Northern lights have a dark side Auroras, while awe-inspiring, reveal critical information about disruptions to Earth’s magnetic field, especially relevant in our technology-driven era.
The forces behind auroras also generate currents that can damage electrical infrastructure, such as pipelines and power grids.
A recent study highlights that the impact angle of interplanetary shocks plays a crucial role in the strength of these currents, providing a way to predict and mitigate potential damage.
Both auroras and Geo-magnetically Induced Currents (GICs) are driven by space weather events.
Auroras serve as visual indicators that electric currents in space can produce GICs on the ground.
During severe geomagnetic storms, the auroral region can expand significantly.
Typically, its southern boundary is around 70 degrees latitude, but during extreme events like the May 2024 storm, it can extend down to 40 degrees or further, marking the most intense storm in two decades.
Auroras occur through two primary processes:
Particles from the sun striking Earth’s magnetic field or interplanetary shocks compressing the magnetic field.
These shocks can also generate GICs that threaten electrical infrastructure. The impact of interplanetary shocks on Earth’s magnetosphere significantly disturbs the geo-magnetic field and electric currents in the magnetosphere-ionosphere system.
At high latitudes, auroral electro jet currents are most affected by these shocks, generating ground-based GICs that interact with and damage artificial conductors, including power transmission lines, oil and gas pipelines, railways, and submarine cables.
Stronger shocks result in stronger currents and auroras, while frequent, less powerful shocks can also cause cumulative damage over time.
Understanding the relationship between interplanetary shocks and their impact on Earth’s magnetic field is crucial for predicting and protecting against potential damage to our electrical infrastructure.