[Ips-msgr] IPS Monthly Report - April 03

rwc rwc at ips.gov.au
Mon May 5 09:59:42 EST 2003


SUBJ: IPS MONTHLY SUMMARY - APRIL 2003
ISSUED BY IPS RADIO AND SPACE SERVICES
FROM THE AUSTRALIAN SPACE FORECAST CENTRE

1.     SOLAR-GEOPHYSICAL INDICES

              SOLAR    AUST       AUST
Day      10 cm flux   A-INDEX   T INDEX
01-Apr         153       12       82
02-Apr         158       15       96
03-Apr         156       10       92
04-Apr         153       19       94
05-Apr         137       17       93
06-Apr         126        6       95
07-Apr         116        6      102
08-Apr         112       21       97
09-Apr         109       21       89
10-Apr         103       19       90
11-Apr         103       13       81
12-Apr         102        9       74
13-Apr         102        7       83
14-Apr         102       11       86
15-Apr         101       14       98
16-Apr          99       25       80
17-Apr         101       18       83
18-Apr         108       14       80
19-Apr         112        9       74
20-Apr         119       13       84
21-Apr         126       17      106
22-Apr         132       19      105
23-Apr         133       12       90
24-Apr         128       18       81
25-Apr         144       20       75
26-Apr         144       13       78
27-Apr         154       11       78
28-Apr         152       11      100
29-Apr         155       16       94
30-Apr         154       25      101


          10 CM    SUNSPOT  SUNSPOT  AUST     AUST     No of
          FLUX     NUMBER   NUMBER   A-INDEX  T INDEX  FLARES
          Monthly  Monthly  Yearly   Monthly  Monthly  >M1.0 
Month     Average  Average  Average  Average  Average 
Apr 02     189.5    120.4    110.4     11.2    143.2   17
May 02     178.4    120.8    108.8      8.4    133.0   16
Jun 02     148.8     88.5    106.2      6.2    113.9    4
Jul 02     174.5     99.9    102.7      8.8    108.6   35
Aug 02     184.0    116.4     98.7     11.2    133.5   45
Sep 02     175.9    109.3     94.6      9.8    137.7   12
Oct 02     167.0     97.5     90.5     15.7    119.7   22
Nov 02     168.7     95.0     85.6p    14.5    121.1   11
Dec 02     157.2     81.6     82.1p    13.0    124.5   10
Jan 03     144.0     79.5     79.3p    12.9    111.6    7
Feb 03     125.0     46.2     75.0p    15.7     95.5    3
Mar 03     132.3     61.5     70.2p    15.4     90.9    9
Apr 03     126.5     60.0     66.0p    14.7     88.7   15


               Monthly T indices
       Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec
1992   153   172   155   134    95    80    88    66    68    66    84    90  
1993    74    77    79    63    63    64    62    50    37    40    34    43  
1994    57    41    42    26    15    14    23    18    20    20    20    20  
1995    24    33    23    13     3    11    13    10    13     9    13     7  
1996    12     7     4     2     5     2     3     4     4     3    11    15  
1997    14    11    10     8    11     5     9    17    32    27    28    38  
1998    40    41    43    56    46    56    76    75    86    70    74    93  
1999    94    81    89    77    98   124   124   105    89    92   123   113  
2000   108   120   157   152   129   128   148   139   123   129   135   141  
2001   130   131   135*  123   112*  132   112*  113*  142   151   156*  159* 
2002   169   172   165   137   128   119   111*  127   130   114*  106*  113* 
2003   112*   83*   96*   77^   72^   67^   61^   56^   52^   49^   47^   44^ 
2004    43^   41^   39^   37^   35^   33^   31^   29^   28^   26^   24^   23^ 
2005    21^   20^   19^   17^   16^   15^   14^   13^   12^   11^   10^    9^ 
2006     8^    8^    7^    6^    6^    5^    5^    5^    4^    4^    4^    4^ 
2007     4^    5^    5^    6^    7^    8^    9^   11^   13^   16^   18^   21^ 
2008    25^   28^   32^   36^   41^   45^   50^   54^   59^   64^   68^   73^ 
* = New data. T index may have changed.
^ = IPS predicted T index.

The IPS Monthly T-index is derived from the observed monthly 
median values of foF2 for each hour at up to 40 ionospheric 
stations worldwide.  These records become available from IPS 
stations in Australia very soon after each month, but the 
majority are received up to one year later.  This means that 
the exact observed value of the monthly T-index is not 
available until some months later.
 
The predicted smoothed monthly T-indices are computed by 
using a statistical analysis of the observed monthly T-indices 
for all solar cycles since 1938.  The IPS T-indices may not be 
updated each month but only when sufficient new 
data becomes available.

===============================================================================

2.     FLARES AND SHORT-WAVE FADEOUTS 
DATE             CLASS M    CLASS X     FLARE     FADEOUT POSSIBLE ON
                 FLARES     FLARES      MAX       DAYLIGHT HF CIRCUIT
04 Apr 03	 M1.9               	2019UT
04 Apr 03	 M2.1               	2019UT
09 Apr 03	 M2.5/1F            	2329UT
18 Apr 03	 M1.1               	1958UT
21 Apr 03	 M2.8/1N            	1307UT
23 Apr 03	 M5.1/1N            	0106UT    0039-0115UT
23 Apr 03	 M2.0/1F            	1556UT
24 Apr 03	 M3.3/1N            	1253UT    1245-1303UT
25 Apr 03	 M1.2/SF            	0540UT
26 Apr 03	 M2.1/SF            	0058UT
26 Apr 03	 M2.1/SN            	0306UT
26 Apr 03	 M7.0               	0807UT    0801-0809UT
26 Apr 03	 M2.5               	2340UT
27 Apr 03	 M1.7/SF            	1532UT
29 Apr 03	 M1.1/1F            	0459UT

2.1     Comments on Solar Activity.
Solar activity was predominately low during the first half
of the month. An increase in flare activity was observed
during the second half of the month. Most of these flares
were produced by solar region 338, which appeared in the
north-east solar quadrant on 19 Apr and rotated off disk
on 27 Apr. This region is due back to the north-east limb
of the sun on 11 May. A total of 15 M class flares were observed
for the month, the largest flare for the month was
an impulsive M7.0 on 26 Apr, produced by region 338.

===============================================================================

3.     GEOMAGNETIC DISTURBANCES              (for Australian Region)

DATE                     COMMENTS
04-05 Apr 03:  Mostly unsettled to active. Isolated minor storm periods observed.
08-10 Apr 03:  Mostly unsettled to active. Isolated minor storm periods. A sudden
	       impulse of approx. 20nT observed at 0111UT.
14-25 Apr 03:  Unsettled to active. Minor storm periods 16-17 Apr and 25 Apr.
28-30 Apr 03:  Mostly quiet to active with isolated minor storm periods on 30 Apr.

Coronal hole high speed wind streams produced broad periods of elevated 
geomagnetic activity this month. A weak mass ejection signature was observed 
on 08 Apr super-imposed on coronal hole induced activity.

===============================================================================

4.     IONOSPHERIC DISTURBANCES              (for Australian Region)
   01 Apr 03: Some southern region sites depressed 15-20%
11-12 Apr 03: Some southern region sites depressed 15% from 22UT on 11 Apr
	      to 01UT on 12 Apr.
   14 Apr 03: Degraded comms quality local night hours, southern region.
16-17 Apr 03: Some southern region sites depressed 30% from 21UT on 16 Apr
	      to 02UT on 17 Apr.
   24 Apr 03: Some southern region sites depressed 15%.
   25 Apr 03: Degraded comms quality local night hours, southern region.
   30 Apr 03: Degraded comms quality local night hours, southern region.

Ionospheric MUF depressions this month were mild and confined to the 
southern Aus region. Northern Aus region MUFs remained near to 20% 
above predicted monthly values for most of the month.

===============================================================================

5.     IPS WARNINGS AND ALERTS ISSUED

WARNINGS:
HF RADIO WARNING:
ISSUE DATE      NO       BEGIN           END
08 Apr 03	26	11 Apr 03	12 Apr 03
14 Apr 03	27	16 Apr 03	17 Apr 03
23 Apr 03	28	23 Apr 03	24 Apr 03
24 Apr 03	29	25 Apr 03	26 Apr 03
26 Apr 03	30	26 Apr 03	28 Apr 03
30 Apr 03	31	30 Apr 03	02 May 03


GEOMAGNETIC WARNING:
ISSUE DATE      NO       BEGIN           END
08 Apr 03	10	10 Apr 03	12 Apr 03
14 Apr 03	11	15 Apr 03	17 Apr 03
23 Apr 03	12	23 Apr 03	24 Apr 03
24 Apr 03	13	25 Apr 03	26 Apr 03
26 Apr 03	14	26 Apr 03	28 Apr 03
30 Apr 03	15	30 Apr 03	02 May 03

ALERTS: 
04 Apr 03: Geomagnetic
04 Apr 03: Flare Alert
04 Apr 03: Flare Alert
05 Apr 03: Geomagnetic
08 Apr 03: Geomagnetic
09 Apr 03: Geomagnetic
16 Apr 03: Geomagnetic
17 Apr 03: Geomagnetic
21 Apr 03: Geomagnetic
22 Apr 03: Geomagnetic
23 Apr 03: Flare Alert
23 Apr 03: Geomagnetic
24 Apr 03: Flare Alert
25 Apr 03: Flare Alert
26 Apr 03: Flare Alert
29 Apr 03: Flare Alert
30 Apr 03: Geomagnetic


SWF ALERTS AND DURATION REPORTS
DATE	SWF BEGIN-END (UT)
23 Apr 03: SWF Alert (0059-0129 UT)


IPS Radio and Space Services      | email: asfc at ips.gov.au
PO Box 1386                       | WWW: http://www.ips.gov.au
Haymarket NSW 1240  AUSTRALIA     | FTP: ftp://ftp.ips.gov.au 
tel: +61 2 9213 8010              | fax: +61 2 9213 8060 



More information about the ips-msgr mailing list