Solar Terrestrial Activity Report

Activity chart

Last major update issued on March 10, 2014 at 05:25 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update March 1, 2014)] [Cycle 24 progress (last update March 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update March 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update March 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update March 1, 2014)]

[POES auroral activity level since October 2009 - updated January 26, 2013]
[Solar polar fields vs solar cycles - updated February 23, 2014]
[Presentation 3rd SSN Workshop, Tucson, 2013 (pdf)]

Recent activity

The geomagnetic field was very quiet on March 9. Solar wind speed at SOHO ranged between 272 and 353 km/s.

Solar flux at 20h UTC on 2.8 GHz was 145.9 (decreasing 15.1 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 154.3. The Potsdam WDC planetary A index was 2 (STAR Ap - based on the mean of three hour interval ap indices: 2.1). Three hour interval K indices: 10000011 (planetary), 10111211 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time) spots were observed in 13 active regions in 2K resolution (SN: 257) and 10 active regions in 1K resolution (SN: 171) SDO images on the visible solar disk.

Region 11991 [S25W71] was quiet and stable.
Region 11996 [N15W35] developed further and has a magnetic delta structure in a central penumbra. Minor M class flares are possible.
Region 11998 [S09E16] was quiet and stable.
Region 11999 [S16W30] was quiet and stable.
Region 12000 [S11E01] decayed slowly and quietly.
Region 12001 [N19W78] was quiet and stable.
Region 12002 [S18E51] developed quickly and has a significant magnetic delta structure centrally. The region was very active during the day.
C5+ flares: C6.5 at 04:48, C7.1 at 13:32, M1.0/1F at 13:58, C7.7 at 14:42, M1.0 at 20:28, C5.2 at 22:42 UTC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3196 [N11E04] reemerged with a penumbra spot.
S3197 [N09W21] was quiet and stable.
S3202 [N25W20] decayed slowly and quietly.
New region S3205 [S08E78] rotated into view.
New region S3206 [N06E03] emerged with a few spots.
New region S3207 [N08W03] emerged with penumbra spots.

Coronal mass ejections (CMEs)

March 7-9: No obviously Earth directed CMEs were observed in LASCO and STEREO 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 small southern hemisphere coronal hole (CH607) was in an Earth facing position on March 9.

Coronal hole map

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 on March 10-11. On March 12-13 there is a chance of a few unsettled intervals due to effects from CH607.

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: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability.

Active solar regions

(Click on image for 2K 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 overlay
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
11990 2014.02.24 1     S12W94 0060 HSX     rotated out of view
11991 2014.02.25
2014.02.26
  2 1 S26W75 0010   BXO

location: S26W71

11993 2014.02.25
2014.02.26
      N17W89           plage
11996 2014.03.01
2014.03.02
19 38 25 N14W37 0080 EAI EAC

beta-gamma-delta

location: N15W35

area: 0200

S3176 2014.03.02       N09W20           plage
S3182 2014.03.02       S12W50           plage
S3186 2014.03.03       N08W51           plage
11999 2014.03.04
2014.03.05
1 4 2 S16W29 0000 AXX BXO area: 0010
11998 2014.03.04
2014.03.05
5 18 10 S09E14 0060 CAO DAO location: S09E16

area: 0130

S3190 2014.03.04       S06W27           plage
S3191 2014.03.04       S24W43           plage
12000 2014.03.05
2014.03.06
7 13 3 S11W00 0010 BXO BXO area: 0030
S3194 2014.03.05       N16W12           plage
12001 2014.03.05
2014.03.06
8 5 3 N19W78 0040 DSO BXO  
S3196 2014.03.07   1   N10W08 0003   AXX    
S3197 2014.03.07   2   N09W21 0006   AXX  
S3198 2014.03.07       S20W41           plage
S3199 2014.03.07       S27W08           plage
12002 2014.03.07
2014.03.08
12 30 19 S19E51 0090 DAC DAC beta-gamma-delta

area: 0400

S3202 2014.03.08   2   N25W20        
S3203 2014.03.08       N01W35         plage
S3204 2014.03.08       S01E30         plage
S3205 2014.03.09   4 3 S08E78 0030   DRO    
S3206 2014.03.09
2014.03.10
  5 3 N06E03 0030   DRO    
S3207 2014.03.09   3 2 N08W03 0010   BXO    
Total spot count: 53 127 71  
Sunspot number: 123 257 171  (total spot count + 10 * number of spotted regions)
Weighted SN: 78 148 92  (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): 74 90 94 k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for MSN 2K, k = 0.55 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number Average ap
(3)
Measured 1 AU
2012.11 121.3 118.3 61.8 59.7 (+1.1) 7.08
2012.12 108.6 105.0 40.8 59.6 (-0.1) 3.44
2013.01 127.1 123.1 62.9 58.7 (-0.9) 4.69
2013.02 104.3 101.8 38.0 58.4 (-0.3) 6.11
2013.03 111.3 110.2 57.9 57.5 (-0.9) 10.56
2013.04 124.8 125.9 72.4 57.9 (+0.4) 5.40
2013.05 131.4 134.3 78.7 59.9 (+2.0) 9.73
2013.06 110.1 113.7 52.5 62.6 (+2.7) 12.60
2013.07 115.5 119.3 57.0 65.5 (+2.9) 9.47
2013.08 114.6 118.3 66.0 69.0 (+3.5) 8.27
2013.09 102.6 103.7 36.9 (72.8 projected, +3.8) 5.23
2013.10  132.1 131.2 85.6 (73.8 projected, +1.0) 7.71
2013.11  148.3 145.1 77.6 (72.7 projected, -1.1) 5.68
2013.12 147.7 143.1 90.3 (71.6 projected, -1.1) 4.68
2014.01 157.4 152.4 82.0 (71.6 projected, 0.0) 5.44
2014.02 170.3
(cycle peak)
166.3 102.8 (cycle peak) (70.9 projected, -0.7) 10.70
2014.03 153.1 (1)   47.4 (2A) / 163.3 (2B) / 121.6 (2C) (71.0 projected, +0.1) (4.0)

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). The official WDC-SILSO international sunspot number is typically 30-50% lower. 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.

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 the UTC day. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.