Solar Terrestrial Activity Report

Activity chart

Last major update issued on December 14, 2022 at 09:35 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 on December 13. Solar wind speed at SOHO ranged between 374 and 461 km/sec. The high latitude magnetometer at Andenes recorded quiet to unsettled levels.

Solar flux density measured at 20h UT on 2.8 GHz was 153.0 - increasing 20.1 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 122.78). The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.3). Three hour interval K indices: 20001101 (planetary), 21111211 (Boulder), 30000002 (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 20 active regions using 2K resolution (SN: 396) and in 18 active regions using 1K resolution (SN: 281) SDO/HMI images.

Region 13153 [S17W77] rotated partly out of view producing a few low level C flares. C1 flares: C1.7 @ 09:04, C1.9 @ 19:55 UT
Region 13156 [N25W76] decayed slowly and quietly. SWPC is including the spots of AR S8076 in this region.
Region 13157 [N16W68] decayed slowly and quietly.
Region 13160 [N22W15] was quiet and stable.
Region 13162 [S13E04] was quiet and stable.
Region 13163 [S20E26] developed slowly and quietly. C and M class flares are possible. C1 flares: C1.6 @ 04:59, C1.7 @ 12:11 UT
Region 13164 [S20W59] decayed slowly and quietly.
Region 13165 [S20W36] developed further and has polarity intermixing. C and M class flares are possible. The was the source of 2 M class events between 07 and 09 UT on December 14.
Region 13166 [S08E17] developed slowly and quietly.
New region 13167 [N19E01] emerged on December 12 and continued to develop quickly on December 13 when the region was numbered by SWPC. C and M class flares are possible, however, the region is currently not very complex.

Spotted regions not observed (or interpreted differently) by SWPC:
S8076 [N28W81] decayed slowly and quietly.
S8081 [N17W09] decayed slowly and quietly.
S8085 [S19W32] decayed slowly and quietly.
S8088 [S32W06] lost the spot from the previous day while gaining 2 spots further north.
New region S8090 [S23W75] emerged with a tiny spot.
New region S8091 [N26E38] emerged with tiny spots.
New region S8092 [S15E81] rotated into view with a few mature spots.
New region S8093 [S45E24] emerged at a high latitude with a tiny spot.
New region S8094 [S09E24] was split off from AR 13166 as the regions have separate sets of opposite polarity areas.
New region S8095 [S43E05] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.9/1F 23:25 S14W79 13153 GOES16  

Coronal mass ejections (CMEs)

December 11-13: 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 southern hemisphere coronal hole (CH1119) will rotate across the central meridian on December 14-15. CH1119 could be too far to the south to cause a disturbance. A recurrent northern hemisphere coronal hole (CH1120) could become Earth facing on December 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 fair to good. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet geomagnetic conditions are expected for December 14-16. A high speed stream from CH1119 could cause a few unsettled and active intervals on December 17-18.

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
13153 2022.11.30
2022.12.01
7 7 6 S15W85 0400 FHO CRO

location: S17W77

area: 0060

13156 2022.12.01
2022.12.02
6 2 1 N26W80 0080 CSO AXX location: N25W76

area: 0004

SWPC includes the spots of AR S8057 in this region

13061 2022.12.02
2022.12.08
      N26W72           location: N24W64
13157 2022.12.03
2022.12.03
6 4 3 N16W62 0160 CSO CSO

location: N16W68

13159 2022.12.05
2022.12.06
      N29W31           location: N29W25
13164 2022.12.05
2022.12.11
2 3 3 S20W59 0010 BXO DRO

area: 0030

13160 2022.12.06
2022.12.06
1 6 2 N22W16 0080 HSX CSO

location: N22W15

area: 0100

13162 2022.12.07
2022.12.09
1 7 4 S13E03 0090 HSX CSO area: 0130

location: S13E04

S8073 2022.12.08       N28W49            
13163 2022.12.09
2022.12.10
14 47 23 S20E28 0200 ESO EKI location: S20E26

area: 0390

S8075 2022.12.09       S24W14            
S8076 2022.12.09   4 1 N28W81 0040   CRO  
S8077 2022.12.09       S13W24            
13165 2022.12.10
2022.12.11
12 39 21 S20W38 0050 DSO DRI beta-gamma

area: 0120

location: S20W36

13166 2022.12.10
2022.12.11
1 15 7 S09E16 0010 AXX DRI area: 0040

location: S08E17

S8080 2022.12.10       S03W18            
S8081 2022.12.11   6 3 N17W09 0012   BXO  
S8082 2022.12.11       S24W23            
13167 2022.12.12
2022.12.13
9 29 18 N20W01 0180 DAI DAI area: 0350

location: N19E01

S8084 2022.12.12       N20E07          
S8085 2022.12.12   3 1 S19W32 0010   CRO  
S8087 2022.12.12       N29W05          
S8088 2022.12.12   2   S32W06 0005   AXX  
S8090 2022.12.13   1 1 S23W75 0003   AXX    
S8091 2022.12.13   3 2 N26E38 0010   BXO    
S8092 2022.12.13   3 2 S15E81 0140   HSX    
S8093 2022.12.13   1 1 S45E24 0002   AXX    
S8094 2022.12.13   3 2 S09E24 0007   BXO    
S8095 2022.12.13   1   S43E05 0001   AXX    
Total spot count: 59 196 101  
Sunspot number: 159 396 281  (total spot count + 10 * number of spotted regions)
Weighted SN: 104 249 154  (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): 175 218 225  

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
2022.12 142.1 (1)   44.5 (2A) / 106.1 (2B) / 106.5 (2C) (107.1 projected, +4.8) (10.1)
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.