Space Laser Analysis Confirms 90mm Global Sea Level Surge Driven by Rapidly Melting Land Ice

PolyU researchers use space lasers to track 30 years of sea level rise, finding that melting land ice is now the primary driver of global ocean mass increases.

By: AXL Media

Published: Feb 24, 2026, 8:15 AM EST

Source: The information in this article was sourced from The Hong Kong Polytechnic University

Three Decades of Precise Orbital Monitoring

New geodetic data suggests that the global mean sea level has undergone a significant transformation over the last 30 years, rising at an average rate of 3.3 mm per year. Researchers at The Hong Kong Polytechnic University utilized satellite laser ranging (SLR) to create the first direct, high-precision record of ocean mass changes spanning from 1993 to 2022. According to the study published in the Proceedings of the National Academy of Sciences, this period saw a total cumulative rise of roughly 90 millimeters, marking a clear and accelerating trend in planetary warming.

Shifting Drivers of Oceanic Volume

The mechanics of rising seas are traditionally split between the thermal expansion of warming water and the addition of physical mass from melting ice. While the oceans absorb nearly 90% of the Earth's excess trapped heat, this research highlights a critical shift in the underlying cause of sea level increases. According to the research team led by Professor Jianli Chen, approximately 60% of the total observed rise is now attributable to the growing mass of the oceans rather than simple expansion. Since 2005, this influx of new water has become the dominant force reshaping global coastlines.

Polar Deglaciation Fuels Mass Gain

The primary source of the newly measured ocean mass is the rapid disintegration of terrestrial ice reservoirs. According to the analysis, melting from mountain glaciers and polar ice sheets accounts for more than 80% of the total increase in global ocean mass over the three-decade study period. The researchers identified the Greenland ice sheet as a particularly significant contributor to this volume. This acceleration in land ice loss reflects the intensifying impact of atmospheric warming on previously stable glacial structures.