Why in news?
Recent data shows the SAA is expanding and intensifying, with the magnetic field weakening further, raising concerns about potential impacts on technological systems and natural phenomena.

About South Atlantic Anomaly (SAA)

• The SAA is a region over the South Atlantic Ocean and parts of South America where the Earth's magnetic field is significantly weaker than normal.​
• It occurs because the Earth's inner Van Allen radiation belt comes closest to the surface here, at about 200 kilometers altitude, causing an increased flux of energetic charged particles in this area.​
• This weak magnetic field zone leads to higher exposure of satellites and spacecraft in low-Earth orbit to ionizing radiation, which can cause technical malfunctions and requires extra shielding (e.g., on the International Space Station).​
• The anomaly has been growing and intensifying, with the magnetic field weakening about 9% over the last 200 years and continuing to change its shape and location slowly.​
• The SAA is important scientifically as it provides clues about Earth's core processes and may be related to the long-term geomagnetic pole reversal where the north and south magnetic poles swap positions.​

The anomaly arises from complex geodynamic processes in Earth’s outer core, including the tilt of the magnetic axis and molten metal flow, causing a dip and distortion in the magnetic field.​

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