Les premiers pas de la météo du noyau Terrestre

Les$premiers$pas$de$la$météo$du$noyau$Terrestre$
Pourquoi$l’intensité$du$champ$magnétique$Terrestre$a-t-elle$décru$de$10%$
entre$1840$et$nos$jours?$L’anomalie$sud-Atlantique$de$ce$champ,$au$dessus$
de$ laquelle$ le$ matériel$ embarqué$ dans$ les$ satellites$ subit$ le$ plus$ grand$
nombre$d’avaries,$va-t-elle$encore$se$creuser$dans$le$siècle$à$venir?$Quand$
se$produira$la$prochaine$inversion$des$pôles$magnétiques?$La$modélisation$
opérationnelle$de$la$géodynamo$vise$à$répondre$à$ces$questions,$et$livre$ces$
jours-ci$de$ premiers$éléments$au$ travers$de$deux$ articles$publiés$ dans$les$
revues$Nature'communications$et$Geophysical'Journal'International.$$
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Un tourbillon géant à la surface du noyau
1850 1900 1950 2000 2050 2100
époque
28
29
30
31
32
intensité
du dipôle (µT)
observation
prédiction pour le futur

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