Solar Terrestrial Activity Report

Activity chart

Last major update issued on March 7, 2016 at 05:45 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 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 major storm on March 6. Solar wind speed at ACE ranged between 342 and 602 km/s. A high speed stream associated with CH718 arrived during the latter half of the day and caused a stronger than expected disturbance.

Solar flux at 20h UTC on 2.8 GHz was 95.5 (decreasing 19.7 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 103.6. The Potsdam WDC planetary A index was 29 (STAR Ap - based on the mean of three hour interval ap indices: 28.6). Three hour interval K indices: 01222566 (planetary), 11322554 (Boulder).

The background x-ray flux is at the class B1 level.

At the time of counting spots (see image time), spots were observed in 8 active regions using 2K resolution (SN: 139) and 8 active regions using 1K resolution (SN: 108) SDO images on the visible solar disk.

Region 12510 [N06W03] was quiet and stable.
Region 12511 [N03E07] decayed slowly and quietly.
Region 12512 [N12W29] developed significantly as new flux emerged. The region has weak polarity intermixing.
Region 12513 [N11E25] was quiet and stable.
Region 12514 [N13W40] decayed slowly and quietly.
New region 12517 [N25W38] emerged on March 3 and was numbered by SWPC 3 days later.

Spotted regions not numbered (or interpreted differently) by SWPC:
S5145 [N07E05] was quiet and stable.
New region S5163 [N12E15] 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 4-6: 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 trans equatorial coronal hole (CH718) rotated across the central meridian on March 2. A southern hemisphere coronal hole (CH720) will rotate into a potentially geoeffective position on March 7.

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 minor storm on March 7 due to effects from CH718 and quiet to unsettled on March 8 becoming quiet on March 9.

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
12509 2016.02.25
2016.02.29
      N09W70          

 

S5134 2016.02.26       S07W59            
S5140 2016.02.28       S17W35            
12511 2016.02.29
2016.03.02
  8 3 N06W11 0020   BXO

actual location: N03E07

SWPC switched ARs 12511/12510 on March 3

12512 2016.03.01
2016.03.02
7 15 8 N11W30 0030 CAO DAI beta-gamma

area: 0100

S5145 2016.03.01   5 2 N07E05 0020   HRX  
12510 2016.03.01
2016.03.02
4 6 3 N06E03 0020 CRO AXX SWPC switched ARs 12510/12511 on March 3

actual location: N06W03

area: 0014

12513 2016.03.02 1 11 3 N12E23 0050 HSX CSO location: N11E25

area: 0110

12515 2016.03.02
2016.03.04
      S03W42            
S5151 2016.03.02       S14W41            
S5152 2016.03.02       N07W14            
S5153 2016.03.03       N20W27            
12517 2016.03.03
2016.03.06
2 3 3 N24W38 0010 BXO DRO area: 0020
12516 2016.03.03
2016.03.04
      S04W35            
S5156 2016.03.03       S09W08            
12514 2016.03.03
2016.03.04
4 6 4 N14W39 0030 CAO CRO

 

S5158 2016.03.04       N49W24            
S5159 2016.03.04       N25W08            
S5160 2016.03.04       N05W34            
S5161 2016.03.05       S02W00          
S5162 2016.03.05       S15E05         images/AR_S5162_20160305_2345.png  
S5163 2016.03.06   5 2 N12E15 0016   BXO    
Total spot count: 18 59 28  
Sunspot number: 68 139 108  (total spot count + 10 * number of spotted regions)
Weighted SN: 36 78 47  (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): 75 62 86 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 (97.7)   12.4 (2A) / 64.2 (2B) / 76.7 (2C) (54.5 projected, -3.1) (8.8)

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.