1 / 18

November 2004 Storms – Australian experiences

November 2004 Storms – Australian experiences. By Phil Wilkinson, Garth Patterson and Patrick Phelan IPS Radio and Space Services Dept Industry, Tourism and Resources P O Box 1386, Haymarket NSW 1240 AUSTRALIA. November 2004 Storm - Solar. Forecasts HF warnings for fadeouts were current

tori
Download Presentation

November 2004 Storms – Australian experiences

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. November 2004 Storms – Australian experiences By Phil Wilkinson, Garth Patterson and Patrick Phelan IPS Radio and Space Services Dept Industry, Tourism and Resources P O Box 1386, Haymarket NSW 1240 AUSTRALIA

  2. November 2004 Storm - Solar • Forecasts • HF warnings for fadeouts were current • Region development meant there was always a potential for a major flare. • Alerts • Proton alert issued 7 Nov, and the PCA continued until 13 Nov. • Effects • M class flares Nov 3, 6 (with partial halo CME);X2 class flares Nov 7 (full halo, Type II/IV), 10 (Type II/IV). • Fadeouts occurred, but were not severe • PCA prevented HF equipment working in Antarctica • HF absorption observed at Hobart late afternoon 8th November • Coincident with northern hemisphere auroral sightings

  3. November 2004 Storm – Mag-1 • Forecasts • Geomagnetic warnings current for period. • Initial (Nov 8) severity of storm not anticipated, • Ap = 60 expected, Ap = 189 observed. • Forecast based on M class flares Nov 5/6, plus weak halo CME • Was this the source of the disturbance on Nov 8? • Subsequent (Nov 10) storm expected, but severity under-estimated • X2 on 7th Nov expected to contribute further activity • Was this the source of renewed activity 10-11 Nov • and mid-latitude aurora? • and later development (Nov 11-12) over-estimated, • X2/3B flare considered a potential risk for increased activity • Parallel ribbon flare; Castell U, 3B for both Learmonth and Culgoora, all suggested this cold produce a major geophysical event, BUT IT DIDN’T. • Was the SI on 11th related to this event? The associated Bz > 0. • Alerts • Several auroral alerts issued (7 – 11 Nov, 2004), some to low latitudes (10 Nov). • Geomagnetic sudden impulses (SI) (Nov 7, 1 SI & Nov 9, 2 SI. Nov 11 1 SI) detected and alerts issued automatically.

  4. November 2004 Storm – Mag-2 • Effects • Large positive and negative bays observed across Australia • At low latitudes these caused significant currents to flow in gas pipelines (being investigated). • Saturated IPS PC variometer array • Auroral sightings (23 email messages) across much of southern Australia, Europe (1) and northern USA • Nov 7, 09 – 11 UT, Sidings Springs and Western Australia, Europe, USA. • Nov 10, 08 – 1230 UT, Bathurst, Dunedin, Hobart. • Several pictures were provided • A collection of southern aurora pictures can be found at http://homepage.mac.com/stevoss/Menu8.html

  5. November 2004 Storm – Mag - 3

  6. November 2004 Storm – Mag - 4 • Aurora – Siding Springs Observatory, NSW, 8th November (0950 - 1030 UT) • Credit: Gordon Garradd (http://members.ozemail.com.au/~loomberah)

  7. November 2004 Storm – Mag - 5 • Aurora – Bathurst, NSW – observed for 10 minutes, 10th November (1047 – 1057 UT) • Credit: Ray Pickard, Bathurst Observatory (http://www.bathurstobservatory.com.au)

  8. November 2004 Storm – Solar wind-1 • Alerts • Solar wind shocks and geomagnetic Sudden Impulses are automatically detected and alerts issued. • Solar wind shocks (7 Nov, 3 shocks; Nov 9, 2 shocks), • and geomagnetic sudden impulses (SI) (Nov 7, 1 SI & Nov 9, 2 SI. Nov 11 1 SI). • All events detected automatically and alerts issued.

  9. November 2004 Storm – Solar wind-2 • Solar wind Interplanetary Field: November 3 – 14, 2004 • Source: SEC (composite image) http://www.sec.noaa.gov/Data/solar.html

  10. November 2004 Storm – Solar wind-3 • Solar wind particle fluxes: November 3 – 14, 2004 • Source: SEC (composite image) http://www.sec.noaa.gov/Data/solar.html

  11. November 2004 Storm – Ionosphere - 1 • Forecasts • HF warnings current for storm period, • Duration of storm not correct • Allowing for possible increased activity • Effects • Maximum Useable Frequencies (MUF) depressed 7 Nov. • Due to large height rises rather than depressed peak densities. • Greater ionospheric variability • Than usually experienced during large storms • Large ionisation gradients across Australia • Hemispheric differences • Southern (summer) hemisphere affected more than northern (winter) hemisphere (note indices).

  12. November 2004 Storm – Ionosphere - 2

  13. November 2004 Storm – Ionosphere - 3

  14. November 2004 Storm – Ionosphere - 4

  15. November 2004 Storm – Media - 1 • Press release • Prepared for release Nov 8, released Nov 9 • Delay unavoidable, but ultimately useful • Considerable interest, especially the prospect of observing aurora • Press • Coverage in local newspapers, including auroral pictures from event • Also on some media websites • Radio • Featured on prime news bulletins and drive time • TV • One TV interview used.

  16. November 2004 Storm – Media - 2 • Aurora – observed Thursday 11th November, near Hobart • Credit: Hobart mercury, November 11th or 12th, 2004

  17. November 2004 Storm – Timeline

  18. November 2004 Storm – Summary • Forecasts: • Warnings for fadeouts and geomagnetic activity were current for the storm period • Severity of storm was not correctly forecast • Duration of geomagnetic and ionospheric storm not correctly forecast • Partly because a third storm, predicted for 11th November, did not eventuate. • Alerts: • Auroral alerts for the period were reasonably helpful for observers (see timeline) • Effects: • Australasian ionosphere severely disturbed • Major gradients and significantly increased spatial variability • Severe geomagnetic disturbances observed • Caused extreme current flows in low latitude gas pipeline • Aurora • Wide observations of active displays • Media • Good media interest, especially in the potential for auroral observations

More Related