Open-file Report no.614

GSJ Open-File Report, no. 614

Calculation of the International Geomagnetic Reference Field (5)

Tadashi Nakatsuka (Institute of Geology and Geoinformation, GSJ/AIST)

Abstract

International Geomagnetic Reference Field (IGRF) is a mathematical model of the geomagnetic field originating from the Earth's interior, and it has been adopted at the meeting of the International Association of Geomagnetism and Aeronomy (IAGA).

This Open-File Report has been revised as follows.

(5)	GSJ Open-File Report, no.614 (this issue)	2015	Follow up IGRF-12 generation. Updated C source code with improved calculation accuracy in polar regions. (CD-ROM disk)
(4)	GSJ Open-File Report, no.423	2005	Follow up IGRF-10 generation, WGS84 ellipsoid. (3.5" diskette)
(3)	GSJ Open-File Report, no.402	2004	Follow up 1992 - 2003 revisions of IGRF models. Program update for calculating by generation number, also with C language source. (3.5" diskette)
(2)	GSJ Open-File Report, no.184	1992	Follow up 1987 - 1991 revisions of IGRF models. Stored in an electronic media. (5" diskette)
(1)	GSJ Open-File Report, no.27	1986	1st edition. Explanation of IGRF adoption history till 1985. FORTRAN code for IGRF calculation. (only on sheet paper)

The history of the adoption of IGRF models are summarized as follows.

Date	Place (Assembly)	Adoption	Time Span
Oct., 1968	Washington (IAGA Symp.)	1st Generation: IGRF1965	1955-1972
Sept., 1973	Kyoto (IAGA)	Apply IGRF1965 until 1975	1955-1975
Sept., 1975	Grenoble (IUGG)	2nd Generation: IGRF1975	1955-1980
Aug., 1981	Edinburgh (IAGA)	3rd Generation: IGRF1980 Notion of DGRF/PGRF: DGRF1965-1975	1965-1985
Aug., 1985	Prague (IAGA)	4th Generation: IGRF1985, DGRF1980 Non-definitive models IGRF1945-1960	1945-1990
Aug., 1987	Vancouver (IUGG)	5th Generation: definitive models DGRF1945-1960	1945-1990
Aug., 1991	Vienna (IUGG)	6th Generation: IGRF1990, DGRF1985	1945-1995
Sept., 1995	Boulder (IUGG)	7th Generation: IGRF1995, DGRF1990 Non-definitive models IGRF1900-IGRF1940	1900-2000
July, 1999	Birmingham (IUGG)	Set up Task Force	do.
Dec., 1999	(Task Force)	8th Generation: IGRF2000	1900-2005
Aug., 2001	Hanoi (IAGA/IASPEI)	DGRF1995 and DGRF2000 are to be discussed at Sapporo in 2003	do.
July, 2003	Sapporo (IUGG)	9th Generation: IGRF-9 (DGRF1995, DGRF2000, predictive secular term) Notation by generation (e.g., IGRF-8 1997.5)	1900-2005
Dec., 2004	(Task Force)	10th Generation: IGRF-10	1900-2010
Dec., 2009	(Task Force)	11th Generation: IGRF-11	1900-2015
Dec., 2014	(Task Force)	12th Generation: IGRF-12	1900-2020

The text of this report consists of the following sections in Japanese.

    1. Introduction
    2. Outline of IGRF - its history of adoption
    3. Basic formulation for IGRF
    4. Algorithm of calculation
    5. Functions of the subprogram presented
    6. Supplemental information on the subprogram
    7. How to use (example)
    References (in chronological order)
    List of content in appended CD-ROM media

List of content in appended CD-ROM media.

Filename		Format	Content
openfile0614.html		HTML Document	Manuscript for Introduction Web page (mainly in Japanese)
no0614/		Subfolder containing the files below
	igrf.5.pdf	PDF Document	Body text of this open-file report (in Japanese)
	igrf.c	Simple text	Source code of C language subprogram
	igrf01.coef	Simple text	Gauss coefficients data files of the 1st-12th generation IGRF (Header lines are added to the files published by IAGA, to facilitate the input to the program described in this report.)
	igrf02.coef
	igrf03.coef
	igrf04.coef
	igrf05.coef
	igrf06.coef
	igrf07.coef
	igrf08.coef
	igrf09.coef
	igrf10.coef
	igrf11.coef
	igrf12.coef
	index.html	HTML Document	English abstract of this Open-file Report (This document)
	indexJ.html	HTML Document	Japanese abstract of this Open-file Report

References (in chronological order)

Chapman, S. and J. Bartels (1940) Spherical harmonic analysis in geophysics. Geomagnetism, vol.2, 606-638. Oxford Univ. Press, New York.
International Astronomical Union (IAU) (1966) Proceedings of the Twelfth General Assembly, Hanburg, Germany. Trans. IAU, 12B, 594-595.
IAGA Commision 2 Working Group No.4, Analysis of the Geomagnetic Field (1969) The International Geomagnetic Reference Field 1965.0, J. Geomag. Geoelectr., 21, 569-571; J. Geophys. Res., 74, 4407-4408.
International Association of Geomagnetism and Aeronomy (IAGA) (1973) Transactions of the Second General Scientific Assembly, Kyoto, Japan. IAGA Bull., no.35, 147, Resolution 18.
IAGA Division I Study Group, Geomagnetic Reference Fields (1975) International Geomagnetic Reference Field 1975. J. Geomag. Geoelectr., 27, 437-439; Eos Trans. AGU, 57, 120-121 (1976); J. Geophys. Res., 81, 5163-5164 (1976); Geophys. J. Roy. Astron. Soc., 44, 733-734 (1976).
Peddie, N. W. (1981) International Geomagnetic Reference Field 1980: a report by IAGA Division I Working Group 1. J. Geomag. Geoelectr., 33, 607-611; Geophys. J. Roy. Astron. Soc., 68, 265-268 (1982); Geophysics, 47, 841-842 (1982).
IAGA Division 1 Working Group 1 (1981) International Geomagnetic Reference Fields: DGRF 1965, DGRF 1970, DGRF 1975, and IGRF 1980. Eos Trans. AGU, 62, 1169.
Peddie, N. W. (1982) International Geomagnetic Reference Field: the third generation. J. Geomag. Geoelectr., 34, 309-326.
Peddie, N. W. (1983) International Geomagnetic Reference Field - its evolution and the difference in total field intensity between new and old models for 1965-1980. Geophisics, 48, 1691-1696.
IAGA Division I Working Group 1 (1985) International Geomagnetic Reference Field Revision 1985. J. Geomag. Geoelectr., 37, 1157-1163; IAGA News, no.24, 60-64; Pure Appl. Geophys., 123, 641-645; Eos Trans. AGU, 67, 523-524 (1986); Geophys. J. Roy. Astron. Soc., 85, 217-220 (1986); Geophysics, 51, 1020-1023 (1986).
Nakatsuka, T. (1986) Calculation of the International Geomagnetic Reference Field. GSJ Open-File Report, no.27, 25p., Geol. Surv. Japan (in Japanese).
Barraclough, D. R. (1987) International Geomagnetic Reference Field: the fourth generation. Phys. Earth Planet. Interior, 48, 279-292.
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IAGA Division V Working Group 8 : Analysis of the Main Field and Secular Variation (1991) International Geomagnetic Reference Field, 1991 Revision. J. Geomag. Geoelectr., 43, 1007-1012; IAGA News, no.30, 69-76; Pure Appl. Geophys., 137, 301-308; Eos Trans. AGU, 73, 182 (1992); Geophys. J. Int., 108, 945-946 (1992); Geophysics, 57, 956-959 (1992); Phys. Earth Planet. Inter., 70, 1-6 (1992).
Langel, R. A. (1992) International Geomagnetic Reference Field: the sixth generation. J. Geomag. Geoelectr., 44, 679-707.
Nakatsuka, T. (1992) Calculation of the International Geomagnetic Reference Field (2). GSJ Open-File Report, no.184, 27p. + 1 diskette, Geol. Surv. Japan (in Japanese).
IAGA Division V Working Group 8 (1995) International Geomagnetic Reference Field, 1995 Revision. J. Geomag. Geoelectr., 47, 1257-1261; Geophys. J. Int., 125, 318-321 (1996); Phys. Earth Planet. Inter., 97, 23-26 (1996); Pure Appl. Geophys., 147, 195-202 (1996).
Barton, C. E. (1997) International Geomagnetic Reference Field: the seventh generation. J. Geomag. Geoelectr., 49, 123-148.
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Mandea, M. and S. Macmillan (2000) International Geomagnetic Reference Field - the eighth generation. Earth Planets Space, 52, 1119-1124.
Lowes, F. J. (2000) The working of the IGRF 2000 Task Force. Earth Planets Space, 52, 1171-1174.
IAGA Division V Working Group 8 (2003) The 9th Generation International Geomagnetic Reference Field. Earth Planets Space, 55(8), i-ii; Geophys. J. Int., 155, 1051-1056.
Macmillan, S. and S. McLean (2003) IAGA Division V-MOD Geomagnetic Field Modeling: Minutes Hanoi 2001. http://www.ngdc.noaa.gov/IAGA/vmod/min2001.html, 23 September, 2003.
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Nakatsuka, T. (2004) Calculation of the International Geomagnetic Reference Field (3). GSJ Open-File Report, no.402, 39p. + 1 diskette, Geol. Surv. Japan, AIST.
Maus, S. and S. Macmillan (2005) 10th Generation International Geomagnetic Reference Field. EOS, 86(16), 159.
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