Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 14, 2014 at 05:05 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 July 5, 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 13. Solar wind speed at SOHO ranged between 305 and 390 km/s.

Solar flux at 20h UTC on 2.8 GHz was 126.8 (increasing 10.0 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 140.0. The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 4.9). Three hour interval K indices: 22121112 (planetary), 12232322 (Boulder).

The background x-ray flux is at the class B4 level.

At the time of counting spots (see image time), spots were observed in 7 active regions using 2K resolution (SN: 159) and 6 active regions using 1K resolution (SN: 108) SDO images on the visible solar disk.

Region 12109 [S08W73] displayed no significant changes.
Region 12111 [N06W58] decayed quickly losing all trailing spots.
Region 12113 [N07W16] merged with AR 12117. The region has polarity intermixing and C flares are possible.
Region 12114 [S20E02] was quiet and stable.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3637 [S12W63] was quiet and stable.
New region S3638 [N19W03] emerged with a penumbra spot.
New region S3639 [S31W12] was observed with a penumbra spot.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
C6.4/1F 09:03 S08W61 12109

Coronal mass ejections (CMEs)

July 11-13: 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

No signficant coronal holes are currently in or near Earth facing positions.

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

Forecast

The geomagnetic field is expected to be quiet on July 14-17.

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
12108 2014.06.30
2014.07.01
9     S07W89 0200 EAI    

rotated out of view

12109 2014.07.01
2014.07.02
9 7 4 S08W72 0310 DHO CKO

area: 0700

12110 2014.07.02
2014.07.03
      S15W89           plage
12111 2014.07.03
2014.07.04
5 5 3 N06W57 0020 CAO AXX  
S3614 2014.07.04       N06W44           plage
S3618 2014.07.05       N18W51           plage
12113 2014.07.06 9 36 24 N07W18 0070 EAO DRI

beta-gamma

merged with AR 12117

location: N07W16

S3622 2014.07.06       S25W51           plage
12114 2014.07.07
2014.07.08
8 37 15 S20W00 0050 CAO DRI  
12116 2014.07.08
2014.07.10
      S28E04           plage
S3631 2014.07.08       S15W03           plage
S3632 2014.07.08       S16W37           plage
S3633 2014.07.08       N15W32           plage
12117 2014.07.11 2     N08W09 0010 BXO     merged with AR 12113
S3637 2014.07.12   2   S12W63 0003   BXO  
S3638 2014.07.13   1 1 N19W03 0008   AXX    
S3639 2014.07.13   1 1 S31W12 0003   AXX    
Total spot count: 42 89 48  
Sunspot number: 102 159 108  (total spot count + 10 * number of spotted regions)
Weighted SN: 72 105 64  (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): 61 56 59 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 81.8 (78.2 projected, +2.2) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) (79.7 projected, +1.5) 10.70
2014.03 149.9 148.5 91.9 (80.5 projected, +0.8) 4.88
2014.04 143.9 144.8 84.7 (79.7 projected, -0.8) 7.88
2014.05 129.7 132.9 75.2 (77.1 projected, -2.6) 5.75
2014.06 122.0 125.8 71.0 (74.5 projected, -2.6) 6.72
2014.07 176.5 (1)   75.5 (2A) / 180.0 (2B) / 94.4 (2C) (71.5 projected, -3.0) (4.8)

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). 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.