Solar Terrestrial Activity Report

Activity chart

Last major update issued on August 18, 2022 at 03:50 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data since 2003.01 (August 7, 2022)
Solar cycle Solar cycles 23-25 (August 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (August 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (July 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (August 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (August 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (April 10, 2022) Cycle 25 spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing Research: Solar Cycle 25 Started on November 17, 2019 with 365 Days Smoothing

Recent activity

The geomagnetic field was quiet to major storm on August 17 under the influence of a high speed stream from CH1094. Solar wind speed at SOHO ranged between 355 and 588 km/sec. The high latitude magnetometer at Andenes recorded quiet to major storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 122.7 - increasing 1.0 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 108.70). The Potsdam WDC planetary A index was 30 (STAR Ap - based on the mean of three hour interval ap indices: 29.9). Three hour interval K indices: 23123466 (planetary), 23233444 (Boulder), 42123465 (Andenes).

The background x-ray flux is at the class B5 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 269) and in 10 active regions using 1K resolution (SN: 168) SDO/HMI images.

Region 13076 [N15W60] decayed slowly and quietly.
Region 13078 [S23W32] became less compact as the main penumbral area expanded and split into smaller penumbrae. The region still has several magnetic delta structures and could produce another major flare. C1 flares: C1.6 @ 01:42, C1.5 @ 02:32, C1.1 @ 05:37, C1.1 @ 18:24 UT
Region 13079 [S11W78] decayed significantly losing all penumbra and a large number of spots.
Region 13081 [N10W11] decayed slowly and was mostly quiet. C1 flare: C1.0 @ 21:11, C1.3 @ 21:22 UT
Region 13082 [N27E37] developed early in the day and decayed after noon. C1 flares: C1.2 @ 13:24, C1.5 @ 16:14, C1.4 @ 17:31, C1.3 @ 20:41 UT
Region 13083 [S25W43] decayed slowly and was mostly quiet.

Spotted regions not observed (or interpreted differently) by SWPC:
S7776 [N21W62] decayed further and was quiet.
S7778 [S10E35] was quiet and stable.
S7786 [S19E59] decayed slowly and quietly.
S7787 [N35W02] decayed slowly and quietly.
S7789 [N13W25] was quiet and stable.
New region S7790 [N12E32] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.8 04:57 S24W17 13078 GOES16  
C3.3 07:10 N28E47 13082 GOES16  
C9.0 08:20 S22W26 13078 GOES16  
C4.0 09:36 N29E46 13082 GOES16  
C4.3 11:31 S25W30 13083 GOES16  
M2.0/1N 13:45 S24W26 13078 GOES16  
M1.1 14:52   13078 GOES16 LDE, CME
C2.2 17:56   13082 GOES16  
C3.3 23:32 southwest limb 13079 GOES16 LDE

Coronal mass ejections (CMEs)

August 15: A partial halo CME was observed after the long duration C3 event in AR 13074 early in the day.
August 16: No well defined CME was observed after the M5 major flare in AR 13078, however, there is chance CME effects will reach Earth on August 18 or 19.
August 17: A faint full halo CME was observed after the M1.0 long duration event in AR 13078 peaking at 14:52 UT. The CME could reach Earth on August 20.

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 trans equatorial coronal hole (CH1094) rotated across the central meridian on August 14-17.

Propagation

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

Forecast

Quiet to minor storm conditions are expected for August 18-21 due to effects from CH1094 and the August 15 and 17 CMEs. Major storm intervals are possible.

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.
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 officially numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC, all other regions are numbered sequentially as they emerge using the STAR spot number. 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. SWPC data considered to be not sufficiently precise (location, area, classification) are colored red.

Active region SWPC date numbered
STAR detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlays
Comment
SWPC/
USAF
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13076 2022.08.06
2022.08.07
  3 2 N15W63 0005   BXO

location: N15W60

13078 2022.08.09
2022.08.10
10 34 21 S20W34 0190 DAC DAC beta-gamma-delta

area: 0340

location: S23W32

S7766 2022.08.10       S11W16          
13081 2022.08.11
2022.08.13
9 29 16 N11W08 0150 CAO DAO location: N10W11
13079 2022.08.11
2022.08.12
3 6 2 S06W78 0080 CAO AXX area: 0010

location: S11W78

S7771 2022.08.11       S27W38            
S7773 2022.08.12       N23W51            
S7775 2022.08.13       N36W35            
S7776 2022.08.14   1   N21W62 0001   AXX  
S7777 2022.08.14       N26W39            
S7778 2022.08.14   7 5 S10E35 0015   BXO  
S7779 2022.08.14       N11W26            
S7781 2022.08.15       N23W07            
13083 2022.08.15
2022.08.16
4 8 5 S24W42 0030 DAO DRO location: S25W43
13082 2022.08.15
2022.08.16
7 19 11 N23E37 0080 DAO DRI location: N27E37
S7785 2022.08.15       N16E12            
S7786 2022.08.16   2 2 S19E59 0010   HRX  
S7787 2022.08.16   7 3 N35W02 0013   BXO  
S7788 2022.08.16       S16E60          
S7789 2022.08.16   2 1 N13W25 0005   AXX  
S7790 2022.08.17   1   N12E32 0001   AXX    
Total spot count: 33 119 68  
Sunspot number: 83 269 168  (total spot count + 10 * number of spotted regions)
Weighted SN: 58 138 87  (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): 91 148 134  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (SC24 peak) 110.5 10.70
2014.04 143.9 144.8 112.5 116.4 (solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(cycle peak)
2019.11 70.2 68.7 0.5 2.0 (-0.6)
(Solar minimum using 365d smoothing:
November 17, 2019)
4.19
2019.12 70.8 68.6 1.6 1.8 (-0.2)
(ISN 13 months smoothed
solar minimum)
3.22
2021.01 76.0 73.6 10.4 17.3 (+2.0) 4.39
2021.02 74.3 72.4 8.2 19.0 (+1.7) 9.50
2021.03 76.0 75.2 17.2 21.7 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.8 (+3.1) 8.40
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
2021.06 79.4 81.8 25.0 27.6 (+1.8) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.8) 5.51
2021.08 77.7 79.7 22.0 35.4 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.2 (+4.8) 6.33
2021.10 88.9 88.3 37.4 45.2 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.8 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.9 (+5.1) 6.40
2022.01 103.8 100.5 55.3 60.1 (+4.2) 8.92
2022.02 109.1 106.5 60.9 (65.8 projected, +5.7) 10.46
2022.03 117.0 115.8 78.6 (70.8 projected, +5.0) 10.20
2022.04 130.8 131.7 84.1 (75.9 projected, +5.1) 11.79
2022.05 133.8 136.8 96.5 (82.4 projected, +6.5) 7.48
2022.06 116.1 119.8 70.5 (88.3 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (95.5 projected, +7.2) 9.51
2022.08 114.3 (1)   39.3 (2A) / 71.7 (2B) / 94.8 (2C) (102.0 projected, +6.5) (11.1)
2022.09       (106.9 projected, +4.9)  
2022.10       (110.1 projected, +3.2)  
2022.11       (112.9 projected, +2.8)  
2022.12       (117.7 projected, +4.8)  
2023.01       (123.7 projected, +6.0)  
2023.11       (142.5 projected max SC25)  

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz and any corrections applied to that measurement.
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) Source: SIDC-SILSO.

Solar cycles 24-25

Smoothed SF and sunspot numbers

 

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.