A minimum set of key ocean variables, agreed internationally, that are critical to understanding and track ocean change, guiding policy, and can be observed feasibly and cost-effectively across platforms.
Indicators are scientifically validated metrics translating complex ocean changes (e.g., biogeochemical ones) into measurable, policy-relevant information.
A phenomenon in the ocean-indicator context is a distinct and meaningful process, state, or change in the ocean system (physical / biogeochemical / ecosystem) that is observable (or measurable) and for which indicators can be developed to monitor its status, trend or variability.