Solar Terrestrial Activity Report

Activity chart

Last major update issued on August 22, 2022 at 09:25 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 (August 21, 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 active on August 21 under the influence of CME effects. Solar wind speed at SOHO ranged between 490 and 720 km/sec. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 97.0 - decreasing 5.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 109.03). The Potsdam WDC planetary A index was 13 (STAR Ap - based on the mean of three hour interval ap indices: 13.4). Three hour interval K indices: 32232432 (planetary), 32233432 (Boulder), 54123444 (Andenes).

The background x-ray flux is at the class B3 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 161) and in 8 active regions using 1K resolution (SN: 111) SDO/HMI images.

Region 13081 [N10W67] was mostly quiet and stable.
Region 13082 [N28W15] decayed slowly and quietly.
Region 13084 [S09W22] developed slowly and quietly.
New region 13085 [N30E15] emerged on August 20 and was numbered by SWPC the next day. The region is developing fairly quickly and could soon become capable of M class flaring. C1 flare: C1.1 @ 20:11 UT.

Spotted regions not observed (or interpreted differently) by SWPC:
S7786 [S20E09] was quiet and stable.
S7794 [S18W21] was quiet and stable.
S7799 [S12W15] decayed slowly and quietly.
New region S7802 [S22E69] emerged with a tiny spot.
New region S7803 [N20E66] emerged with tiny spots.
New region S7804 [N28E49] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.9 03:17   13084 GOES16  
C2.0 18:14   13078 GOES16  
C2.4 23:41   13085 GOES16  

Coronal mass ejections (CMEs)

August 19: A partial halo CME was observed after the M1.6 flare in AR 13078 at 04:44 UT. There is a chance effects from this CME could reach Earth on August 22.
August 20-21: No obvious Earth directed CMEs were observed.

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 small southern hemisphere coronal hole (CH1095) was Earth facing on August 19.

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 fair.

Forecast

Quiet to active conditions are expected for August 22 due to effects from the August 17-19 CMEs. Minor and major storm intervals are possible. Quiet to unsettled conditions are possible on August 23 due to effects from CH1095.

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
13078 2022.08.09
2022.08.10
      S24W88         location: S23W85
13081 2022.08.11
2022.08.13
5 8 5 N11W66 0090 HAX CAO location: N10W67
13084 2022.08.14 3 5 2 S11W19 0010 BXO CRO location: S09W22
13082 2022.08.15
2022.08.16
2 7 3 N28W11 0010 BXO CRO location: N27W15
S7785 2022.08.15       N16W40            
S7786 2022.08.16   8 2 S20E09 0012   BXO  
S7787 2022.08.16       N36W52            
S7788 2022.08.16       S16E08            
S7790 2022.08.17       N13W20          
S7791 2022.08.18       N22W58            
S7792 2022.08.18       N30E14            
S7794 2022.08.19   2 1 S18W21 0004   BXO  
S7795 2022.08.19       N18W35            
S7796 2022.08.19       N14W10            
S7797 2022.08.20       S21W46            
13085 2022.08.20
2022.08.21
6 20 12 N29E16 0050 DAO DAI area: 0120

location: N30E15

S7799 2022.08.20   7 5 S12W15 0015   CRO  
S7800 2022.08.20       N05W10          
S7801 2022.08.20       S23W33          
S7802 2022.08.21   1   S22E69 0001   AXX    
S7803 2022.08.21   2 1 N20E68 0007   BXO    
S7804 2022.08.21   1   N28E49 0001   AXX    
Total spot count: 16 61 31  
Sunspot number: 56 161 111  (total spot count + 10 * number of spotted regions)
Weighted SN: 29 80 50  (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): 62 89 89  

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
2022.08 112.5 (1)   48.0 (2A) / 70.9 (2B) / 89.7 (2C) (102.0 projected, +6.5) (12.6)
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.