El desempeño del Modelo Magnético Mundial 2020 (WMM2020) se evaluó comparando sus predicciones del 1 de enero de 2024 con la de un modelo más reciente e inferido de los datos recopilados por los satélites Swarm de la Agencia Espacial Europea (ESA) hasta septiembre de 2023. Para todos los componentes del campo magnético, el error cuadrático medio global de WMM2020 aumentó en menos del 10% de su valor anterior en los últimos cuatro años y se mantuvo muy por debajo del error máximo permitido por el Departamento de Defensa de EE. UU, en sus especificaciones para el WMM. Esto sugiere que los cambios no lineales en el campo magnético de la Tierra se han mantenido pequeños durante los últimos tres años. Desde el 2020, el polo de inmersión magnético norte se ha movido a una velocidad promedio de 41 km/año, y el polo sur magnético, polo de inmersión a 9 km/año. Ninguno de los dos experimentó ningún cambio de dirección notable.
Summary
The performance of the World Magnetic Model 2020 (WMM2020) was assessed by comparing its predictions on January 1, 2024 with that of a more recent model inferred from data collected by the European Space Agency (ESA) Swarm satellites until September 2023. For all magnetic field components, the global root-mean-square error of WMM2020 increased by less than 10% of its previous value over the past four years and remained well below the maximum error allowed by the U.S. Department of Defense WMM specification. In addition, the WMM2020 secular variation was again deemed an accurate approximation of the actual secular variation observed at ground-based observatories and Swarm-based geomagnetic virtual observatories up to 2023. This suggests that nonlinear changes in the Earth’s magnetic field have remained small over the past three years.
Since 2020, the north magnetic dip pole has moved at an average speed of 41 km/yr, and the south magnetic dip pole at 9 km/yr. Neither underwent any noticeable change in direction. These movements led to minor changes in the shape and location of the WMM blackout zones, where compass accuracy is highly degraded. The South Atlantic Anomaly, where the geomagnetic field intensity is lowest, has continued to deepen (by about 25 nT at surface level) and move westward (its center moved by about 20 km at surface level) in the past year. Over the past year, three strong to severe geomagnetic storms occurred, leading to significant (e.g., declination deviations over 9 degrees) but temporary effects on WMM performance, mostly at high geomagnetic latitudes. As WMM2025 is anticipated for release in December 2024, this marks the final report on WMM2020.
Fuente: https://www.ngdc.noaa.gov
