray flux is at the class B3 level.

At the time of counting spots (see image time), spots were observed in 8 active regions using 2K resolution (SN: 149) and 7 active regions using 1K resolution (SN: 101) SDO images on the visible solar disk.

Region 12454 [N06W28] was quiet and stable. This is AR 12456 to SWPC.
Region 12457 [N11E64] was quiet, however, the region has polarity intermixing and C class flaring is likely.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4899 [S16W20] decayed losing the trailing spots.
S4902 [N12W27] developed during the latter half of the day. This is AR 12454 to SWPC.
S4906 [N14E21] was quiet and stable.
New region S4911 [S03W35] emerged early in the day, the positive polarity leader spot disappeared after noon.
New region S4912 [N22E79] rotated into view.
New region S4913 [S04W48] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UTC) Location AR Recorded by Comment
           

Flare activity (SDO/EVE/ESP XRS-B proxy)

Coronal mass ejections (CMEs)

November 18-20: No obviously Earth directed CMEs were observed in available LASCO 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]

A northern hemisphere coronal hole (CH701) will likely rotate into an Earth facing position on November 21-22, CH701 may be too far to the north to become geoeffective.

Propagation

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

Forecast

The geomagnetic field is expected to be quiet on November 21-23. There is a minor possibility of a weak disturbance on November 24-25 due to effects from CH701.

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: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% 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 overlays
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12452 2015.11.10
2015.11.11
      S08W84         images/AR_12452_20151119_2345.png  
S4884 2015.11.10       S19W57            
12454 2015.11.12
2015.11.13
6 16 6 N12W28 0020 CRO DRI area: 0050

location: N06W28

SWPC has renumbered this as AR 12456

12455 2015.11.13
2015.11.14
      N15W46        

 

S4899 2015.11.15   4 1 S16W20 0008   AXX images/AR_S4899_20151120_2345.png images/AR_S4899_20151119_2345.png  
S4901 2015.11.15       S25W54            
S4902 2015.11.16   21 11 N12W27 0060   DRI images/AR_S4902_20151120_2345.png images/AR_S4902_20151119_2345.png this is AR 12454 to SWPC
S4904 2015.11.17       N25W51          
12456 2015.11.18 8     N06W29 0020 DRO       see AR 12454 and AR S4902
12457 2015.11.18
2015.11.19
8 21 10 N11E63 0110 DSO DAC beta-gamma

area: 0280

S4906 2015.11.19   2 1 N14E21 0005   BXO  
S4907 2015.11.19       N19E28          
S4908 2015.11.19       S22E06          
S4910 2015.11.19       N03W13          
S4911 2015.11.20   2 1 S03W35 0005   AXX    
S4912 2015.11.20   1 1 N22E79 0005   AXX    
S4913 2015.11.20   2   S04W48 0005   BXO    
Total spot count: 22 69 31  
Sunspot number: 52 149 101  (total spot count + 10 * number of spotted regions)
Weighted SN: 33 80 42  (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 82 86 k * (sunspot number)
As of July 1, 2015: k = 1.1 for SWPC, k = 0.55 for MSN 2K, k = 0.85 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO) (4)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (cycle peak) 110.5 (+1.2) 10.70
2014.04 143.9 144.8 112.5 116.4 (+2.1) (solar max) 7.88
2014.09 146.6 148.1 130.0 101.9 (-6.4) 9.78
2014.10 153.4 152.9 90.0 97.3 (-4.6) 8.96
2014.11 154.8 151.4 103.6 94.7 (-2.6) 9.33
2014.12 158.7 153.8 112.9 92.2 (-2.5) 11.24
2015.01 141.9 137.3 93.0 89.3 (-2.9) 9.46
2015.02 129.1 126.0 66.7 86.1 (-3.2) 9.92
2015.03 125.9 124.6 54.5 82.2 (-3.9) 16.14
2015.04 128.8 129.7 75.3 78.9 (-3.3) 10.73
2015.05 120.0 122.6 88.8 (76.3 projected, -2.6) 8.29
2015.06 122.3 126.1 66.5 (72.6 projected, -3.7) 13.15
2015.07 107.0 110.8 66.4 (68.9 projected, -3.7) 8.83
2015.08 105.4 108.0 64.6 (67.7 projected, -1.2) 14.58
2015.09 101.7 102.7 78.1 (68.0 projected, +0.3) 15.78
2015.10 104.1 103.3 61.7 (67.1 projected, -0.9) 14.02
2015.11 (110.1)   42.7 (2A) / 64.1 (2B) / 89.8 (2C) (65.0 projected, -2.1) (15.6)

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).
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 GFZ Potsdam WDC ap indices.
4) Updated to new data set from WDC-SILSO on July 1, 2015

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 Universal Time. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.