GRIMM-2(x)

GFZ Reference Internal Magnetic Model

The GFZ Reference Internal Magnetic Model (GRIMM­2) has been derived from nearly eight years of CHAMP satellite data and seven years of observatory hourly means. At high latitudes, full vector satellite data are used at all local times. By doing so, a separation is possible between, on one hand, the fields generated by the ionosphere and field aligned currents, and, on the other hand, the fields generated in the Earth's core and lithosphere. This selection technique leads to a data set where gaps are avoided during the polar summers allowing the modelling of the core field with an unprecedented time resolution. Order six B­splines are used to model the core field and the mapping of its acceleration is possible from 2001.5 to 2008.5 revealing a rapid and complex evolution over this time period at the Earth's surface. The energy in secular acceleration presents a smooth behaviour in time and is shown to increase continuously from 2003.5 to reach a maximum around 2006.0.. The static core field and its secular variation are all in good agreement with previously published magnetic field models.

Map illustration of GRIMM-2: Secular acceleration at the Earth’s surface from 2002.0 to 2008.0.
GRIMM-2: Secular acceleration at the Earth’s surface from 2002.0 to 2008.0.

Download

FileFormatSizeDateContent
GRIMM-2.zip ZIP81kB

July 2009

Fortran95 code for forward modelling for GRIMM-2 and a single epoch model from GRIMM-2, coefficent file.
GRIMM2x.zip ZIP89kBOct. 2009Fortran95 code for forward modelling for GRIMM-2x and a single epoch model from GRIMM-2x, coefficent file.

Contact

Profile photo of  Dr. Monika Korte

Dr. Monika Korte
Geomagnetism

Behlertstraße 3a
Building K 3, room 116
14467 Potsdam
tel. +49 331 288-1268