Solar Terrestrial Activity Report

Activity chart

Last major update issued on December 30, 2022 at 11:30 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 (December 4, 2022)
Solar cycle Solar cycles 23-25 (December 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (December 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (July 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (December 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (December 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 21, 2022) 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 December 29 as a disturbance related to CH1122 started after 04h UT according to DSCOVR data (no CIR was observed due the weak western part of CH1122). Solar wind speed at SOHO ranged between 433 and 509 km/sec. The high latitude magnetometer at Andenes recorded quiet to severe storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 160. The Potsdam WDC planetary A index was 10 (STAR Ap - based on the mean of three hour interval ap indices: 10.5). Three hour interval K indices: 00223334 (planetary), 01224333 (Boulder), 00113457 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 263) and in 10 active regions using 1K resolution (SN: 163) SDO/HMI images.

Region 13169 [N23W79] rotated partly out of view and decayed.
Region 13171 [N23W63] decayed slowly and quietly.
Region 13172 [S36W34] decayed slowly and quietly.
Region 13173 [N23W14] decayed slowly and quietly.
Region 13175 [S21E06] decayed slowly and quietly.
Region 13176 [N19E24] developed further and may be capable of M class flaring.
Region 13177 [S18E57] was mostly quiet and stable.
Region 13178 [S04W68] decayed slowly and quietly.
Region 13179 [N13W10] was first observed with spots on December 28 and developed quickly on December 29 when it was numbered by SWPC.

Spotted regions not observed (or interpreted differently) by SWPC:
S8130 [N31W63] reemerged with a few spots.
New region S8133 [N19E82] rotated partly into view. The two leader spots are latitudinally at some distance from each and may be 2 separate regions.
New region S8134 [S38E01] emerged with a tiny spot.

Coronal mass ejections (CMEs)

December 27-29: 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 northern hemisphere coronal hole (CH1122) rotated across the central meridian on December 25-27. A recurrent trans equatorial coronal hole (CH1123) will likely become Earth facing on January 1-2.

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 minor storm conditions are expected for December 30-31 due to effects from CH1122. Mostly quiet conditions are likely on January 1-3. Quiet to minor storm conditions are expected on January 4-5 due to effects from CH1123.

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
13169 2022.12.16
2022.12.17
1 6 4 N23W84 0040 HAX BXO location: N23W79
13171 2022.12.18
2022.12.19
2 8 3 N23W65 0040 HSX CAO location: N23W63
13172 2022.12.20
2022.12.21
4 11 6 S36W34 0010 BXO CRO  
13173 2022.12.22
2022.12.22
3 9 5 N25W16 0030 HSX CAO

location: N23W14

13175 2022.12.24
2022.12.25
  12   S20E03 0020   CRO location: S21E06
S8120 2022.12.24       N20W35            
S8121 2022.12.24       S07W34            
S8123 2022.12.25       S17W34            
13176 2022.12.25
2022.12.26
14 47 21 N19E24 0380 EKI EKI beta-gamma

area: 0630

13178 2022.12.27
2022.12.29
2 6 2 S03W70 0060 CSO DAO

location: S04W68

13177 2022.12.27
2022.12.28
3 14 7 S18E58 0120 DSO DSI area: 0320
S8128 2022.12.27       N05E05            
S8129 2022.12.27       N18W44            
S8130 2022.12.27   2 1 N31W63 0015   CRO    
13179 2022.12.28
2022.12.29
4 23 12 N13W11 0030 CAO DRI

location: N13W10

area: 0100

S8133 2022.12.29   4 2 N19E82 0300   DAO   two groups?
S8134 2022.12.29   1   S38E01 0001   AXX    
Total spot count: 33 143 63  
Sunspot number: 113 263 163  (total spot count + 10 * number of spotted regions)
Weighted SN: 78 190 110  (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): 124 145 130  

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
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
2021.06 79.4 81.8 25.0 27.6 (+1.8) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.8) 5.51
2021.08 77.7 79.7 22.0 35.4 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.2 (+4.8) 6.33
2021.10 88.9 88.3 37.4 45.2 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.8 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.9 (+5.1) 6.40
2022.01 103.8 100.5 55.3 60.1 (+4.2) 8.92
2022.02 109.1 106.5 60.9 64.8 (+4.7) 10.46
2022.03 117.0 115.8 78.6 68.9 (+4.1) 10.20
2022.04 130.8 131.7 84.0 73.1 (+4.2) 11.79
2022.05 133.8 136.8 96.5 77.3 (+4.2) 7.48
2022.06 116.1 119.8 70.3 (80.7 projected, +3.6) 8.20
2022.07 125.4 129.5 91.4 (85.7 projected, +5.0) 9.51
2022.08 114.2 117.1 75.4 (91.4 projected, +5.7) 10.92
2022.09 135.1 136.5 96.3 (96.3 projected, +4.9) 12.18
2022.10 133.5 132.7 95.4 (99.5 projected, +3.2) 11.16
2022.11 123.4 120.7 77.6 (102.3 projected, +2.8) 9.33
2022.12 146.8 (1)   103.3 (2A) / 110.7 (2B) / 131.5 (2C) (107.1 projected, +4.8) (10.4)
2023.01       (113.1 projected, +6.0)  
2023.02       (118.1 projected, +5.0)  
2023.03       (121.2 projected, +3.1)  
2023.04       (126.6 projected, +5.4)  
2023.05       (132.4 projected, +5.8)  
2023.11       (142.5 projected max SC25)  

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.