Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 21, 2022 at 07:40 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 (February 1, 2022)
Solar cycle Solar cycles 23-25 (February 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (February 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (June 1, 2020) POES auroral activity level October 2009 - December 2012]
  Comparison of cycles 21-25 (February 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (February 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 22, 2021) 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 minor storm on February 20 under the influence of a high speed stream associated with CH1064. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 93.3 - decreasing 1.9 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 86.28). The Potsdam WDC planetary A index was 13 (STAR Ap - based on the mean of three hour interval ap indices: 13.1). Three hour interval K indices: 54220232 (planetary), 43111222 (Boulder), 44212534 (Andenes).

The background x-ray flux is at the class B1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 8 active regions using 2K resolution (SN: 115) and in 6 active regions using 1K resolution (SN: 77) SDO/HMI images.

Region 12948 [S27W25] decayed slowly and quietly.
Region 12952 [S23E29] was quiet and stable.
Region 12953 [N18E23]was quiet and stable.
New region 12954 [N18E73] rotated into view early in the day.

Spotted regions not observed (or interpreted differently) by SWPC:
S7375 [S14W56] decayed early in the day, then reemerged with spots after noon.
New region S7378 [N14E88] rotated partly into view. M class flares are possible.
New region S7379 [N22W01] was observed with faint, tiny spots in an old plage area.
New region S7380 [S27E00] was observed with tiny spots in an old plage area.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C5.1 04:07 N16E90 S7378 GOES16  

Coronal mass ejections (CMEs)

February 18-20: 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 northern hemisphere coronal hole (CH1064) was Earth facing on February 17-18. A small northern hemisphere coronal hole (CH1065) will likely rotate into an Earth facing position on February 22.

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.

Forecast

The geomagnetic field is expected to be quiet to unsettled on February 21 due to effects from CH1064 and quiet on February 22-23.

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
12946 2022.02.10
2022.02.11
      S08W56          
S7351 2022.02.10       N22W54            
12951 2022.02.11
2022.02.16
      S25W55         location: S23W54
12948 2022.02.13
2022.02.14
4 7 3 S27W24 0030 CSO CRO  
12949 2022.02.14
2022.02.16
      N24W73        

 

12950 2022.02.14
2022.02.16
      N22W09           location: N22W04
S7364 2022.02.15       N22W30            
12952 2022.02.16
2022.02.17
1 3 2 S24E29 0010 AXX HRX area: 0020
S7367 2022.02.17       N19E10           reversed polarities
S7368 2022.02.17       S09W35            
S7369 2022.02.17       N17W01            
12953 2022.02.18
2022.02.19
3 15 8 N17E22 0020 BXO DRI area: 0040
S7371 2022.02.18       N22E26          
S7372 2022.02.18       S11E08            
S7373 2022.02.18       N28W27            
S7374 2022.02.19       S23W36          
S7375 2022.02.19   3 2 S14W56 0008   BXO  
S7376 2022.02.19       N13E02          
12954 2022.02.20
2022.02.20
1 1 1 N17E72 0060   HSX   was AR S7377

area: 0120

S7378 2022.02.20   1   N14E88 0190   HSX    
S7379 2022.02.20   3 1 N22W01 0006   AXX    
S7380 2022.02.20   2   S27E00 0001   AXX    
Total spot count: 9 35 17  
Sunspot number: 49 115 77  (total spot count + 10 * number of spotted regions)
Weighted SN: 19 51 33  (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): 54 63 62  

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
2020.07 69.5 71.8 6.1 9.0 (+1.1) 4.28
2020.08 71.6 73.4 7.5 9.5 (+0.5) 5.68
2020.09 70.7 71.4 0.7 10.5 (+1.0) 8.59
2020.10 74.6 74.2 14.6 11.9 (+1.4) 6.13
2020.11 89.9 88.0 34.5 13.6 (+1.7) 4.77
2020.12 86.9 84.2 23.1 15.3 (+1.7) 4.72
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 27.7 (+1.9) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.7) 5.51
2021.08 77.7 79.7 22.0 (36.2 projected, +4.8) 6.19
2021.09 87.0 88.2 51.3 (42.3 projected, +6.1) 6.33
2021.10 88.9 88.3 38.1 (46.7 projected, +4.4) 7.38
2021.11 86.2 84.4 35.0 (51.3 projected, +4.6) 9.83
2021.12 103.0 99.8 67.6 (57.2 projected, +5.9) 6.40
2022.01 103.8 100.5 54.0 (60.8 projected, +3.6) 8.92
2022.02 114.3 (1)   54.6 (2A) / 76.5 (2B) / 85.5 (2C) (65.5 projected, +4.7) (11.8)
2022.03       (71.0 projected, +5.5)  
2022.04       (76.1 projected, +5.1)  
2022.05       (82.6 projected, +6.5)  
2022.06       (88.4 projected, +5.9)  
2022.07       (95.7 projected, +7.3)  

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.