Solar Terrestrial Activity Report

Activity chart

Last major update issued on March 10, 2016 at 04:45 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 / 4K (*)
  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 on March 9. Solar wind speed at ACE ranged between 347 and 466 km/s.

Solar flux at 20h UTC on 2.8 GHz was 97.4 (decreasing 15.4 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 103.3. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.5). Three hour interval K indices: 22112112 (planetary), 21222211 (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 10 active regions using 2K resolution (SN: 153) and 7 active regions using 1K resolution (SN: 92) SDO images on the visible solar disk.

Region 12512 [N12W71] decayed and was quiet.
Region 12513 [N10W15] was quiet and stable.
New region 12518 [N05W27] emerged on March 8 and developed slowly on March 9 when it was numbered by SWPC.
New region 12519 [N05E75] rotated into view and produced 2 C flares.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5145 [N08W38] reemerged with a tiny spot.
S5166 [N03W52] decayed slowly and quietly.
S5167 [N15W41] was quiet and stable.
S5170 [N13E56] was quiet and stable.
S5171 [N19E57] was quiet and stable.
New region S5174 [N07W62] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location AR Recorded by Comment
C3.3 12:50 N06E85 12519 GOES15  

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

Coronal mass ejections (CMEs)

March 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 (CH720) was in a potentially geoeffective position on March 7-8. A recurrent extension of the southern polar coronal hole will likely rotate into an Earth facing position on March 11.

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 to fair.

Forecast

The geomagnetic field is expected to be quiet to unsettled on March 10-12. Effects from CH720 could cause active intervals on March 11.

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
12511 2016.02.29
2016.03.02
2     N03W50 0020 CAO      

actual location: N03W34

SWPC switched ARs 12511/12510 on March 3

SWPC then moved the region to the location of AR S5166 on March 8

12512 2016.03.01
2016.03.02
2 1 1 N11W70 0030 HSX HAX

area: 0070

S5145 2016.03.01   1   N08W38 0003   AXX    
12510 2016.03.01
2016.03.02
      N07W38         SWPC switched ARs 12510/12511 on March 3

actual location: N06W45

12513 2016.03.02 1 13 4 N10W17 0040 HSX CSO images/AR_12513_20160309_2345.png images/AR_12513_20160308_2345.png location: N10W15

area: 0090

12515 2016.03.02
2016.03.04
      S03W89            
S5152 2016.03.02       N07W54            
12517 2016.03.03
2016.03.06
      N24W79            
12516 2016.03.03
2016.03.04
      S04W80            
S5156 2016.03.03       S09W47            
12514 2016.03.03
2016.03.04
      N12W83          

 

S5159 2016.03.04       N25W47            
S5161 2016.03.05       S02W39            
S5162 2016.03.05       S15W34            
S5163 2016.03.06       N12W24            
S5165 2016.03.07       S11W59            
S5166 2016.03.07   9 3 N03W52 0030   CRO AR 12511 to SWPC
S5167 2016.03.07   1   N15W41 0001   AXX  
12518 2016.03.08
2016.03.09
5 21 10 N04W29 0030 CAO DRI location: N05W27

area: 0080

S5169 2016.03.08       S08E35          
S5170 2016.03.08   2 2 N13E56 0006   BXO  
S5171 2016.03.08   2   N19E57 0003   BXO  
S5172 2016.03.08       S30W07          
12519 2016.03.09 1 2 1 N06E76 0070 HSX CAO   area: 0130
S5174 2016.03.09   1 1 N07W62 0004   BXO    
Total spot count: 11 53 22  
Sunspot number: 61 153 92  (total spot count + 10 * number of spotted regions)
Weighted SN: 36 74 43  (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): 67 69 74 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 (97.0)   17.9 (2A) / 61.7 (2B) / 70.8 (2C) (54.5 projected, -3.1) (9.7)

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.