The ocean’s health is in decline. Unsustainable activities on land and in the ocean are accelerating the degradation of marine ecosystems through multiple impacts. To reduce the impacts, including climate change, they must first be measured. And then marine and costal ecosystems can be monitored, protected and healed.

Multiple human stressors in the form of unsustainable activities are part of a complex interaction with climate change. We do not know everything about ecosystems and their reactions to multiple stressors yet. But such knowledge is urgently required for creating tools for marine ecosystem management frameworks tasked with building resilience, monitoring thresholds and avoiding ecological tipping points. They will ensure that the ocean ecosystem functions sustainably, and its services continue to be provided for the benefit of society and the planet.