Solar Terrestrial Activity Report

Activity chart

Last major update issued on November 18, 2015 at 04:15 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 to unsettled on November 17. Solar wind speed at SOHO ranged between 345 and 355 km/s.

Solar flux at 20h UTC on 2.8 GHz was 107.1 (decreasing 21.9 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 105.2. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.5). Three hour interval K indices: 23111221 (planetary), 23221322 (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 7 active regions using 2K resolution (SN: 128) and 6 active regions using 1K resolution (SN: 88) SDO images on the visible solar disk.

Region 12452 [S11W32] was quiet and stable.
Region 12454 [N05E13] developed quickly during the first half of the day gaining spots and penumbral area.
Region 12455 [N17W02] decayed slowly and quietly and could soon become spotless.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4884 [S19W28] reemerged with tiny spots.
S4899 [S19E34] gained tiny trailing spots in an old plage area extending over about 50 degrees longitude.
S4902 [N11E17] was quiet and stable.
New region S4904 [N24W12] was observed 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 17: No obviously Earth directed CMEs were observed in available LASCO imagery.
November 15-16: Extensive filament eruptions, mainly in the southwest quadrant were observed late on November 15 and early on November 16. A CME was observed at the southwest limb before midnight on November 15. Components of this CME may be Earth directed and could reach Earth on November 18.

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 recurrent northern hemisphere coronal hole (CH700) was in an Earth facing position on November 14-16.

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.

Forecast

The geomagnetic field is expected to be quiet to active on November 18-19 due to effects from CH700. If the CME observed on November 15-16 reaches Earth on November 18 unsettled to minor storm conditions will be possible, maybe even with major storm intervals. Quiet to unsettled is likely on November 20.

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
12449 2015.11.06       S10W78          
12450 2015.11.06
2015.11.07
      S22W80          

 

S4881 2015.11.09       S08W55            
12452 2015.11.10
2015.11.11
  4   S08W42 0010   BXO location: S11W32
S4884 2015.11.10   2 1 S19W18 0007   BXO    
12453 2015.11.12
2015.11.13
      N06W50          
12454 2015.11.12
2015.11.13
11 19 14 N05E12 0030 DRO DRI area: 0100
S4893 2015.11.12       N04W24            
12455 2015.11.13
2015.11.14
2 1 1 N15W04 0010 BXO AXX

location: N17W02

S4895 2015.11.14       N18W41            
S4897 2015.11.14       S31W49            
S4899 2015.11.15   13 2 S19E34 0025   BXO images/AR_S4899_20151117_2345.png  
S4900 2015.11.15       N24W23          
S4901 2015.11.15       S25W15          
S4902 2015.11.16   16 9 N11E17 0035   BXO  
S4904 2015.11.17   3 1 N24W12 0007   AXX    
Total spot count: 13 58 28  
Sunspot number: 33 128 88  (total spot count + 10 * number of spotted regions)
Weighted SN: 16 61 31  (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): 36 70 75 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 (110.3)   38.1 (2A) / 67.2 (2B) / 91.6 (2C) (65.0 projected, -2.1) (16.9)

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.