Greenhouse gases already in the atmosphere are likely to have persistent impacts in a range of areas, including on seas and coasts. A new report from a working group of the European Science Foundation's Marine Board has documented existing knowledge about climate change and its potential impacts on European seas and coasts. The report also makes several recommendations for future monitoring. These include a call for the research community to better predict and identify the nature and rate of the consequences of climate change on the marine environment, including marine organisms, as well as potential feedback mechanisms. The report also identifies future monitoring, modeling, and research needs.