Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 10, 2016 at 04:30 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data from 2003.01 (February 1, 2016)
Solar cycle Solar cycles 23-24 (February 1, 2016) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (February 1, 2016) Noon SDO sunspot count 1K Reference: 4K (large file) (*)
  Solar cycles 1-24 (July 17, 2015) POES auroral activity level October 2009 - December 2012
  Comparison of cycles 21, 22, 23 and 24 (February 1, 2016) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12, 13, 14, 16 and 24 (February 1, 2016) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (January 29, 2016)  

Recent activity

The geomagnetic field was quiet to unsettled on February 9. Solar wind speed at SOHO ranged between 345 and 435 km/s.

Solar flux at 20h UTC on 2.8 GHz was 117.3 (increasing 13.2 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 105.2. The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 7.1). Three hour interval K indices: 21132112 (planetary), 21233322 (Boulder).

The background x-ray flux is at the class B3 level.

At the time of counting spots (see image time), spots were observed in 10 active regions using 2K resolution (SN: 221) and 9 active regions using 1K resolution (SN: 149) SDO images on the visible solar disk.

Region 12492 [N14W27] decayed slowly and quietly.
Region 12494 [S11W54] decayed slowly and quietly.
Region 12496 [N08E06] was quiet and stable.
Region 12497 [N12E23] developed and has a weak magnetic delta in a central southern penumbra. A minor M class flare is possible.
New region 12498 [N18E58] rotated into view on February 8 and was numbered by SWPC the next day.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5080 [N07W17] was quiet and stable.
S5082 [N13E01] was quiet and stable.
S5086 [S12E07] was quiet and stable.
S5091 [N13W35] displayed signs of decay and was quiet.
New region S5096 [N20W17] was observed with tiny spots.

A long duration C1.6 event peaking at 06:57 UT was associated with a filament eruption in and near AR 12491. A CME was observed, the CME probably didn't have any Earth directed components.

C2+ flares:

Magnitude Peak time (UT) Location AR Recorded by Comment
           

Flare activity (SDO/EVE/ESP XRS-B proxy)

Coronal mass ejections (CMEs)

February 7-9: 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 southern hemisphere coronal hole (CH714) rotated across the central meridian on February 8.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet to unsettled on February 10. On February 11-12 effects from CH714 could cause unsettled and active intervals.

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 numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. 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.

Active region Date numbered
detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlays
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12491 2016.01.30
2016.01.31
      N01W54          
12492 2016.02.01
2016.02.02
4 8 4 N14W35 0030 DAO BXO location: N14W27

SWPC is mixing data from two separate ARs

area: 0020

12494 2016.02.03
2016.02.04
6 19 6 S12W57 0120 DAO DAO

 

S5076 2016.02.03       N16W58            
S5080 2016.02.03   3   N07W17 0007   BXO  
12496 2016.02.04
2016.02.05
2 18 7 N08E05 0010 BXO CRO area: 0035
S5082 2016.02.04   6 2 N13E01 0012   BXO  
12497 2016.02.05
2016.02.06
14 48 32 N13E22 0180 DAI EAC beta-gamma-delta

area: 0340

S5085 2016.02.05       N14W50            
S5086 2016.02.05   2 1 S12E07 0005   AXX  
S5087 2016.02.05       S05W59            
S5088 2016.02.05       N23W52            
S5090 2016.02.06       S19W21            
S5091 2016.02.06   9 3 N13W35 0035   DRO  
S5092 2016.02.07       N18W18            
12498 2016.02.08
2016.02.09
3 3 3 N19E58 0010 BXO CRO  
S5094 2016.02.08       N18E24          
S5095 2016.02.08       S10W31          
S5096 2016.02.09   5 1 N20W17 0010   BXO    
Total spot count: 29 121 59  
Sunspot number: 79 221 149  (total spot count + 10 * number of spotted regions)
Weighted SN: 44 140 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): 87 122 127 k * (sunspot number)
As of July 1, 2015: k = 1.1 for SWPC, k = 0.55 for MSN 2K, k = 0.85 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO) (4)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (cycle peak) 110.5 (+1.2) 10.70
2014.04 143.9 144.8 112.5 116.4 (+2.1) (solar max) 7.88
2014.12 158.7 153.8 112.9 92.2 (-2.5) 11.24
2015.01 141.9 137.3 93.0 89.3 (-2.9) 9.46
2015.02 129.1 126.0 66.7 86.1 (-3.2) 9.92
2015.03 125.9 124.6 54.5 82.2 (-3.9) 16.14
2015.04 128.8 129.7 75.3 78.8 (-3.4) 10.73
2015.05 120.0 122.6 88.8 76.0 (-2.8) 8.29
2015.06 122.3 126.1 66.5 72.0 (-4.0) 13.15
2015.07 107.0 110.8 66.4 68.2 (-3.8) 8.83
2015.08 105.4 108.0 64.6 (66.1 projected, -2.1) 14.58
2015.09 101.7 102.7 78.1 (66.1 projected, +0.0) 15.78
2015.10 104.1 103.3 61.7 (65.7 projected, -0.4) 14.02
2015.11 109.3 106.9 63.2 (63.6 projected, -2.1) 12.09
2015.12 113.1 109.5 57.7 (61.9 projected, -1.7) 14.29
2016.01 103.4 100.2 56.6 (60.2 projected, -1.7) 10.0
2016.02 113.8   24.0 (2A) / 77.3 (2B) / 85.1 (2C) (57.8 projected, -2.4) (8.1)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
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) Updated to new data set from WDC-SILSO on July 1, 2015

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.