Coastal floods 12 times more likely due to human-driven climate change

Key facts

• Coastal floods that historically had a 1% chance of occurring annually are now 12 times more likely.
• Human-driven climate change is the primary driver of sea level rise since the 1960s.
• Greenhouse gas emissions from burning fossil fuels are the most significant factor in sea level rise.
• A separate study indicates climate change is responsible for 58% of extreme ocean height flood days between 2000-2018.
• Current coastal protection infrastructure may not be adequate for future flood risks.

New research published in Nature Climate Change reveals that coastal floods, once rare events with a 1% annual chance, are now approximately 12 times more likely on average. This increased frequency is largely attributed to human-driven climate change, which has been the primary cause of rising sea levels since the 1960s. The study, which analyzed tide gauge records and climate models, suggests that these extreme sea level events have become about four times more likely due to human influence.

A separate study in Science Advances supports these findings, indicating that climate change is responsible for about 58% of extreme ocean height flood days between 2000 and 2018. This research also found that climate change has nearly tripled the number of days with extreme flood levels since the 1970s. Experts emphasize that greenhouse gas emissions from burning fossil fuels are the dominant factor driving these changes.

Scientists warn that the findings are critical for coastal planning and infrastructure development as the planet continues to warm. The combination of high tides, storm surges, and rising sea levels poses a growing threat to hundreds of millions of people in low-lying coastal areas globally, causing billions in damages and potential loss of life. Experts suggest that current coastal protection measures, such as those for New Orleans, may become insufficient within the next few decades.