En t\u00e9rminos de aplicaciones militares, el WMM resulta indispensable para la navegaci\u00f3n submarina y a\u00e9rea, as\u00ed como para el despliegue de paraca\u00eddas, el seguimiento de antenas, la determinaci\u00f3n de la deriva del iceberg y muchas otras actividades.\u00a0En el sector privado, el modelo se puede encontrar en pr\u00e1cticamente todos los tel\u00e9fonos inteligentes.\u00a0La industria de las aerol\u00edneas comerciales tambi\u00e9n lo utiliza para que reflejen con precisi\u00f3n su rumbo magn\u00e9tico y permitan una mayor claridad durante los procedimientos de aterrizaje.<\/p>\n
Last month saw the publication of the\u00a02022 State of the Geomagnetic Field Report<\/a>. The report details the current state of Earth\u2019s main magnetic field, and provides a performance analysis of the most recent version of the\u00a0World Magnetic Model (WMM)<\/a>\u00a0released in late 2019, known as WMM2020. Comparisons between the predictions of WMM2020 and recent data collected from the European Space Agency (ESA)\u2019s Swarm satellites indicate that the former can still be considered an accurate model.<\/p>\n As the WMM is predictive in nature, it becomes less accurate over time and must be updated with the newest projections derived from more recently collected data.<\/p><\/blockquote>\n Most of our planet\u2019s magnetism originates from the shifting of electrically charged molten metals in its outer core, the behavior of which is unpredictable. An example of the secular changes that these metals can cause is the slow drifting of Earth\u2019s magnetic north pole towards Siberia, a process that has been occurring continuously for the past few decades.\u00a0As the WMM is predictive in nature, it becomes less accurate over time and must be updated with the newest projections derived from more recently collected data.<\/span>\u00a0Updates are scheduled to occur every five years.<\/p>\n In the private sector, the model can be found in virtually every smartphone.<\/p><\/blockquote>\n The WMM is a joint project between the National Centers for Environmental Information (NCEI) and the British Geological Survey (BGS). It is utilized by these agencies\u2019 respective governments for their navigation, attitude, and heading software. In terms of military applications, the WMM proves indispensable for undersea and aircraft navigation as well as parachute deployment, antenna tracking, iceberg drift determination and many other activities.\u00a0In the private sector, the model can be found in virtually every smartphone.<\/span>\u00a0The commercial airline industry also uses it to rename airport runways so that they accurately reflect their magnetic heading to allow for greater clarity during landing procedures.<\/span><\/p>\n The South Atlantic Anomaly Grows<\/strong><\/p>\n Also described in the State of the Magnetic Field Report is the deepening of the South Atlantic Anomaly (SAA), an area spanning the South Atlantic Ocean and South America where the Earth\u2019s magnetism is weakest. This area is known to cause radiation damage to satellites and problems with radio propagation, issues that are exacerbated by the SAA\u2019s growth in size by five percent over the past three years. NCEI continues to monitor the situation closely.<\/p>\n A well-known limitation of the WMM is the tendency for its accuracy to drop during magnetic storms, of which there were three that were strong to severe in the past year. These space weather events can cause disparities between actual magnetic declination and the estimated declination provided by the WMM that are temporarily greater than the model uncertainty, especially at high latitudes. This year\u2019s report includes descriptions of the three storms in order to alert users to this limitation to the WMM. Fortunately, the model takes space weather into account in its error estimates.<\/p>\n Regardless of these minor concerns, all data gathered for the annual report indicates that the WMM2020 is still operating well below the margin of error stipulated by the U.S. Department of Defense. The model can thus continue to be relied on by all technology that implements it.<\/p>\n