Solar Terrestrial Activity Report

Activity chart

Last major update issued on March 5, 2016 at 05:50 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 (March 4, 2016)
Solar cycle Solar cycles 23-24 (March 1, 2016) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (March 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 (March 1, 2016) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12, 13, 14, 16 and 24 (March 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 March 4. Solar wind speed at ACE ranged between 346 and 373 km/s.

Solar flux at 20h UTC on 2.8 GHz was 100.5 (decreasing 16.6 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 103.7. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.0). Three hour interval K indices: 31010000 (planetary), 20012111 (Boulder).

The background x-ray flux is at the class B2 level.

At the time of counting spots (see image time), spots were observed in 15 active regions using 2K resolution (SN: 231) and 11 active regions using 1K resolution (SN: 144) SDO images on the visible solar disk.

Region 12506 [S06W78] decayed slowly and quietly.
Region 12509 [N09W37] was quiet and stable.
Region 12510 [N06E22] was quiet and stable.
Region 12511 [N03E32] gained spots and has polarity intermixing. SWPC includes AR S5145 in this region.
Region 12512 [N11W01] decayed slowly and quietly.
Region 12513 [N11E51] was quiet and stable.
New region 12514 [N14W12] emerged on March 3 and developed further on March 4 when it was numbered by SWPC. The region produced the only C flare of the day.
New region 12515 [S02W16] emerged on March 2 and was numbered by SWPC 2 days later as the region began to decay.
New region 12516 [S03W06] emerged on March 3 and was decaying when it was numbered by SWPC the following day.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5145 [N07E32] was quiet and stable.
S5151 [S14W15] was quiet and stable.
S5154 [N25W11] decayed slowly and quietly.
New region S5158 [N49E02] emerged as a reversed polarities region at a high latitude.
New region S5159 [N25E18] emerged with tiny spots.
New region S5160 [N05W08] emerged with a few spots.

C2+ flares:

Magnitude Peak time (UT) Location AR Recorded by Comment
           

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

Coronal mass ejections (CMEs)

March 2-4: 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 northern hemisphere coronal hole (CH719) was in an Earth facing position on March 1. A trans equatorial coronal hole (CH718) rotated across the central meridian on March 2.

Propagation

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

Forecast

The geomagnetic field is expected to be quiet to active on March 5-6 due to effects from CH718 and CH719 and quiet to unsettled on March 7.

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
12506 2016.02.22
2016.02.24
4 4 2 S06W76 0060 CSO CAO

area: 0110

12509 2016.02.25
2016.02.29
  3   N09W42 0005   AXX

location: N09W37

12508 2016.02.26
2016.02.28
      N06W64            
S5134 2016.02.26       S07W33            
S5138 2016.02.28       N20W48            
S5140 2016.02.28       S17W09            
S5141 2016.02.29       N08W42          
12511 2016.02.29
2016.03.02
  14 7 N06E19 0040   DRI beta-gamma

SWPC count includes AR S5145

actual location: N03E32

SWPC switched ARs 12511/12510 on March 3

S5143 2016.02.29       N24W58            
12512 2016.03.01
2016.03.02
3 6 3 N11W00 0020 CRO CRO area: 0030
S5145 2016.03.01   6 3 N07E32 0025   HRX  
12510 2016.03.01
2016.03.02
3 7 2 N05E30 0030 CRO BXO SWPC switched ARs 12510/12511 on March 3

actual location: N06E22

S5147 2016.03.01       S11W29            
12513 2016.03.02 1 3 1 N12E49 0040 HSX HSX location: N11E51

area: 0110

12515 2016.03.02
2016.03.04
2 1 1 S03W14 0010 BXO AXX area: 0005
S5151 2016.03.02   3   S14W15 0006   BXO  
S5152 2016.03.02       N07E12            
S5153 2016.03.03       N20W01          
S5154 2016.03.03   1   N25W11 0002   AXX  
12516 2016.03.03
2016.03.04
3 2 1 S04W05 0010 BXO AXX area: 0005
S5156 2016.03.03       S09E18          
12514 2016.03.03
2016.03.04
9 24 11 N14W11 0020 CRO DAI beta-gamma

area: 0130

S5158 2016.03.04   1   N49E02 0002   AXX    
S5159 2016.03.04   2 1 N25E18 0004   BXO    
S5160 2016.03.04   4 2 N05W08 0010   CRO    
Total spot count: 25 81 34  
Sunspot number: 95 231 144  (total spot count + 10 * number of spotted regions)
Weighted SN: 23 108 61  (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): 105 104 115 k * (sunspot number)
As of February 19, 2015: k = 1.1 for SWPC, k = 0.45 for MSN 2K, k = 0.80 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
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 66.3 (-1.9) 14.58
2015.09 101.7 102.7 78.1 (66.0 projected, -0.3) 15.78
2015.10 104.1 103.3 61.7 (65.3 projected, -0.7) 14.02
2015.11 109.3 106.9 63.2 (63.2 projected, -2.1) 12.09
2015.12 113.1 109.5 57.7 (61.5 projected, -1.7) 14.29
2016.01 103.4 100.1 56.6 (59.8 projected, -1.7) 9.4
2016.02 103.6 101.0 57.2 (57.4 projected, -2.4) 9.9
2016.03 (98.6)   8.0 (2A) / 62.3 (2B) / 79.6 (2C) (54.5 projected, -3.1) (5.3)

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.