A new analysis by NASA indicates that climate change played a significant role in the unexpected rise in sea levels in 2024. Satellite records show that global sea levels increased by 0.23 inches during the year, surpassing the predicted 0.17 inches. Researchers attribute most of the difference to thermal expansion, where ocean waters expand as they warm, and meltwater from ice sheets. This unusual combination of factors led to the accelerated sea level rise seen in 2024.
Josh Willis, a sea level researcher at NASA’s Jet Propulsion Laboratory, noted that the ocean’s rise in 2024 exceeded expectations and emphasized the increasing rate of sea level rise. The analysis revealed that the majority of recent sea level rise has been due to the melting of ice sheets and glaciers, with a smaller portion resulting from thermal expansion. However, in 2024, the proportions shifted, with expanding ocean waters accounting for two-thirds of the rise.
Nadya Vinogradova Shiffer, from NASA’s Integrated Earth System Observatory, highlighted that 2024 marked the warmest year on record, coinciding with the highest ocean levels in three decades. The annual rate of sea level rise has more than doubled since satellite records began in 1993, with sea levels rising by at least 4 inches since then. Human-induced climate change is identified as the primary driver of rising sea levels, as heat from the ocean’s surface penetrates deeper layers and El Niño events cause vertical heat movement throughout the ocean. Overall, the analysis underscores the urgent need to address climate change to mitigate further sea level rise.
