Solar Terrestrial Activity Report

Activity chart

Last major update issued on December 5, 2022 at 07:50 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 (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 4. An unexpected disturbance (transient) was observed arriving at DSCOVR just after noon resulting in severe geomagnetic storm levels at high latitudes. Solar wind speed at SOHO ranged between 487 and 596 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 143.7 - increasing 9.1 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 121.14). The Potsdam WDC planetary A index was 16 (STAR Ap - based on the mean of three hour interval ap indices: 15.8). Three hour interval K indices: 22123444 (planetary), 22234444 (Boulder), 31014765 (Andenes).

The background x-ray flux is at the class B7 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 9 active regions using 2K resolution (SN: 230) and in 7 active regions using 1K resolution (SN: 142) SDO/HMI images.

Region 13153 [S16E32] produced a single small C flare. Small intermediate spots developed after noon, and if this development continues, the region could become more unstable. A major flare is possible.
Region 13154 [S38W43] decayed slowly and quietly.
Region 13155 [N23W22] developed slowly and produced several low C flares. C1 flares: C1.4 @ 16:24, C1.5 @ 18:16, C1.7 @ 18:27, C1.6 @ 21:59 UT
Region 13156 [N25E39] was mostly quiet and stable. C1 flares: C1.3 @ 02:18 UT
Region 13157 [N17E59] developed slowly and quietly. The region has weak polarity intermixing.
New region 13158 [N25E08] was first observed with spots on November 30 with SWPC numbering the region 4 days later as slow development continued. Minor polarity intermixing increases the chance of C flares from this group.

Spotted regions not observed (or interpreted differently) by SWPC:
S8056 [N28E34] decayed slowly and quietly.
S8057 [N23E49] was quiet and stable.
S8059 [N38E02] was quiet and stable.

AR S8055 behind the southwest limb produced a C1.0 flare at 07:03 UT.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.0 12:40   13153 GOES16 simultaneous flare in AR 13156

Coronal mass ejections (CMEs)

December 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 (CH1118) will rotate across the central meridian on December 4-5.

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 active conditions are likely on December 5 becoming quiet on December 6. On December 7-8 quiet to minor storm is expected due to effects from CH1118.

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
13152 2022.11.22
2022.11.23
      N28W79           location: N28W81
S8043 2022.11.27       N25W45            
S8044 2022.11.27       N18W26            
13154 2022.11.29
2022.12.01
  2   S38W46 0003   BXO

location: S38W30

13158 2022.11.30
2022.12.04
6 33 22 N24E06 0020 CRO DRI beta-gamma

location: N25E08

area: 0140

13153 2022.11.30
2022.12.01
13 39 23 S17E33 1080 FKO FKO

location: S16E32

S8051 2022.11.30       N13W38            
13155 2022.12.01
2022.12.01
14 25 13 N23W25 0140 DAI DSI

location: N23W22

13156 2022.12.01
2022.12.02
4 14 4 N25E39 0170 CSO CAO  
S8054 2022.12.01       N28E17            
S8056 2022.12.02   3 1 N28E34 0006   BXO  
S8057 2022.12.02   3 1 N23E49 0010   BXO  
S8058 2022.12.02       S13W38            
S8059 2022.12.03   4   N38E02 0008   AXX  
13157 2022.12.03
2022.12.03
6 17 8 N16E61 0210 DSO EHI

area: 0310

location: N17E59

Total spot count: 43 140 72  
Sunspot number: 93 230 142  (total spot count + 10 * number of spotted regions)
Weighted SN: 71 173 105  (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): 102 127 114  

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) 9.6
2022.12 130.1 (1)   8.9 (2A) / 69.0 (2B) / 86.2 (2C) (107.1 projected, +4.8) (15.8)
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.