Abstract: The key conclusions on the effects of climate change and the adaptability evaluation from the chapter 30 (The Ocean) in the Fifth Assessment Report by Working Group II of the Intergovernmental Panel on Climate Change (IPCC WGII AR5) were briefly presented in this article. The world’s non-polar ocean as a whole region was considered for the first time in this report, and it was separated into seven major sub-regions based on marine ecosystem structure and functioning as well as key oceanographic features. Assessment results indicated that, the global average sea surface temperatures have increased since the beginning of the 20th century, and uptake of CO₂ has decreased ocean pH in all ocean sub-regions, particularly at high latitudes, fundamentally changing the ocean physical and chemical properties, marine ecological systems in the past 60 years and posing a number of key risks to ocean and coastal issues from climate change, such as, distributional shift in marine species, changes to fisheries capture potential with region variations, reduced biodiversity and fisheries abundance and coastal protection by coral reef, etc. Meanwhile, the related adaptive issues and prospects were put forward. In addition, the deficiencies and difficulties in the assessment report were also discussed, as well as outlined, the related research work needed to be further explored in China.

Key words: ocean region, impact, climate change, WGII, AR5