[Ips-dsgr] IPS Daily Report - 21 December 02
rwc
rwc at ips.gov.au
Sun Dec 22 09:09:41 EST 2002
SUBJ: IPS DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 21/2330Z DECEMBER 2002 BY IPS RADIO AND SPACE SERVICES
FROM THE AUSTRALIAN SPACE FORECAST CENTRE
SUMMARY FOR 21 DECEMBER AND FORECAST FOR 22 DECEMBER - 24 DECEMBER
STATUS INDICATORS SOL:** YELLOW ** MAG:** RED ** ION: ** YELLOW **
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1A. SOLAR SUMMARY
Activity 21 Dec: Low
Flares: none.
Observed 10.7 cm flux/Equivalent Sunspot Number for 21 Dec: 184/137
1B. SOLAR FORECAST
22 Dec 23 Dec 24 Dec
Activity Moderate Moderate Moderate
Fadeouts Possible Possible Possible
10.7cm/SSN 185/138 180/133 180/133
COMMENT: Solar wind speed decline from 550 to 400km/sec as the
Earth left the coronal hole wind stream. The north-south component
of the interplanetary magnetic field was moderately southward
(10nT) 00-03UT, then briefly swung northward, before becoming
neutral. A shock is expected in the solar wind later today, this
may be followed by a weaker shock on 23 Dec. Solar region 226
(south-west quadrant) and 230 (southeast quadrant) have M class
flare potential. Solar regions 223 and 225 are showing decay.
Another coronal hole is visible in the eastern solar hemisphere
in SOHO EIT 284 imagery. This is an isolated equatorial coronal
hole. Its equatorial location means it will probably be geoeffective,
but is not yet at geoeffective longitude. The appearance of coronal
holes on the Sun has increased in recent months and is generally
considered a feature of the declining phase of a solar cycle.
ACE EPAM data indicates an energetic ion enhancement event beginning
21/1245UT, which can be a precursor to increased geomagnetic
activity over next 24-36 hours.
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2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 21 Dec: Quiet to Major Storm
Estimated Indices 21 Dec : A K
Australian Region 23 4632 3321
Darwin 18 4532 3222
Townsville 17 3532 3321
Learmonth 22 5532 3321
Canberra 23 4632 3321
Hobart 23 4632 3321
Casey(Ant) 25 3653 2221
Observed Regional daily pc3 Indices 21 DEC :
Townsville 2 (Quiet)
Learmonth 9 (Quiet)
Canberra 46 (Unsettled)
Hobart 60 (Unsettled)
Pc3 pulsations are high frequency (10-45 second period) variations
of the Earths magnetic field. Daily pc3 indices are the daily sum
of 20 minute pc3 indices for that station.
Estimated AFr/Ap Indices 21 Dec : A
Fredericksburg 15
Planetary 18
Observed AFr/Ap Indices 20 Dec : A K
Fredericksburg 12
Planetary 16 3423 3334
2B. MAGNETIC FORECAST
Date Ap Conditions
22 Dec 50 Minor to major storm expected later today.
23 Dec 25 Active to minor storm.
24 Dec 13 Unsettled
COMMENT: IPS Geomagnetic Warning 45 was issued on 20 December
and is current for interval 21-22 December. Isolated major storm
period observed early in UT in association with southward Bz.
Field then beacame quiet. Activity believed associated with exit
from coronal hole wind stream. Further storm activity is expected
later today and possibly tomorrow due to recent coronal mass
ejection activity.
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3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
21 Dec Normal Normal-fair Fair
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
22 Dec Normal-fair Normal-poor Normal-poor
23 Dec Normal Poor-fair Poor-fair
24 Dec Normal Normal-fair Normal-fair
COMMENT: Degraded HF conditions observed at mid to high latitudes
early in UT day. Conditions expected to be initially good today
then deteriorating. A stronger degradation is likely on 22-23
Dec due to recent mass ejection activity.
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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
21 Dec 122
Observed Australian Regional MUFs
Equatorial PNG Region:
No data.
Northern Australian Region:
Enhanced by 15% during local day,
Near predicted monthly values during local night.
Southern Australian and New Zealand Region:
Near predicted monthly values during local day,
Enhanced by 15% during local night.
Antarctic Region (Casey/Scott Base):
Near predicted monthly values over the UT day.
Predicted Monthly T index for December: 90
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
22 Dec 120 Initially enhanced 10-20% then depressed 15%
late in UT day.
23 Dec 50 depressed 10 to 20%/near predicted monthly values
24 Dec 80 depressed 10 to 15%/near predicted monthly values
COMMENT: IPS HF Communications Warning 79 was issued on 21 December
and is current for interval 22-23 December. Isolated shortwave
fadeout activity expected. Expected depressed MUFs after local
dawn did not eventuate as geomagnetic activity switched off when
Bz swung northward. Depressed/degraded conditions are likely
late 22-23 Dec following anticipated coronal mass ejection geomagnetic
activity.
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5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 20 Dec
Daily Proton Fluence >1 MeV: 2.5E+06
Daily Proton Fluence >10 MeV: 1.2E+05
Daily Electron Fluence >2 MeV: 1.20E+06 (normal)
X-ray background: C1.0
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
ACE Satellite Solar Wind Day Averaged Data for 20 Dec
Speed: NA km/sec Density: NA p/cc Temp: NA K Bz: NA nT
(Courtesy Space Environment Center, Boulder USA)
ACE data can be incorrect during strong proton events.
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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
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