How fast is sea level actually rising and what are the latest projections?
Global sea level is rising faster than at any time in 3,000 years, and the latest data suggests worst-case scenarios are becoming more likely.
The answer
Global mean sea level has risen approximately 21 to 24 centimeters since 1880, with the rate accelerating from 1.4 millimeters per year throughout the 20th century to 3.6 millimeters per year from 2006 to 2015, and 4.5 millimeters per year from 2013 to 2024. The IPCC Sixth Assessment Report projects a rise of 0.28 to 1.01 meters by 2100 depending on emission scenarios, with some studies suggesting up to 2 meters if Antarctic ice sheet collapse accelerates. Thermal expansion of warming water contributes about 42% of current rise, while melting glaciers and ice sheets contribute the remainder. At least 900 million people in low-lying coastal zones face direct flooding risks. Entire island nations like Tuvalu and the Marshall Islands could become uninhabitable by 2100.
Source: NOAA
- sea level rise
- climate change
- coastal flooding
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