Natural occurrences of stray current in the earth that are transferred to the protected pipeline are referred to as what?

Natural occurrences of stray current in the earth that are transferred to the protected pipeline are referred to as potential gradients. This concept involves the movement of electrical energy through different conductive materials, such as soil, and across distances due to variations in electrical potential. These gradients can lead to stray currents that affect the integrity of the pipeline by facilitating corrosion processes.

Potential gradients are crucial in understanding how external electrical influences can impact the protection systems in place for pipelines. Stray currents can introduce unwanted electrochemical reactions that could compromise the pipeline's coatings and lead to corrosion, making it essential for those involved in corrosion control to recognize and manage these gradients effectively.

The other options—burial pressures, groundwater changes, and climate variations—do not specifically address the electrical characteristics or phenomena associated with stray currents affecting pipelines. Instead, they pertain to different environmental factors, such as physical forces, changes in moisture content or soil saturation, and overall weather patterns, none of which directly relate to the concept of electrical potential affecting pipeline integrity.