Reacción a "Geomagnetic anomalies in the Southern Hemisphere that pose a threat to satellites are a recurring phenomenon, according to research"

The study is of very high quality and represents a substantial advance in our understanding of the Earth’s magnetic field in the Southern Hemisphere, where robust data has historically been scarce. The authors provide 41 new absolute geomagnetic intensity measurements obtained using rigorous experimental protocols, which significantly strengthen the existing database for South America. Combining these new data with updated global models allows for the reconstruction of the evolution of geomagnetic anomalies over the past 2,000 years and demonstrates that the current South Atlantic Anomaly is neither an exceptional nor a recent phenomenon, but rather the most recent manifestation of a recurring process operating on timescales ranging from centuries to millennia. Among the limitations, which are inevitable in this type of study, it is noteworthy that the data remain spatially uneven and that some inferences regarding the migration of ancient anomalies depend on models that, although well-founded, are still constrained by the scarcity of records in other areas of the Southern Hemisphere.

The main implication of this work is that it confirms the existence of a persistent asymmetry between the northern and southern hemispheres in magnetic field strength, linked to deep dynamic processes in the Earth’s core, possibly modulated by the structure of the mantle. Understanding the southern hemisphere anomalies is key because they have direct consequences for our planet: the South Atlantic Anomaly weakens protection against cosmic radiation, affects the operation and lifespan of satellites, and even impacts technological systems. Overall, the study does not imply that we are facing an imminent magnetic field reversal, but it does clearly improve the scientific basis needed to understand the future evolution of Earth’s magnetic shield and assess its potential technological and environmental impacts.