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The
Enhanced Magnetic Model (EMM) is a sister product of the NGDC featuring a much higher amount of data to degree and order 790, giving a wavelength of 51 km as opposed to the 3000 km of WMM. At this resolution, it is not only able to model the
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Updated model coefficients are released at 5-year intervals, with WMM2015 (released Dec 15, 2014) supposed to last until
December 31, 2019. However, due to extraordinarily large and erratic movements of the
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of the geomagnetic main field generated in the Earth's core. Apart from the 168 spherical-harmonic "Gauss" coefficients, the model also has an equal number of spherical-harmonic
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108:(BGS). The model, associated software, and documentation are distributed by the NGDC on behalf of
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coefficients predicting the temporal evolution of the field over the upcoming five-year epoch.
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WMM model and software can be downloaded from the
National Geophysical Data Center's WMM page
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92:(FAA). It is also used widely in civilian navigation systems as the magnetic model of the
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at the core-mantle boundary ("main field"), but also take into account
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153:: another model, of similar quality, which models past years as well
265:"Earth's magnetic field is acting up and geologists don't know why"
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World
Magnetic Model method in the Android operating system
88:(WHO) navigation and attitude/heading reference, and the
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map at sea-level for the year 2010 derived from WMM2010.
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National
Centers for Environmental Information (NCEI).
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Large spatial-scale model of the Earth's magnetic field
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National
Centers for Environmental Information (NCEI)
238:"The World Magnetic Model and Associated Software"
177:Essentials of Positioning and Location Technology
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220:"Airport Runway Names Shift with Magnetic Field"
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242:National Centers for Environmental Information
199:"The US/UK World Magnetic Model for 2015-2020"
359:World Magnetic Model 2015 NOAA press release
141:caused by the minerals in the Earth's crust.
72:WMM is the standard geomagnetic model of the
46:. The data and updates are issued by the US
57:The model consists of a degree and order 12
179:, p. 110, Cambridge University Press, 2013
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151:International Geomagnetic Reference Field
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110:National Geospatial-Intelligence Agency
48:National Geospatial-Intelligence Agency
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263:Witze, Alexandra (January 9, 2019).
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78:Ministry of Defence (United Kingdom)
100:. The WMM is produced by the U.S.
74:United States Department of Defense
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313:"World Magnetic Model | NCEI"
82:North Atlantic Treaty Organization
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104:(NGDC) in collaboration with the
122:U.S. federal government shutdown
102:National Geophysical Data Center
40:National Geophysical Data Center
328:"Enhanced Magnetic Model (EMM)"
90:Federal Aviation Administration
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197:Chulliat, Arnaud; et al.
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128:Enhanced Magnetic Model (EMM)
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290:10.1038/d41586-019-00007-1
106:British Geological Survey
86:World Hydrographic Office
63:magnetic scalar potential
52:Defence Geographic Centre
44:British Geological Survey
135:Earth's magnetic field
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94:World Geodetic System
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98:magnetic declination
32:World Magnetic Model
24:Magnetic declination
281:2019Natur.565..143W
226:. 16 November 2017.
118:north magnetic pole
139:magnetic anomalies
59:spherical harmonic
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332:www.ngdc.noaa.gov
275:(7738): 143–144.
244:. 4 February 2019
67:secular variation
61:expansion of the
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246:. Retrieved
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84:(NATO), the
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76:(DoD), the
50:and the UK
248:6 February
185:1107354803
163:References
368:Category
299:30626958
145:See also
42:and the
277:Bibcode
208:. NOAA.
112:(NGA).
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269:Nature
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80:, the
202:(PDF)
295:PMID
250:2019
181:ISBN
30:The
285:doi
273:565
36:WMM
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
