Climate report key findings

• Sea levels are rising at unprecedented rates, accelerating in recent decades as ice has been melting increasingly fast from Greenland and Antarctica.

• They are set to rise at an increasing rate and will continue to do so beyond the year 2100 whatever level of emissions cuts are achieved.

• Sea levels are set to rise by 30-60cm by 2100 with strong action to cut emissions and by around 60-110cm with high levels of pollution. Several metres of sea-level rise is predicted for 2300 in a high-emissions world.

• Coastal communities are facing multiple threats linked to climate change, including more intense cyclones, extreme sea levels and flooding and marine heatwaves.

• The risk of erosion and flooding will increase significantly under all scenarios for future emissions, with annual coastal flood damages projected to increase 100 to 1,000 times by 2100.

• This century the ocean is set to shift to “unprecedented” conditions, with higher temperatures and more acidic waters as carbon dioxide dissolves into the seas, while extreme El Nino and La Nina events will become more frequent.

• Marine heatwaves have very likely doubled in frequency since 1982 and are increasing in intensity.

• Wildfires are set to increase across the tundra and cold northern forests.

• Marine wildlife and fish stocks are set to decline, while marine heatwaves and more acidic oceans will harm corals.

• Nearly half of the world’s coastal wetlands, which protect from erosion and flooding and are important carbon stores, have been lost over the last 100 years, as a result of human activity, rising sea levels and warming.

• Fragile habitats such as seagrass meadows and kelp forests are at high risk if global warming exceeds 2C above pre-industrial temperatures, while warm water corals are already at high risk and face “a very high risk” even if global warming is limited to 1.5C.