Enhanced Magnetic Model 2010
Declination Comparison of WMM and EMM
The Enhanced Magnetic Model (EMM) extends to degree and order 720, resolving magnetic
anomalies down to 56 km wavelength. The higher resolution of the EMM results in significantly
improved pointing accuracy than the World Magnetic Model (WMM), which uses spherical
harmonic representation to degree and order 12, resolving the magnetic field at 3000
km wavelength. The EMM model provides the magnetic field vector at any desired location
and altitude close to and above the Earth's surface.
- Cite as: NCEI Geomagnetic Modeling Team. 2009: Enhanced Magnetic Model 2010. 3. NOAA
National Centers for Environmental Information. Accessed [date].
- NCEI Metadata ID: gov.noaa.ngdc.mgg.geophysical_models:EMM2010
gov.noaa.ngdc.mgg.geophysical_models:EMM2010
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Download Data |
- EMM2010_Sph_Windows_Linux.zip (download)
Enhanced Magnetic Model (EMM2010) and software using the spherical harmonic approach
for Windows and Linux environments. High CPU requirements (use the faster Mesh software
for large number of points), very low RAM requirement (7.5 MB). For use with years
2000 to 2015.
- EMM2010_Mesh_Windows_Linux.zip (download)
Enhanced Magnetic Model (EMM2010) with software with rapid field calculation using
3D mesh interpolation for Windows and Linux environments. Low CPU requirements, High
(1.4 GB) RAM requirement. Only works for years 2010-2015, for 2000-2010 please download
the spherical harmonic version above.
- EMM2010_Dec-15-09.zip (download)
Enhanced Magnetic Model (EMM2010) with software for point and grid calculation.
- EMM-720_V3p0.tar.gz (download)
Enhanced Magnetic Model with software for rapid field calculation using 3D mesh interpolation.
- EMM-720_V3p0_static.cof.gz (download)
Enhanced Magnetic Model. Spherical Harmonic Coefficients of the static internal field
at 2010.0.
- EMM-720_V3p0_secvar.cof.gz (download)
Enhanced Magnetic Model. Spherical Harmonic Coefficients of the estimated secular
variation 2010-2015.
- EMM-06.tar.gz (download)
Software for the Enhanced Magnetic Model (EMM-06), including main field, secular variation,
NGDC-720-V1 crustal field, magnetospheric field, and induced field. The package includes
a simple single-point program and a thread-safe multi-processor application which
can be adapted to produce large grids and time series.
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Distribution Formats |
- EMM2010_Sph_Windows_Linux.zip (Version:4)
- File Specification: Enhanced Magnetic Model (EMM2010) and software using the spherical harmonic approach
for Windows and Linux environments. High CPU requirements (use the faster Mesh software
for large number of points), very low RAM requirement (7.5 MB). For use with years
2000 to 2015.
- EMM2010_Mesh_Windows_Linux.zip (Version:3)
- File Specification: Enhanced Magnetic Model (EMM2010) with software with rapid field calculation using
3D mesh interpolation for Windows and Linux environments. Low CPU requirements, High
(1.4 GB) RAM requirement. Only works for years 2010-2015, for 2000-2010 please download
the spherical harmonic version above.
- EMM2010_Dec-15-09.zip (Version:1)
- File Specification: Enhanced Magnetic Model (EMM2010) with software for point and grid calculation.
- EMM-720_V3p0.tar.gz (Version:3)
- File Specification: Enhanced Magnetic Model with software for rapid field calculation using 3D mesh interpolation.
- EMM-720_V3p0_static.cof.gz (Version:3)
- File Specification: Enhanced Magnetic Model. Spherical Harmonic Coefficients of the static internal field
at 2010.0.
- EMM-720_V3p0_secvar.cof.gz (Version:3)
- File Specification: Enhanced Magnetic Model. Spherical Harmonic Coefficients of the estimated secular
variation 2010-2015.
- EMM-06.tar.gz (Version:3)
- File Specification: Software for the Enhanced Magnetic Model (EMM-06), including main field, secular variation,
NGDC-720-V1 crustal field, magnetospheric field, and induced field. The package includes
a simple single-point program and a thread-safe multi-processor application which
can be adapted to produce large grids and time series.
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Ordering Instructions |
Contact NCEI for other distribution options and instructions. |
Distributor |
NOAA National Centers for Environmental Information ncei.info@noaa.gov |
Dataset Point of Contact |
NOAA National Centers for Environmental Information ncei.info@noaa.gov
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Dataset Point of Contact |
NCEI Geomagnetic Modeling Team NOAA National Centers for Environmental Information geomag.models@noaa.gov
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Time Period |
2000-01-01 to 2014-12-31 |
Spatial Reference System |
urn:ogc:def:crs:EPSG::4326 |
Spatial Bounding Box Coordinates |
West:-180
East:180
South:-90
North:90
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Spatial Coverage Map |
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Publication Dates |
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Edition |
3 |
Data Presentation Form |
mapDigital
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Dataset Progress Status |
Complete - production of the data has been completed Historical archive - data has been stored in an offline storage facility |
Data Update Frequency |
As needed |
Purpose |
Magnetic anomaly maps provide insight into the subsurface structure and composition
of the Earth's crust. Over continental areas, magnetic anomalies illuminate geologic,
tectonic, and geothermal evolution of crust and lithosphere. In the world's oceans,
anomalies trending parallel to the isochrons (lines of equal age) reveal the temporal
evolution of oceanic crust. Magnetic maps are widely used in the geological sciences
and in resource exploration. |
Use Limitations |
- Produced by the NOAA National Centers for Environmental Information. Not subject to
copyright protection within the United States.
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Dataset Citation |
- Cite as: NCEI Geomagnetic Modeling Team. 2009: Enhanced Magnetic Model 2010. 3. NOAA
National Centers for Environmental Information. Accessed [date].
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Cited Authors |
- NCEI Geomagnetic Modeling Team
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Publishers |
- NOAA National Centers for Environmental Information
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Theme keywords |
Global Change Master Directory (GCMD) Science Keywords
- Earth Science > Solid Earth > Geomagnetism > Magnetic Field
- Earth Science > Solid Earth > Geomagnetism > Magnetic Intensity
- Earth Science > Solid Earth > Geomagnetism > Magnetic Declination
- Earth Science > Solid Earth > Geomagnetism > Magnetic Inclination
- Earth Science > Solid Earth > Geomagnetism > Magnetic Anomalies
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Data Center keywords |
Global Change Master Directory (GCMD) Data Center Keywords
- DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA,
U.S. Department of Commerce
- DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department
of Commerce
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Place keywords |
Global Change Master Directory (GCMD) Location Keywords
- Geographic Region > Global
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Use Constraints |
- Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability,
or completeness of furnished data. Users assume responsibility to determine the usability
of these data. The user is responsible for the results of any application of this
data for other than its intended purpose.
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Access Constraints |
- Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding
these data, nor does the fact of distribution constitute such a warranty. NOAA and
NCEI cannot assume liability for any damages caused by any errors or omissions in
these data. If appropriate, NCEI can only certify that the data it distributes are
an authentic copy of the records that were accepted for inclusion in the NCEI archives.
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Other Constraints |
Cite as: NCEI Geomagnetic Modeling Team. 2009: Enhanced Magnetic Model 2010. 3. NOAA
National Centers for Environmental Information. Accessed [date]. |
Fees |
- In most cases, electronic downloads of the data are free. However, fees may apply
for custom orders, data certifications, copies of analog materials, and data distribution
on physical media.
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Lineage information for:dataset
Processor |
- NOAA National Centers for Environmental Information
- NOAA National Centers for Environmental Information
- NOAA National Centers for Environmental Information
- NOAA National Centers for Environmental Information
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Processing Steps |
- Measurements during daytime and during periods of strong solar activity are contaminated
by external current systems, which are difficult to accurately model. Therefore, only
nighttime data during magnetically quiet periods were used in estimating the WMM coefficients.
- Some contributions to the measured magnetic field, such as the diamagnetic effect
of ionospheric plasma (Lühr et al, 2003) or motional induction by tidal ocean currents
(Kuvshinov and Olsen, 2005; Maus, 2007), can be accurately modeled and were corrected
for prior to the estimation of the WMM main field coefficients.
- To account for the contributions that have not been removed in the previous steps,
an extended set of model parameters is co-estimated with the WMM model coefficients.
These account for smaller-wavelength internal magnetic field contributions (spherical
harmonic degree larger than 12), second time derivatives (secular acceleration) and
contributions from currents external to the Earth. The set of WMM coefficients plus
the extended model parameters is called a parent model of the WMM. Two different parent
models were produced, reflecting different modeling strategies employed by NGDC for
the main field model and BGS for the secular variation model.
- Satellite, marine, and aeromagnetic measurements were compiled into an ellipsoidal
degree-720 magnetic model of the Earth's lithosphere. This model accurately represents
the crustal field down to wavelengths of approximately 56 kilometers. This results
in a higher pointing accuracy.
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Source Datasets |
- INTERMAGNET Observatory Data
- GEODAS magnetic data
- Description of Source: Trackline magnetics observations hosted on GEODAS at the National Geophysical Data
Center (NGDC).
- Spatial extent used:N:90 S:-90 E:180 W:-180
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Lineage information for:repository
Processing Steps |
- 2015-04-22T00:00:00 -NOAA created the National Centers for Environmental Information (NCEI) by merging
NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC),
and National Oceanographic Data Center (NODC), including the National Coastal Data
Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations
Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
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Last Modified: 2020-05-14
For questions about the information on this page, please email:
ncei.info@noaa.gov