What phenomenon is a geomagnetic disturbance (GMD) most likely to cause?

A geomagnetic disturbance (GMD) is primarily a result of solar activity, such as solar flares or coronal mass ejections, which can induce electric currents in the Earth's magnetosphere. One of the key impacts of these disturbances is the generation of geomagnetically induced currents (GICs) that can flow through electrical systems, particularly affecting transformer operations.

Transformers can experience overheating when subjected to these GICs, as the additional current can cause excessive heating, leading to potential damage. Over time, this overheating can deteriorate the insulating materials within transformers and ultimately lead to failure or reduced lifespan of the equipment. Therefore, the most significant risk associated with geomagnetic disturbances, particularly in the context of power systems, is the overheating of transformers due to the induced currents.

Understanding this phenomenon is crucial for mitigating risks associated with geomagnetic disturbances, ensuring that power systems remain reliable and resilient against solar weather events.