Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 4, 2022 at 12:30 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 3 under the influence of CME effects. The high latitude magnetometer at Andenes recorded quiet to major storm levels..

Solar flux density measured at 20h UT on 2.8 GHz was 126.5 - increasing 19.2 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 84.49). The Potsdam WDC planetary A index was 26 (STAR Ap - based on the mean of three hour interval ap indices: 26.4). Three hour interval K indices: 24554332 (planetary), 24554223 (Boulder), 35554364 (Andenes).

The background x-ray flux is at the class B8 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 246) and in 7 active regions using 1K resolution (SN: 133) SDO/HMI images.

Region 12936 [N17W62] gained area in the central spot section while decay was observed in the trialing spots. An M class flare is possible. C1 flares: C1.0 @ 01:02, C1.5 at 05:33, C1.7 @ 08:34, C1.9 11:17, C1.1 @ 19:40, C1.3 @ 20:43 UT
Region 12938 [N21W33] reemerged with tiny spots. Note that SWPC is confusing this region with AR S7332.
Region 12939 [S15E21] was quiet and stable.
Region 12940 [N17E20] decayed and had no polarity intermixing by the end of the day. C1 flares: C1.5 @ 13:58 UT.
New region 12941 [N23E77] rotated partly into view on February 2 with the last spots becoming visible late on February 3. The region has polarity intermixing and an M class flare is possible.

Spotted regions not observed (or interpreted differently) by SWPC:
S7323 [S26W28] was quiet and stable.
S7327 [N18E09] reemerged with a tiny spot.
S7328 [S25E19] developed slowly and quietly.
S7332 [N15W48] decayed slowly and quietly.
S7336 [S22E21] decayed slowly and quietly during the latter half of the day.
New region S7337 [N21W47] emerged early in the day, then decayed slowly.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.2 23:43 N17W68 12936 GOES16  

Coronal mass ejections (CMEs)

February 1-3: 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 recurrent trans equatorial coronal hole (CH1058) rotated across the central meridian on February 1-2. A southern hemisphere coronal hole (CH1059) was Earth facing on February 3-4.

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

The geomagnetic field is expected to be quiet to active on February 4 due to CME effects. On February 5-8 quiet to active conditions are likely due to effects from CH1058 and CH1059.

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
12936 2022.01.23
2022.01.25
12 29 13 N17W62 0650 EKI EKI beta-gamma-delta
12938 2022.01.25
2022.01.26
1 4   N14W48 0010 HRX BXO   location: N21W47

SWPC has failed to observe AR S7332 and uses data from that region

S7323 2022.01.29   1   S26W28 0001   AXX  
12939 2022.01.29
2022.01.30
4 22 14 S16E22 0260 DHO DSO

location: S15E21

12940 2022.01.30
2022.01.30
14 53 23 N17E20 0180 CAI ESI

location: N17E33

S7327 2022.01.30   1   N18E09 0002   AXX    
S7328 2022.01.30   11 6 S25E19 0030   BXO  
S7329 2022.01.30       S17W28            
S7330 2022.01.30       S06W27            
S7331 2022.01.31       N27W07            
S7332 2022.01.31   5 1 N15W48 0010   CRO  
S7333 2022.02.01       S26W29            
12941 2022.02.02
2022.02.03
3 8 5 N25E71 0180 CAO EAI beta-gamma

area: 0400

S7335 2022.02.02       S12W18          
S7336 2022.02.02   1 1 S22E21 0004   AXX reversed polarities
S7337 2022.02.03   1   N21W47 0001   AXX  
Total spot count: 34 136 63  
Sunspot number: 84 246 133  (total spot count + 10 * number of spotted regions)
Weighted SN: 67 164 91  (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): 92 135 106  

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) 8.9
2022.02 127.8 (1)   8.8 (2A) / 82.3 (2B) / 74.0 (2C) (65.5 projected, +4.7) (14.3)
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.