What’s driving sea-level rise?

July 30, 2025

Sea levels are constantly changing, even without climate change. Natural variations like tides, atmospheric pressure, seasonal shifts and ocean patterns such as the El Niño–Southern Oscillation all play a role. In some places, land itself is rising or sinking, further influencing local sea levels.

But climate change is now amplifying many of these natural processes, leading to an overall acceleration in sea-level rise. As global temperatures increase, glaciers and ice sheets melt and ocean water expands, pushing sea levels higher. These changes are already affecting coastlines, communities, ecosystems and infrastructure.

This explainer unpacks the complex drivers behind sea-level rise and how human-driven climate change is altering the system. Understanding these dynamics is critical for planning and preparing for the impacts already underway and those still to come.