Division V - Working Group 8 met 7 August in Uppsala, Sweden.
The following topics were discussed:
- Chairman's Report (copy not yet available)
- New Surveys and Charts
- Reporting of magnetic repeat station data - a
new record sheet was distributed
- Catalog of Regional Magnetic Repeat Station surveys was published 2 years
ago. The group decided that an electronic update to the catalog will suffice. This
may be done by the WDC for Solid Earth Geophysics, Boulder with the groups help
- IAGA Guide for Magnetic Repeat Station Surveys was published by Newitt, Barton,
Bitterly. IAGA published with advertisements to offset costs. Free copies were given to
people who contributed data. Contact the Secretary-General, Prof. Bengt Hultqvist, of IAGA in order to purchase it.
- IGRF Publications
- Publication of the 7th generation IGRF by JGG.
- IGRF software and chart package produced by C. Barton in lieu of charts.
Packages sent to observatories and contributors. Also available on-line from
the WG V-8 Home.
- Revision of the IGRF for 2000
- When: Will be approved in 1999 for use on Jan. 1, 2000.
- How: Send models to C. Barton by Jan. 31, 1999. He will
circulate by Feb., 1999. We will decide on model at IUGG in August,
- Frank Lowes will write on-line sections on accuracy.
- Susan McLean will do abstracts, references.
- Degree/order not specified but only 10/8 will be included.
British Geol. Survey, Russian (IZMIRAN) and
NASA/Denmark groups indicated intent to contribute models.
Models to be decided on are a Main field model for epoch
2000 and an SV model for 2000-2005.
- General Business
- IGRF Needs Analysis (McLean).
- Survey sent to 440 people.
- Overall response rate: 10%,
- Greatest weakness of IGRF:
Timeliness of new models (39%), Documentation (15%), Accuracy (15%);
- Greatest strengths of IGRF: International Standard and Coverage, Ease of use,
- What accuracy do you expect from IGRF: Within 30 minutes for D.
- Global Geomagnetic Field Variation (Papitashvilli)
- WWW Page for WG V-8 - Susan McLean, WDC Boulder will do.
- Session topics for Birmingham, 1999
- Near Earth Magnetic Reference Field Models T. Sabaka (US), J. Miquel Torta (Italy)
- International Decade of Geopotential Field Research
- Observatories and Surveys
- IGRF Issues
- Continuous (C) IGRF.
Some people felt adopting a C-IGRF would be confusing. Also some discussion on who
would use the model (Jackson). The group, by a vote, did not consider a C-IGRF
needed at this time.
- Should we extend the IGRF to n=14. No
- Should we update more frequently (4 years) No
- Should we work on Pre-1900 IGRF No
- Should we include External terms No
- Papitashvilli discussed his polar variation model
International Decade for Geopotential Field Research (approved)