Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 25, 2016 at 04:25 UT. The active region section to be updated.

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 (January 1, 2016)
Solar cycle Solar cycles 23-24 (January 1, 2016) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (January 1, 2016) 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 (January 1, 2016) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12, 13, 14, 16 and 24 (January 1, 2016) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (December 27, 2015)  

Recent activity

The geomagnetic field was quiet to active on January 24. Solar wind speed at SOHO ranged between 389 and 470 km/s. The single active interval was related to a brief southward swing of the Bz component of the IMF.

Solar flux at 20h UTC on 2.8 GHz was 103.8 (decreasing 8.3 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 105.8. The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.9). Three hour interval K indices: 32211241 (planetary), 22112342 (Boulder).

The background x-ray flux is at the class B2 level.

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 207) and 7 active regions using 1K resolution (SN: 112) SDO images on the visible solar disk.

Region 12486 [S25W10] was quiet and stable.
Region 12487 [S12W18] decayed slowly and quietly.
Region 12488 [N02W01] gained spots and penumbral area after noon. The region has weak polarity intermixing.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5039 [N03W27] was quiet and stable.
New region S5050 [S19E80] rotated into view with small spots.
New region S5051 [N10E69] emerged with several spots near the northeast limb.
New region S5052 [N06E28] emerged with a tiny spot.
New region S5053 [N26E13] emerged near the southern edge of CH711 with tiny spots.
New region S5054 [N07W74] emerged with tiny spots.
New region S5055 [N17W36] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location AR Recorded by Comment
           

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

Coronal mass ejections (CMEs)

January 22-24: 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 recurrent northern hemisphere coronal hole (CH711) will likely rotate into an Earth facing position on January 25-26.

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 mostly quiet on January 25-27. On January 28-29 there is a chance of unsettled to active conditions due to effects from CH711.

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). 4K resolution. Compare to the previous day's image.
As of December 12, 2015, the active region maps are based on image products from semi-automated sunspot counting at 4K resolution.

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
12485 2016.01.13
2016.01.14
      N15W60          
12486 2016.01.16
2016.01.17
1 16 2 S19W09 0010 HRX BXO images/AR_12486_20160123_2345.png images/AR_12486_20160122_2345.png  
12487 2016.01.18
2016.01.19
10 23 11 S12W05 0040 CAO CRI

area: 0080

S5039 2016.01.18   14 2 N03W09 0025   BXO images/AR_S5039_20160123_2345.png images/AR_S5039_20160122_2345.png  
12488 2016.01.18
2016.01.20
13 29 17 N03E12 0120 DAI DAI area: 0210
S5042 2016.01.18   1   N14W47 0003   AXX  
S5045 2016.01.20       S04W07            
S5047 2016.01.21   2   N19W09 0004   AXX  
S5048 2016.01.21   2   S28E25 0002   BXO    
S5049 2016.01.21   1   S18W18 0001   AXX    
Total spot count: 24 88 32  
Sunspot number: 54 168 72  (total spot count + 10 * number of spotted regions)
Weighted SN: 37 96 40  (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): 59 92 61 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
2014.11 154.8 151.4 103.6 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 78.8 (-3.4) 10.73
2015.05 120.0 122.6 88.8 76.0 (-2.8) 8.29
2015.06 122.3 126.1 66.5 72.0 (-4.0) 13.15
2015.07 107.0 110.8 66.4 (68.3 projected, -3.7) 8.83
2015.08 105.4 108.0 64.6 (66.3 projected, -2.0) 14.58
2015.09 101.7 102.7 78.1 (66.3 projected, +0.0) 15.78
2015.10 104.1 103.3 61.7 (65.9 projected, -0.4) 14.02
2015.11 109.3 106.9 63.2 (63.8 projected, -2.1) 12.09
2015.12 113.1 109.5 57.7 (62.1 projected, -1.7) 14.29
2016.01 (102.0)   38.3 (2A) / 49.6 (2B) / 65.3 (2C) (60.4 projected, -1.7) (11.8)

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.