Weekly Bulletin on Solar and Geomagnetic Activity
Highlights on 16 - 22.04.2012,
Forecast on 23 - 30.04.2012,
ëüòòéîçôïîï÷óëéå ïâïòïôù 2122, 2123 (31,93.03, 28,19.04.2012)
 
SUNSPOT ACTIVITY OF THE PAST PERIOD GRADUALLY INCREASED FROM THE AVE-
RAGE TO HIGH AND AGAIN TO AVERAGE OF LEVELS. ESTIMATED, RATING, WEEK-
LY THE AVERAGE OF SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM FOR THE 
PERIOD WAS MADE W=070+27/-21. ON THE VISIBLE DISK OF THE SUN CONSTAN-
TLY THERE  WERE 5 - 6 QUIET SUNSPOT GROUPS FOUR OF WHICH REACHED THE 
AVERAGE SIZE.

NEXT WEEK THE SUNSPOT ACTIVITY IS EXPECTED TO BE LOW. THE CALCULATED 
MOST LIKELY WEEKLY AVERAGE VALUE OF SUNSPOT NUMBER IN THE INTERNATIO-
NAL SYSTEM FOR THE NEXT WEEK W=060+20/-10.

FLARE ACTIVITY AT 16.04 WAS ON THE MIDDLE LEVEL AND THE LOW IN OTHER 
DAYS AT LOW.  BY DATA OF SOHO CORONOGRAPHS FOR THE PERIOD IT WAS OB-
SERVED 49 CORONAL MASS EJECTIONS AMONG  WHICH 4 WERE TYPE  "PARTIAL 
HALO II" (16, 18, 19.04).

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FLARES to   tm    te   c/p local. Class    E(1-8A)  AR   RII/IV  CME
                                  X / opt.  J/m-2
16.04  1724 1745 >1800 n13w85L068 M1.7/BSL 2.5E-2 11461 

DSF     to         te   c/p local.  l in deg. Fl   AR          CME
16.04       1300        S43E33L166      ?                      CME
17.04 >0102 1330 <1339  N24W40L176      17                CME/1424
19.04  1342       1617  S36E71L038      14                CME/1524
c/p local. - central part localization 
--------------------------------------------------------------------

NEXT WEEK FLARE ACTIVITY IS EXPECTED ON LOW AND VERY LOW LEVELS.
 
ON THE VISIBLE SOLAR DISK DURING THE LAST WEEK THE FOLLOWING CORONAL 
HOLES WERE OBSERVED:
---------------------------------------------------------------------
  sign N end   Å end   S end   W end       EE    R   Observatories
CH -  N50L111 N43L093 N40L113 N45L116   23.04   3   KP, SDO, SOHO...
CH -  N27L062 N25L060 N18L072 N23L075   25.04   4   KP, SDO, SOHO...
R - solar rotations; KP - KITT PEAK solar observatory;
EE-date of possible geomag. disturbation in the Earth's environment.
---------------------------------------------------------------------

AFTER 20.04/07 UT THE EARTH WAS IN "+" SECTOR OF THE INTERPLANETARY 
MAGNETIC FIELD. THE FOLLOWING SECTOR BOUNDERY + /- THE EARTH SHOULD 
PASS 23.04.
 
APRIL     16     17     18     19     20     21     22    APRIL
Wus      086    078    096    122    162    147    118    
F10.7    108    114    122    138    142    149    148     
èbcg    B2.7   ÷2.9   B4.0   ÷5.2   ÷3.8   ÷5.4   ÷6.4   GOES
Sp       500    300    590    520   1509   1630   1490 
Nnew      1      2      1      1      1             1              
IMF       -      -      -      -     -/+     +      +    ACE
Å>2   3.6å+8 1.1å+8 7.5E+6 1.1å+7 2.6å+6 6.4å+6 6.0å+9   GOES
Nm%                                                      THULE
Ap       5       8      8      4      8      7      7    áÒ
Dst                                                      ëIOTO
Amsc     9       13     9      8      8     10     11    IZMIRAN
---------------------------------------------------------------

THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT VERY 
HIGH LEVEL OF FLUX WAS OBSERVED 16-17.04.

THE GREATER THAN 2 MeV ELECTRON FLUX AT HIGH LEVEL IS NOT EXPECTED.

THE GEOMAGNETIC CONDITIONS WAS UNSETTLED AND QUIET.

NEXT WEEK ON APRIL 23 PROBABLY GROWTH OF GEOMAGNETIC ACTIVITY AFTER 
ARRIVAL  TO  EARTH THE DISTURBANCE FROM SOLAR FILAMENT EJECTA 19.04 
ACCOMPANIED  BY CME TYPE "PARTIAL GALO II" (ANGULAR WIDTH 103 deg.). 
PROBABILITY OF THE MAGNETIC STORM ON 23.04 ABOUT 60 %. In OTHER DAYS 
THE GEOMAGNETIC CONDITION IS EXPECTED UNSETTLED AND QUIET.

HIGHLIGHT AND FORECAST COMPOSED FROM DATA
OF NOAA SWPC            http://www.sec.noaa.gov,
OF THE SOLAR INFLUENCES DATA ANALYSIS CENTER - 
SIDC, BELGIUM           http://sidc.oma.be/index.php3, 
OF THE IZMIRAN, RUSSIA  http://www.izmiran.ru