Bedmap3 maps Antarctica’s buried bedrock at 500-meter resolution, giving scientists one of their clearest views yet of the continent beneath 27 million cubic kilometers of ice.
The new map shifts a key finding on ice thickness: the deepest ice is now placed in a canyon in Wilkes Land at 4,757 meters, not the long-assumed Astrolabe Basin in Adélie Land.
Researchers say the bedrock matters because much of the ice sheet sits below sea level, where relatively warm ocean water can intrude under the ice and speed melting.
That makes Bedmap3 a core input for glacier and climate models, helping refine forecasts for how Antarctica will respond to warming; a full melt would raise global sea levels by about 58 meters.
With climate models underestimating Antarctica's melt, what is the new timeline for catastrophic sea-level rise?
With Antarctica melting faster than predicted, what radical interventions could prevent a global sea-level disaster?
As hidden canyons accelerate Antarctica's thaw, are iconic species like Emperor penguins facing inevitable extinction?
Bedmap3 Reveals 27 Million km³ of Antarctic Ice: New Map Exposes Hidden Vulnerability and Global Sea-Level Threat
Overview
In March 2025, international scientists from the British Antarctic Survey released Bedmap3, a groundbreaking map that offers the most precise view yet of Antarctica’s hidden bedrock. This new map reveals that the Antarctic Ice Sheet is generally thicker than previously thought and that a larger volume of ice is grounded below sea level. Because ice grounded below sea level is more vulnerable to melting from warm ocean water, Bedmap3 enables scientists to make more accurate predictions about future ice sheet changes and better assess the risks of ice loss and global sea-level rise. These insights are already reshaping our understanding of Antarctica’s vulnerability.