Working Group V-MOD: Geomagnetic Field Modelling

    IUGG > IAGA > Division V > Working Group V-MOD > IGRF Model

International Geomagnetic Reference Field

IGRF-12 is released. Download the latest IGRF model here : IGRF-12 coefficients (text file, excel spreadsheet)

Fortran program with IGRF-12 coefficients integrated into the source code.

Updated C software for evaluating IGRF-12 will be available before the end of January 2015.

The International Association of Geomagnetism and Aeronomy (IAGA) has released the 12 th Generation International Geomagnetic Reference Field — the latest version of a standard mathematical description of the Earth's main magnetic field that is used widely in studies of the Earth's deep interior, its crust and its ionosphere and magnetosphere. The coefficients for this degree and order 13 main field model were finalized by a task force of IAGA in December 2014. The IGRF is the product of a collaborative effort between magnetic field modellers and the institutes involved in collecting and disseminating magnetic field data from satellites and from observatories and surveys around the world.

The IGRF is a series of mathematical models of the Earth's main field and its annual rate of change (secular variation). In source-free regions at the Earth's surface and above, the main field, with sources internal to the Earth, is the negative gradient of a scalar potential V which can be represented by a truncated series expansion:

expansion equation

The 12 th Generation IGRF coefficients were computed from candidate sets of coefficients produced by the participating members of IAGA Working Group V-MOD. Their institutes and the many organisations involved in operating magnetic survey satellites, observatories, magnetic survey programmes and World Data Centers are to be thanked for their continuing support of the IGRF project.

Before using the IGRF please look at the "Health Warning".

Older versions of the IGRF model may be downloaded here.

For page content questions please contact: Erwan Thebault
Webpage Maintained by: Manoj Nair
Hosted by: WDC for Solid Earth and Geophysics

URL: http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html
Revised: 18 December, 2014


IUGG  > IAGA  > Division V  > Working Group V-MOD  > IGRF Model