Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 7, 2022 at 10:50 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 active on February 6 under the influence of a high speed stream associated with CH1058. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 123.6 - increasing 21.4 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 84.92). The Potsdam WDC planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 13.9). Three hour interval K indices: 43333133 (planetary), 33333223 (Boulder), 54333245 (Andenes).

The background x-ray flux is at the class B5 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 8 active regions using 2K resolution (SN: 199) and in 6 active regions using 1K resolution (SN: 117) SDO/HMI images.

Region 12939 [S16W19] developed when new flux emerged to the south of the largest spot resulting in polarity intermixing. The region was the center of a C3.1 long duration event  which was associated with a full halo CME.
Region 12940 [N17W18] decayed slowly and quietly.
Region 12941 [N24E39] was mostly quiet and stable. C1 flares: C1.9 @ 01:00 UT.
New region 12942 [S12W61] emerged on February 5 and was numbered by SWPC the next day.

Spotted regions not observed (or interpreted differently) by SWPC:
S7328 [S25W21] decayed slowly and quietly.
S7332 [N15W83] was mostly quiet and stable. C1 flares: C1.4 @ 01:24, C1.0 @ 03:50 UT. That C1.4 flare was wrongly attributed to AR 12936 by SWPC-
S7339 [N13E11] was quiet and stable.
New region S7343 [S20E79] rotated into view with tiny spots.

AR 12936 was still active behind the northwest limb. C1 flares: C1.0 @ 01:45, C1.3 @ 05:12, C1.2 @ 11:24 UT.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.1 13:41 S20W07 12939 GOES16 LDE, halo CME

Coronal mass ejections (CMEs)

February 4-5: No obviously Earth directed CMEs were observed in available LASCO imagery.
February 6: A faint full halo CME was observed after a C3.1 long duration event near noon in AR 12939. The region became unstable as new flux emerged to the south of the leader spot.

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 (CH1059) was Earth facing on February 3-4. A recurrent southern hemisphere coronal hole (CH1060) will likely rotate across the central meridian on February 9-10.

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 unsettled on February 7-8 due to effects from CH1059. On February 9-10 the CME observed on February 6 could cause unsettled to minor storm conditions.

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
12938 2022.01.25
2022.01.26
4     N19W85 0030 BXO       location: N21W76

spotless

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

12939 2022.01.29
2022.01.30
4 19 11 S16W20 0200 CSO DSI

beta-gamma

location: S16W19

area: 0270

12940 2022.01.30
2022.01.30
12 47 23 N16W19 0200 DAO EAI

location: N17W18

area: 0160

S7327 2022.01.30       N18W31            
S7328 2022.01.30   4   S25W21 0005   AXX  
S7331 2022.01.31       N27W46            
S7332 2022.01.31   5 2 N15W83 0030   CRO  
12941 2022.02.02
2022.02.03
10 27 13 N24E35 0290 EHO FAI

location: N24E39

S7335 2022.02.02       S12W57            
S7336 2022.02.02       S22W18           reversed polarities
S7338 2022.02.04       S22W00          
S7339 2022.02.04   2   N13E11 0004   AXX  
12942 2022.02.05
2022.02.06
3 10 6 S11W62 0020 BXO CRI  
S7341 2022.02.05       S06W38          
S7342 2022.02.05       N00W06         probably SC24
S7343 2022.02.06   5 2 S20E79 0020   BXO    
Total spot count: 33 119 57  
Sunspot number: 83 199 117  (total spot count + 10 * number of spotted regions)
Weighted SN: 53 140 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): 91 109 94  

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
2022.02 127.1 (1)   18.0 (2A) / 84.2 (2B) / 80.1 (2C) (65.5 projected, +4.7) (16.9)
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.