Projections
As climate dynamics continue to change, so will sea levels, driven by the expansion of warming ocean waters and the melting of glaciers and polar ice sheets. The ocean plays a crucial role in regulating global temperatures, absorbing more than 90% of the excess heat caused by greenhouse gas emissions. However, due to the ocean’s immense thermal inertia, this warming - and the resulting sea level rise - will continue for centuries, even if emissions are halted. The delayed response of ice sheets and ocean expansion means that sea levels are already committed to rising further. Unlike historical sea level changes, which reflect past conditions based on tide gauge and altimetry data, projections rely on climate models that simulate various scenarios of greenhouse gas emissions, global warming, and ice sheet dynamics. Regional variations add complexities of sea level change, and local factors such as vertical land movement, ocean currents, and regional weather patterns influence the rate and magnitude of change.
This page explores the anticipated future changes in sea levels as well and the contributing processes. Data can be explored by Exclusive Economic Zone (EEZ). Where appropriate, statistics for selected areas of focus can be compared to global means. Projected sea level data is from the 2021 IPCC 6th Assessment Report. All projections are relative to 2005 (1995-2015).
CCKP is grateful for the support and expertise of NASA's Sea Level Change Team (N-SLCT). All data presented has been provided by N-SLCT. For additional details about the science behind sea level change, users are encouraged to visit: https://earth.gov/sealevel
Section I – Sea Level Projections
Projected timing of the exceedance of different thresholds (increments of 0.1 m) under different SSPs is identified below as 'milestones'. The thick bars present 17th-83rd percentiles. Thin bars show 5th–95th percentiles only for SSP1-2.6 Low Confidence, SSP2-4.5 Low Confidence, and SSP5-8.5 Low Confidence scenarios. Users can select different 'milestones' by using the slider under the chart.
Section II – Contributors to Sea Level Change
Different contributing processes such as ongoing ice melt, thermal expansion, vertical land motion, and changes in terrestrial water storage are essential for understanding future sea level changes. As climate change intensifies, these processes are expected to accelerate, driving more significant regional and global sea level rise. Continued warming will have far-reaching implications for coastal areas and ecosystems, with consequences depending on local conditions and driven by location specific responses from contributing processes. Contributions are shown relative to 2005 (1993-2015).
Section III – High Tide Flooding
Projected High Tide Flooding (HTF) reflects the number of projected days that exceed one of more of the HTF thresholds above the average high tide, from 1983-2001. Rising sea levels are expected to increase the frequency of HTF events, however data presented below only tracks days when sea levels exceed designated thresholds and is not a direct indication of flood events. Projected thresholds are compared against the historical 30-year average for most recent data of Minor, Moderate, and Major HTF thresholds for selected locations.
HTF Thresholds:
Minor High Tide Flooding: 40cm (400mm)
Moderate High Tide Flooding: 60cm (600mm)
Major High Tide Flooding: 80cm (800mm)