Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 24, 2022 at 08:35 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 on February 23. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 95.5 - decreasing 11.6 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 86.44). The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.8). Three hour interval K indices: 10222222 (planetary), 10222212 (Boulder), 20113445 (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 5 active regions using 2K resolution (SN: 75) and in 4 active regions using 1K resolution (SN: 52) SDO/HMI images.

Region 12953 [N18W14] decayed slowly and quietly.
Region 12954 [N17E33] was quiet and stable.
Region 12955 [N14E45] was quiet and stable.

Spotted regions not observed (or interpreted differently) by SWPC:
New region S7385 [N13E13] emerged with tiny spots.
New region S7386 [N26W02] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
           

Coronal mass ejections (CMEs)

February 21-23: 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 small northern hemisphere coronal hole (CH1065) rotated into an Earth facing position on February 22. A trans equatorial coronal hole (CH1066) will rotate across the central meridian on February 24-26.

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 24-26. On February 27-28 quiet to active conditions are expected as a high speed stream associated with CH1066 becomes the dominant solar wind source.

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
12948 2022.02.13
2022.02.14
      S28W67         location: S27W59
12950 2022.02.14
2022.02.16
      N22W51           location: N22W43
12952 2022.02.16
2022.02.17
      S24W13           location: S23W08
S7367 2022.02.17       N19W29           reversed polarities
S7369 2022.02.17       N17W40            
12953 2022.02.18
2022.02.19
5 6 3 N17W18 0010 BXO CRO  
S7371 2022.02.18       N22W13            
S7372 2022.02.18       S11W31            
S7376 2022.02.19       N12W37          
12954 2022.02.20
2022.02.20
1 4 1 N17E31 0110 HSX CSO location: N17E33

area: 0140

12955 2022.02.20
2022.02.21
2 8 4 N15E44 0140 CSO DSO area: 0200

location: N14E45

S7379 2022.02.20       N23W41            
S7380 2022.02.20       S26W39          
S7381 2022.02.21       S15W19            
S7382 2022.02.21       N04E01           likely SC24
S7383 2022.02.21       N29W24            
S7384 2022.02.22       S20W26          
S7385 2022.02.23   6 4 N13E13 0015   BXO    
S7386 2022.02.23   1   N26W02 0002   AXX    
Total spot count: 8 25 12  
Sunspot number: 38 75 52  (total spot count + 10 * number of spotted regions)
Weighted SN: 18 38 25  (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): 42 41 42  

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
2022.02 112.0 (1)   59.1 (2A) / 71.9 (2B) / 86.5 (2C) (65.5 projected, +4.7) (11.7)
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.