I wonder what "mangnetic" is? Maybe-A-No-Go-netic?
Anyway, yes the magnetic field strength is decreasing, quite natural, considering that it has never been registrated being stronger than nowadays. It can only go down after that. But it's not a clear sign of a magnetic flip. It's even more likely that a (Palaeo) Magnetic Excurion (PME) could follow. They seem to happen about every 100,000 years on a global level. The field strength reduces very strongly and the bipolarity (N and S) changes apparantly to multiple poles. A PME seem to last some 5000-10,000 years
This (fig 1) seems to be the current consensus about the palaeo magnetic field strenght in the current "Brunhes chron" as this period with the "normal" magnetic polarity is called. There are many more reports of (local?) Palaeo-Magnetic-Excursions like this perhaps 10,000 years ago and whether or not the Mono Lake excursion (26,000 years ago) is identical to the Lachamps excursion (40,000 years ago).
Anyway, the alleged Gothenburg Paleo Magnetic Flip (12,000 years ago) has been debunked. This is the last reference that I could google up with.
Quid est ergo tempus
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