EMAG2: Earth Magnetic Anomaly Grid (2-arc-minute resolution)

EMAG2 is a global Earth Magnetic Anomaly Grid compiled from satellite, ship, and airborne magnetic measurements. It is a significant update of our previous candidate grid for the World Digital Magnetic Anomaly Map. The resolution has been improved from 3 arc-minutes to 2 arc-minutes, and the altitude has been reduced from 5 km to 4 km above the geoid. Additional grid and track line data have been included, both over land and the oceans. Wherever available, the original shipborne and airborne data were used instead of precompiled oceanic magnetic grids. Interpolation between sparse track lines in the oceans was improved by directional gridding and extrapolation, based on oceanic crustal age model. The longest wavelengths (>330 km) were replaced with the latests CHAMP satellite magnetic field model MF6.

Data and Resources

Additional Info

Field Value
Last Updated June 10, 2017, 18:17
Created June 10, 2017, 18:17
access_constraints []
bbox-east-long 180
bbox-north-lat 90
bbox-south-lat -90
bbox-west-long -180
contact-email geomag.models@noaa.gov
coupled-resource []
dataset-reference-date [{"type": "publication", "value": "2009-08-07"}]
frequency-of-update asNeeded
graphic-preview-description EMAG2 looking north-west at Portugal/Spain from the Atlantic. Kursk (Russia) is seen as a strong anomaly in the background. The stripes on the left of the image are magnetic lineations due to sea-floor spreading.
graphic-preview-file http://geomag.colorado.edu/images/Looking_NW_at_Spain_s.jpg
graphic-preview-type jpg
guid gov.noaa.ngdc.mgg.geophysical_models:EMAG2
licence ["Cite as: Stefan Maus (2009): EMAG2: Earth Magnetic Anomaly Grid (2-arc-minute resolution). National Geophysical Data Center, NOAA. Model. doi:10.7289/V5MW2F2P [access date]", "Produced by the NOAA National Geophysical Data Center. Not subject to copyright protection within the United States.", "Not to be used for navigation. Although these data are of high quality and useful for planning and modeling purposes, they are not suitable for navigation. For navigation, please refer to the NOS nautical chart series.", "While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty."]
metadata-date 2015-08-31
metadata-language
progress completed
resource-type dataset
responsible-party [{"name": "DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce", "roles": ["pointOfContact"]}]
spatial {"type": "Polygon", "coordinates": [[[-180.0, -90.0], [180.0, -90.0], [180.0, 90.0], [-180.0, 90.0], [-180.0, -90.0]]]}
spatial-data-service-type
spatial-reference-system urn:ogc:def:crs:EPSG::4326
spatial_harvester true
temporal-extent-begin 1946-01-01
temporal-extent-end 2008-12-01