POMME is a main field model providing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. POMME-3.1 includes the time varying core field, crustal field, the ring current field modulated by the Dst/Est/Ist Indices, a time averaged magnetospheric field, the penetration of the horizontal part of the Interplanetary magnetic field (IMF), and the fields induced by Earth rotation in the external fields.

Six years of low-orbit CHAMP satellite magnetic measurements have provided an exceptionally high-quality data resource for lithospheric magnetic field modeling. Our fifth generation satellite-only magnetic field model MF5 extends to spherical harmonic degree 100. As a result of careful data selection, extensive corrections, filtering and line-leveling, the model has low noise levels and can be safely evaluated at the Earth’s surface. The model is particularly suited for inferring large-scale structure and composition of the lithosphere.

Marine and airborne magnetic anomaly data have been collected for more than half a century, providing global coverage of the Earth. Due to the changing main field from the Earth's core, and due to differences in quality and coverage, combining these data to a consistent global magnetic grid is challenging. The World Digital Magnetic Anomaly Map (WDMAM) project is an international effort to integrate all available near-surface and satellite magnetic anomaly data.

POMME is a main field model providing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. Seven years of highly accurate CHAMP satellite magnetic measurements offer an unprecedented opportunity to track the time variations of the field originating in the Earth's core. An interesting question is whether we can start to see changes in the secualar acceleration (2nd time derivative) of the geomagnetic field.

Satellites in low-Earth orbit (LEO) provide the most effective means of mapping the long wavelengths of the magnetic field caused by the magnetization of the Earth's crust. The first global magnetic anomaly maps were produced from POGO (1960s) and Magsat (1979) satellite measurements. A breakthrough in resolution and accuracy was achieved with the CHAMP satellite, launched in July 2000. Apart from an order of magnitude improvement in magnetometer accuracy, CHAMP was designed to remain in LEO for many years, leading to excellent spatial coverage.

rint map (paper and digital download) of EMAG2 available at BGR Geoshop

GIS GeoTIFF versions of EMAG2 included in the product table at the bottom of this page

POMME is a main field model providing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. The time variations of the field are represented by a Taylor series of the spherical harmonic (Gauss) coefficients of the magnetic potential. We provide the static coefficients for 2005.0 and the first and second time derivatives (secular variation and secular acceleration). The corresponding geomagnetic power spectrum is shown in Figure 1.

POMME is a main field model providing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. The time variations of the field are represented by a Taylor series of the spherical harmonic (Gauss) coefficients of the magnetic potential. We provide the static coefficients for 2005.0 and the first and second time derivatives (secular variation and secular acceleration).

POMME is a scientific main field model representing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. The time variations of the internal field are given by a piece-wise linear representation of the spherical harmonic (Gauss) coefficients of the magnetic potential.