Solar Terrestrial Activity Report

Activity chart

Last major update issued on August 31, 2022 at 07:15 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 30 under the combined CME and coronal hole effects. A solar wind shock was recorded at DSCOVR at 18:51 UT. Solar wind speed at SOHO ranged between 430 and 698 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 125.6 - increasing 25.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 109.86). The Potsdam WDC planetary A index was 13 (STAR Ap - based on the mean of three hour interval ap indices: 13.0). Three hour interval K indices: 24332123 (planetary), 24232323 (Boulder), 45322234 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 7 active regions using 2K resolution (SN: 139) and in 4 active regions using 1K resolution (SN: 72) SDO/HMI images.

Region 13086 [S23W52] decayed slowly and quietly.
Region 13087 [S16W23] decayed slowly and quietly.
Region 13089 [S22W08] gained area and was mostly quiet despite the magnetic delta in the trailing spot section. A major flare is possible. C1 flares: C1.2 @ 14:13 UT
Region 13090 [N18W02] was quiet and stable.

Spotted regions not observed (or interpreted differently) by SWPC:
S7817 [S21W43] was quiet and stable.
S7821 [N14E11] reemerged with tiny spots.
New region S7825 [S26E50] was observed with a tiny spot in an old plage area.

AR 13088 produced many C and M flares while 1 day behind the southwest limb. C1 flares: C1.6 @ 10:59 UT

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
M1.7 01:40 behind SW limb 13088 GOES17  
M1.5 02:13 behind SW limb 13088 GOES17  
C7.6 04:57 behind SW limb 13088 GOES17  
C2.4 08:32 behind SW limb 13088 GOES17 incorrectly attributed to AR 13089 by SWPC
C3.0 11:43 behind SW limb 13088 GOES17  
C2.1 16:47 behind SW limb 13088 GOES17  
C5.4 17:20 behind SW limb 13088 GOES17  
C7.1 17:49 behind SW limb 13088 GOES17  
M2.1 19:29 behind SW limb 13088 GOES17 Very long duration event. Backsided full halo CME

Coronal mass ejections (CMEs)

August 28-30: No obviously 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 large trans equatorial coronal hole (CH1097) will likely become Earth facing on September 1-2.

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 active conditions are possible on August 31 due to effects from CH1096 and CME effects. Quiet to unsettled is expected for September 1-3 becoming quiet to minor storm on September 4-5 due to effects from CH1097.

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
13086 2022.08.21
2022.08.23
2 5   S23W53 0030 DSO BXO location: S23W52

area: 0008

S7803 2022.08.21       N20W51            
13087 2022.08.22
2022.08.23
  3   S14W27 0003   BXO  
13090 2022.08.23
2022.08.25
  3 2 N16W08 0007   BXO location: N18W02
13089 2022.08.24 28 51 28 S22W06 0250 EAC FAC beta-gamma-delta

location: S22W08

area: 0650

S7811 2022.08.25       N13W54            
S7814 2022.08.25       N34W45            
S7815 2022.08.26       S22W44            
S7816 2022.08.26       S13E24            
S7817 2022.08.27   2 1 S21W43 0004   BXO  
S7818 2022.08.27       N11W34            
S7819 2022.08.27       N09W36            
S7820 2022.08.28       S03W47            
S7821 2022.08.28   4 1 N14E11 0008   AXX    
S7822 2022.08.28       N25E47          
S7823 2022.08.29       N07E43          
S7824 2022.08.29       S12E23          
S7825 2022.08.30   1   S26E50 0001   AXX    
Total spot count: 30 69 32  
Sunspot number: 50 139 72  (total spot count + 10 * number of spotted regions)
Weighted SN: 40 74 37  (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): 55 76 58  

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)   68.1 (2A) / 70.4 (2B) / 94.6 (2C) (102.0 projected, +6.5) (11.0)
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.