Global sea levels rose faster than expected in 2024 due to ocean warming, with thermal expansion being the main contributor. The rate of rise was higher than anticipated, increasing by 0.23 inches (0.59 cm) per year compared to the expected rate of 0.17 inches (0.43 cm). This is a significant increase from previous years, when about two-thirds of sea level rise came from melting ice sheets and glaciers.
The unusual warmth in 2024 was partly due to El Niño events that shifted heat within the ocean. Warmer water expands, causing it to rise, and this process has been accelerating over time. The satellite record shows a more than doubling of annual sea level rise since 1993, with global sea levels increasing by 4 inches (10 cm).
NASA’s analysis suggests that the ocean continues to rise, with the rate of increase getting faster. This is because heat from the surface moves slowly into deeper layers in most places, but extreme wind and currents can mix these layers, allowing heat to spread more quickly.
A new satellite, Sentinel-6 Michael Freilich, has been tracking sea level changes since 2020. Its twin will continue to monitor ocean height until its fourth decade, providing a valuable dataset for researchers. Understanding sea level rise is crucial for predicting the impact of climate change on coastal regions and ecosystems.
Source: https://www.nasa.gov/missions/jason-cs-sentinel-6/sentinel-6-michael-freilich/nasa-analysis-shows-unexpected-amount-of-sea-level-rise-in-2024