Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 18, 2022 at 12:00 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 17. The high latitude magnetometer at Andenes recorded quiet to active levels.

Solar flux density measured at 20h UT on 2.8 GHz was 96.7 - decreasing 0.6 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 86.12). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.3). Three hour interval K indices: 21111011 (planetary), 12101212 (Boulder), 42111033 (Andenes).

The background x-ray flux is at the class B2 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 184) and in 7 active regions using 1K resolution (SN: 101) SDO/HMI images.

Region 12946 [S09W14] decayed slowly and was mostly quiet.
Region 12948 [S27E13] decayed slowly and quietly.
Region 12949 [N25W32] decayed slowly and quietly.
Region 12950 [N22E32] was mostly quiet and stable. C1 flares: C1.4 @ 20:51 UT. An EIT wave was observed with this event. At least a partial halo CME was observed first off the northwest limb at 21:24 UT, however, the origin of the CME may have been backsided.
Region 12951 [S23W14] decayed slowly and quietly.
New region 12952 [S23E68] rotated into view on February 16 and was numbered the next day by SWPC as the region decayed slowly.

Spotted regions not observed (or interpreted differently) by SWPC:
S7351 [N22W15] reemerged with a tiny spot.
S7359
[S20W65] decayed slowly and quietly.
New region S7366 [S23W27] emerged with tiny spots before noon, then decayed slowly.
New region S7368 [S09E04] emerged with tiny spots.
New region S7369 [N17E38] emerged with a tiny spot.

AR 12941 behind the northwest limb produced a C1.0 flare at 03:24 UT.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.3 06:02 behind NW limb 12941 GOES16  

Coronal mass ejections (CMEs)

February 15-17: 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) will be Earth facing on February 17-18.

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 on February 18-19 and quiet to active on February 20-21 due to effects from CH1064.

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
12943 2022.02.06
2022.02.08
5     S21W66
real location: S18W76
0020 BXO       the region is spotless
SWPC has "moved" the region to the spots observed in AR S7359, 11 degrees further east
S7345 2022.02.08       S22W48            
12946 2022.02.10
2022.02.11
3 16 4 S10W15 0010 BXO BXO  
S7351 2022.02.10   1   N22W15 0001   AXX    
12951 2022.02.11
2022.02.16
4 7 3 S24W15 0010 BXO BXO  
S7355 2022.02.12       S38W47            
12948 2022.02.13
2022.02.14
13 28 16 S27E15 0100 CAO CAO location: S27E13
S7359 2022.02.14   6 2 S20W65 0010   BXO  
12949 2022.02.14
2022.02.16
6 6 4 N24W32 0010 BXO CRO

area: 0020

S7361 2022.02.14       N46W40            
12950 2022.02.14
2022.02.16
1 2 1 N21E33 0020 HRX BXO  
S7363 2022.02.14       S18W32            
S7364 2022.02.15       N22E09            
12952 2022.02.16
2022.02.17
1 1 1 S24E67 0020 HRX HRX location: S23E68
S7366 2022.02.17   2   S23W27 0002   BXO  
S7367 2022.02.17       N19E49         reversed polarities
S7368 2022.02.17   3   S09E04 0005   BXO    
S7369 2022.02.17   1   N17E38 0002   AXX    
Total spot count: 33 73 31  
Sunspot number: 103 183 101  (total spot count + 10 * number of spotted regions)
Weighted SN: 44 84 42  (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): 113 101 81  

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
2022.02 117.9 (1)   49.2 (2A) / 81.0 (2B) / 84.8 (2C) (65.5 projected, +4.7) (12.4)
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.