Understanding the Power of Auroras and Geomagnetic Storms: Safeguarding Critical Infrastructure
Context: Researchers in Frontiers in Astronomy and Space Sciences have shown that the angle at which interplanetary shocks hit Earth’s magnetic field determines the strength of geomagnetically induced currents.
This discovery opens doors to predicting and protecting against potentially damaging shocks to essential infrastructure.
Auroras long revered in myth, now exert their influence on modern technology that relies on electricity. These celestial displays are generated by forces that also generate currents capable of damaging electrically conductive infrastructure.
Auroras and GIC share common space weather drivers.
Critical Infrastructure
- It refers to the systems, facilities and assets that are vital for the functioning of society and the economy. Their disruption would impact public safety, security and health or economic stability.
- It includes both physical and virtual components that are interconnected and interdependent.
The Science Behind Auroras and Infrastructure Damage
- Auroras and Geomagnetically Induced Currents (GICs): Auroras result from two processes:
- Particles ejected from the sun interact with Earth’s magnetic field, causing geomagnetic storms.
- Interplanetary shocks compress Earth’s magnetic field, generating geomagnetically induced currents (GICs).
- Infrastructure Vulnerability: GICs can harm infrastructure that conducts electricity, such as power grids, pipelines, and communication networks.
- Impact Angle Matters: Discovered the angle at which interplanetary shocks hit Earth is crucial. Head-on impacts induce stronger GICs because they compress the magnetic field more effectively.
- Forecasting and Protection: Understanding shock impact angles allows us to forecast dangerous events and shield critical infrastructure.
Historical Examples and Future Considerations
- 1989 Geomagnetic Storm: The Hydro-Quebec power system in Canada was shut down for nearly nine hours due to a severe geomagnetic storm. Millions of people were left without electricity.
- May 2024 Storm: The most severe storm in the past two decades expanded the auroral region (Florida in the U.S. to Ladakh in northern India) significantly, emphasising the need for vigilance.
- While extreme events grab headlines, weaker but more frequent interplanetary shocks can also pose threats over time.
About Auroras
- An aurora is a natural light display that shimmers in the sky.
- Blue, red, yellow, green, and orange lights shift gently, changing shape like softly blowing curtains.
- They are only visible at night, and usually only appear in lower polar regions.
- They are known as Aurora Borealis, or Northern Lights at the Arctic Circle and Aurora Australis, or Southern Lights at the Antarctic Circle.
- Most active auroras happen during periods of strong solar wind, which is associated with sunspots and solar flares.
- The colours of auroras depend on the altitude and the type of atoms involved:
- Green-yellow: oxygen atoms at lower altitudes.
- Red: oxygen atoms at high altitudes.
- Blue/purple: hydrogen and helium atoms (rarely seen).
- Reddish/bluish: nitrogen atoms.
- Magnetic storms and active auroras can sometimes interfere with communications. They can disrupt radio and radar signals. Intense magnetic storms can even disable communication satellites.