The ocean is a major player in the regulation of the world’s climate system. The purpose of the report is to provide information to underpin the outcomes of COP21 and in particular to demonstrate the importance of the role of MPAs in climate change adaptation and mitigation. To do this the report brings together scientific information on how MPAs can help to solve climate change issues in coastal and ocean ecosystems. The focus is on ocean warming, sea-level rise, change in currents, and other associated phenomena. The scope of the report is intended to cover all marine ecosystems from coastal to open and deep sea.