Solar Terrestrial Activity Report

Activity chart

Last major update issued on March 29, 2022 at 14:15 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 (March 1, 2022)
Solar cycle Solar cycles 23-25 (March 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (March 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 (March 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (March 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 March 28 under the decreasing influence of a high speed stream from CH1070. The high latitude magnetometer at Andenes recorded quiet to major storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 156 - increasing 56.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 89.50). The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 9.4). Three hour interval K indices: 44111011 (planetary), 44313311 (Boulder), 56121113(Andenes).

The background x-ray flux was at the class C3 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 14 active regions using 2K resolution (SN: 310) and in 9 active regions using 1K resolution (SN: 177) SDO/HMI images.

Region 12974 [S19W12] was quiet and stable.
Region 12975 [N13W10] developed further and has multiple magnetic deltas. The region could produce a major flare. The M4 proton flare at 11:28 UT and a long duration C8 event peaking at 20:04 UT were both associated with full halo CMEs. C1 flares: C1.7 @ 01:30, C1.4 @ 01:52, C1.3 @ 02:04, C1.1 @ 02:20, C1.2 @ 03:22, C1.7 @ 06:42 UT.
Region 12976 [N15E07] was quiet and stable. The region still has a magnetic delta at the northern edge of the main penumbra. An M class flare is possible.
Region 12977 [N21W24] decayed slowly and quietly.
Region 12978 [S17E64] has M class flare potential and was mostly quiet. C1 flares: C1.5 @ 08:41 UT.
New region 12979 [S20E11] was first observed with spots on March 25. New flux emerged on March 27 and the region was numbered by SWPC on March 28.
New region 12980 [N08W28] emerged on March 27 and was numbered by SPWC the next day.

Spotted regions not observed (or interpreted differently) by SWPC:
S7455 [S24W58] was quiet and stable.
S7458 [S24E70] was somewhat unstable, probably due to interaction between small opposite polarity spots near the center of the region. C1 flares: C1.8 @ 00:42 UT
S7459 [N40E21] was quiet and stable.
New region S7461 [N20E38] was observed with a tiny spot in an old plage area.
New region S7462 [S13E36] was observed with tiny spots in an old plage area.
New region S7463 [S42E49] emerged with a tiny spot at a high latitude.
New region S7464 [S28E46] was observed with a tiny spot in an old plage area.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.1 01:07   12978 GOES16  
C2.1 09:57   12975 GOES16  
M4.0 11:29   12975 GOES16 LDE, halo CME, strong type II and moderate type IV radio sweep
C2.6 14:54   12975 GOES16 LDE
C5.1 16:43   12978 GOES16  
C5.0 16:49   12975 GOES16  
C9.8 17:13   12975 GOES16  
C9.7 17:24   12975 GOES16  
M1.0 17:41   12975 GOES16  
C6.3 19:00   12975 GOES16  
M1.0 19:22   12975 GOES16  
C8.0 19:36   12975 GOES16  
C8.6 20:04   12975 GOES16 Halo CME, weak type II radio sweep
M1.1 20:59 N14W11 12975 GOES16  
C4.4 21:52   12975 GOES16  
C5.5 22:31   12975 GOES16  
C3.3 23:46   12975 GOES16  

Coronal mass ejections (CMEs)

March 26-27: No obviously Earth directed CMEs were observed in available LASCO imagery.
March 28: A full halo CME was observed at noon after the M4 event in AR 12975. The CME could reach Earth on March 30 and cause unsettled to severe storm conditions. Another full halo CME was observed after a C8.6 flare in AR 12975 peaking at 20:04 UT. This CME could reach Earth early on March 31.

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 (CH1071) will likely rotate across the central meridian on March 30.

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

Quiet to unsettled conditions are likely on March 29. Quiet to major storm conditions are possible on March 30-31 if the March 28 CMEs impact Earth, isolated severe storm intervals are not unlikely.

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
12973 2022.03.19
2022.03.20
      N19W62            
S7438 2022.03.19       N17W34            
12974 2022.03.21
2022.03.22
1 7 1 S19W16 0010 AXX CRO

location: S19W12

area: 0020

S7443 2022.03.21       S24W20            
12975 2022.03.22
2022.03.23
26 68 38 N13W12 0210 DAC DAC

beta-gamma-delta

location: N13W10

area: 0450

12976 2022.03.22
2022.03.24
10 27 13 N16E08 0480 EHO EKC beta-delta

location: N15E07

S7448 2022.03.25       N18W21            
12979 2022.03.25
2022.03.28
4 18 9 S21E10 0020 BXO DRI location: S20E11

area: 0040

12977 2022.03.26
2022.03.27
8 9 5 N21W25 0040 BXO CRO area: 0020
S7453 2022.03.27       S27W22          
12978 2022.03.27
2022.03.27
4 15 8 S17E68 0210 ESO EHO

beta-gamma

location: S17E64

area: 0570

S7455 2022.03.27   2 1 S24W58 0006   BXO  
12980 2022.03.27
2022.03.28
2 8 5 N08W28 0010 BXO DRO area: 0040
S7457 2022.03.27       N25E29          
S7458 2022.03.27   9 7 S24E70 0040   DRO beta-gamma
S7459 2022.03.27   2   N40E21 0002   BXO  
S7460 2022.03.28       S33W27          
S7461 2022.03.28   1   N20E38 0002   AXX    
S7462 2022.03.28   2   S13E36 0002   BXO    
S7463 2022.03.28   1   S42E49 0001   AXX    
S7464 2022.03.28   1   S28E46 0001   AXX    
Total spot count: 55 170 87  
Sunspot number: 125 310 177  (total spot count + 10 * number of spotted regions)
Weighted SN: 75 210 127  (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): 138 171 142  

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
2020.08 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 35.3 (+3.9) 6.19
2021.09 87.0 88.2 51.3 (39.9 projected, +4.6) 6.33
2021.10 88.9 88.3 38.1 (43.6 projected, +3.7) 7.38
2021.11 86.2 84.4 35.0 (48.2 projected, +4.6) 9.83
2021.12 103.0 99.8 67.6 (54.0 projected, +5.8) 6.40
2022.01 103.8 100.5 54.0 (57.7 projected, +3.7) 8.92
2022.02 109.1 106.5 59.7 (62.4 projected, +4.7) 10.46
2022.03 113.5 (1)   60.0 (2A) / 66.5 (2B) / 85.8 (2C) (67.9 projected, +5.5) (9.9)
2022.04       (73.0 projected, +5.1)  
2022.05       (79.4 projected, +6.4)  
2022.06       (85.3 projected, +5.9)  
2022.07       (92.6 projected, +7.3)  
2022.08       (99.2 projected, +6.6)  

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.