Solar Terrestrial Activity Report

Activity chart

Last major update issued on August 29, 2022 at 10:25 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 unsettled on August 28 under the effects of a weak high speed coronal hole stream. Solar wind speed at SOHO ranged between 382 and 554 km/sec. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. A solar wind shock was observed at DSCOVR at 02:57 UT, the arrival of either the August 26 or 27 CME.

Solar flux density measured at 23h UT on 2.8 GHz was 133.5 - increasing 38.1 over the previous solar rotation (the measurements at 17 and 20h UT were flare enhanced). (Centered 1 year average SF at 1 AU - 183 days ago: 109.65). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.9). Three hour interval K indices: 21132221 (planetary), 21233322 (Boulder), 32132222 (Andenes).

The background x-ray flux is at the class C3 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 207) and in 7 active regions using 1K resolution (SN: 122) SDO/HMI images.

Region 13085 [N30W75] decayed slowly and quietly.
Region 13086 [S23W24] decayed slowly and quietly.
Region 13087 [S14W00] was quiet and stable.
Region 13088 [S28W84] rotated partly out of view producing many C and M flares. A major proton flare is possible for the next day or so while the region rotates over the limb.
Region 13089 [S22E18] gained area and many spots. A magnetic delta structure formed in the trailing spot section and a major flare is possible.
Region 13090 [N17E27] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC:
S7811 [N13W28] decayed slowly and quietly.
S7817 [S20W01] decayed slowly and quietly.
New region S7820 [S03W21] emerged with tiny spots.
New region S7821 [N15E38] emerged with tiny spots.
New region S7822 [N24E73] rotated into view with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
M1.4 01:34   13088 GOES16 LDE
C9.5 01:49   13088 GOES16  
C5.9 02:20   13088 GOES16  
C7.4 02:41   13088 GOES16  
C4.5 03:39   13088 GOES16  
C4.5 04:34   13088 GOES16  
C3.0/1N 05:52   13088 GOES16  
C3.0 06:03   13088 GOES16  
C3.3 06:53   13088 GOES16  
C5.3 07:07   13088 GOES16  
C9.9 07:48   13088 GOES16 LDE
C3.1 11:25   13088 GOES16  
C3.0 12:05   13088 GOES16  
C5.3 13:32   13088 GOES16  
M6.7 16:19   13088 GOES16 LDE, CME, weak type II and IV radio sweeps
M4.6 18:32   13088 GOES16  
C4.6 23:16   13089 GOES16  
C7.5 23:36   13088 GOES16  

Coronal mass ejections (CMEs)

August 26: A partial halo CME was observed after the M3.6 LDE in AR 13088. The event peaked at 13:16 UT and the CME core was headed towards the west southwest. Earth could see an impact on August 28-29.
August 27: A partial halo CME was observed after the M4.8 LDE in AR 13088 early in the day. Earth could see an impact on August 29.
August 28: 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 southern hemisphere coronal hole (CH1096) rotated across the central meridian on August 25-27.

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 possible on August 29-30 due to effects from CH1096 and CME effects. Quiet to unsettled is expected for August 31.

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
13085 2022.08.20
2022.08.21
1 2 2 N30W76 0080 HSX HAX

area: 0130

13086 2022.08.21
2022.08.23
6 19 6 S23W25 0030 CRO DRO location: S23W24

area: 0060

S7803 2022.08.21       N20W25            
S7804 2022.08.21       N28W42            
S7806 2022.08.22       N08W40            
13087 2022.08.22
2022.08.23
1 4 2 S14W01 0010 AXX HRX  
13090 2022.08.23
2022.08.25
  5 1 N16E20 0008   BXO location: N17E27
13088 2022.08.24
2022.08.25
4 6 3 S27W87 0220 DKC DAC

location: S28W84

13089 2022.08.24 17 52 37 S23E18 0320 EKI EKC beta-gamma

location: S22E18

area: 0450

S7811 2022.08.25   1   N13W28          
S7813 2022.08.25       N03W38            
S7814 2022.08.25       N34W19            
S7815 2022.08.26       S22W18            
S7816 2022.08.26       S13E50            
S7817 2022.08.27   2   S21W16 0004   BXO  
S7818 2022.08.27       N11W08          
S7819 2022.08.27       N09W10          
S7820 2022.08.28   2   S03W21 0004   BXO    
S7821 2022.08.28   3 1 N15E38 0006   BXO    
S7822 2022.08.28   1   N24E73 0001   AXX    
Total spot count: 29 97 52  
Sunspot number: 79 207 122  (total spot count + 10 * number of spotted regions)
Weighted SN: 57 123 78  (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): 87 114 98  

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
2022.08 113.3 (1)   63.7 (2A) / 70.5 (2B) / 94.6 (2C) (102.0 projected, +6.5) (10.9)
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.