Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 3, 2014 at 04:25 UTC.

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

[POES auroral activity level October 2009 - December 2012]
[Solar polar fields vs solar cycles - updated June 4, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet on July 2. Solar wind speed at SOHO ranged between 274 and 306 km/s.

Solar flux at 20h UTC on 2.8 GHz was 169.4 (increasing 58.9 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 134.5. The Potsdam WDC planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.4). Three hour interval K indices: 01111211 (planetary), 11122411 (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 14 active regions using 2K resolution (SN: 344) and 13 active regions using 1K resolution (SN: 251) SDO images on the visible solar disk.

Region 12097 [N17W53] lost the leader spot and gained a trailing penumbra spot.
Region 12100 [N11W12] was mostly quiet and stable.
Region 12102 [N12E17] developed slowly and was mostly quiet.
Region 12103 [S16E08] was quiet and stable.
Region 12104 [S10E27] still has magnetic delta structures in the western part of the southermost penumbra. A major flare remains a possibility.
Region 12105 [S05W15] was quiet and stable.
Region 12106 [N16E34] developed further and could produce M class flares.
Region 12107 [S19E37] lost the magnetic delta structure when a penumbra split into two penumbrae.
Region 12108 [S08E54] developed slowly and quietly.
New region 12109 [S08E75] rotated fully into view and has a large leader spot.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3599 [N04E16] was quiet and stable.
New region S3607 [N12E06] emerged with penumbra spots.
New region S3608 [S16E62] emerged with a few spots.
New region S3609 [S13E40] remerged with penumbra spots.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
       

Coronal mass ejections (CMEs)

June 30 - July 2: 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 trans equatorial coronal hole (CH625) was in an Earth facing position on June 30-July 1. Another trans equatorial coronal hole (CH626) could rotate into an Earth facing position on July 5.

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 poor. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet to unsettled on July 3-4 and quiet on July 5.

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) 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
12096 2014.06.21
2014.06.22
1     N10W66 0010 AXX    

spotless

12097 2014.06.22 1 1   N14W58 0010 AXX AXX  
12100 2014.06.25
2014.06.27
16 27 17 N10W14 0040 CAI DRI

location: N11W12

area: 0080

S3579 2014.06.26       S10W30           plage
12099 2014.06.26
2014.06.27
      S16W75           plage
12103 2014.06.26
2014.06.28
  2 1 S10W04 0006   AXX location: S16E08
S3583 2014.06.27       N00E06           plage
12102 2014.06.27
2014.06.28
15 32 22 N12E17 0070 DSI DAI

area: 0120

12104 2014.06.28 23 40 27 S10E27 0470 DKC DKC beta-gamma-delta

area: 0800

S3587 2014.06.28       S23W32           plage
12107 2014.06.28
2014.06.29
7 23 12 S20E34 0340 DKO DHC area: 0450

location: S19E37

S3590 2014.06.28       S23E23           plage
S3591 2014.06.28       S12E05           plage
S3592 2014.06.28       S11W31           plage
12105 2014.06.28
2014.06.29
1 3 3 S05W12 0010 AXX BXO locaton:S05W12
12106 2014.06.29 9 40 17 N14E34 0070 DAO DAI area: 0280
S3597 2014.06.30       S26W31           plage
12108 2014.06.30
2014.07.01
6 15 8 S09E53 0090 DAO DAI area: 0120
S3599 2014.06.30   3 2 N04E16 0012   AXX  
S3600 2014.06.30       S31W32           plage
S3601 2014.07.01       S29W59         plage
S3602 2014.07.01       S19W30         plage
S3603 2014.07.01       N06W09         plage
S3604 2014.07.01       S10W36         plage
S3605 2014.07.01       N05W31         plage
12109 2014.07.01
2014.07.02
1 8 7 S08E74 0150 HSX DKO area: 0540
S3607 2014.07.01   2 1 N12E06 0007   AXX  
S3608 2014.07.02   3 2 S16E62 0022   DRO    
S3609 2014.07.02   5 2 S13E40 0012   BXO    
Total spot count: 80 204 121  
Sunspot number: 180 344 251  (total spot count + 10 * number of spotted regions)
Weighted SN: 125 255 172  (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): 108 120 138 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
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 73.1 (+4.1) 5.23
2013.10  132.1 131.2 85.6 75.0 (+1.9) 7.71
2013.11  148.3 145.1 77.6 75.4 (+0.4) 5.68
2013.12 147.7 143.1 90.3 76.0 (+0.6) 4.68
2014.01 157.4 152.4 82.0 (76.9 projected, +0.9) 5.44
2014.02 170.3
(cycle peak)
166.3 102.8 (cycle peak) (76.7 projected, -0.2) 10.70
2014.03 149.9 148.5 92.2 (77.1 projected, +0.4) 4.88
2014.04 143.9 144.8 84.7 (76.2 projected, -0.9) 7.88
2014.05 129.7 132.9 75.2 (73.7 projected, -2.5) 5.75
2014.06 122.0 125.8 71.0 (71.0 projected, -2.7) 6.7
2014.07 160.6 (1)   10.8 (2A) / 167 (2B) / 85.3 (2C) (68.3 projected, -2.7) (3.0)

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.