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EMAG2, background image © GFZ Potsdan 1999

What's New?

new High Def Geomagnetic Model (HDGM2016)!
new CIRES geomagnetism page
new Enhanced Magnetic Model 2015!

Models are joint research with:

The Cooperative Institute for Research in Environmental Sciences (CIRES).


The study of geomagnetism is one of the oldest of the geophysical sciences. The geomagnetic fields have been observed and used from ancient times. Modern uses of geomagnetic data include navigation and mineral exploration. The National Centers for Environmental Information develops and distributes models of the geomagnetic field and maintains archives of geomagnetic data to further the understanding of Earth magnetism and the Sun-Earth environment.

Online Calculators
Declination Grid Calculation Magnetic Field US Historic Declination
NOAA has updated the magnetic calculator(s). The older style calculators will continue to be available for some time through the CIRES Geomagnetism research site. Follow the following off-site link for access to the backup calculators.

Geomagnetic Models &Software
Enhanced Magnetic Model (EMM) Intl Geomagnetic Reference Field (IGRF)
World Magnetic Model (WMM) Maps and Images (ftp)
new High Definition Geomagnetic Model (HDGM) Historic Declination Mapviewer 

Geomagnetic Data
Airborne Observatory
Indices Paleomagnetic
Marine Magnetic

Geomagnetism Poster Geomagnetism Tri-Fold
WMM Handout Geomagnetism Impact Handout
Geomagnetic Services Handout

Trackline (marine and airborne) data and derived geomagnetic models and software are managed by NCEI and collocated World Data Center for Geophysics.

map and north arrow
Declination Calculator

World Magnetic Model (WMM) declination
World Magnetic Model

Enhanced Magnetic Model (EMM)
Enhanced Magnetic Model