Antarctica is primarily freshwater.
The Freshwater Giant
The Antarctic ice sheet is overwhelmingly composed of freshwater. In fact, it holds approximately 70% of the Earth's fresh water. This massive reservoir of ice significantly impacts global sea levels. The reference material states: "The present Antarctic ice sheet accounts for 90 percent of Earth's total ice volume and 70 percent of its fresh water. It houses enough water to raise global sea level by 200 ft." This underscores the immense scale of freshwater locked within the Antarctic ice.
While the surrounding Southern Ocean is saltwater, the ice itself is formed from frozen precipitation (snow), making it freshwater. Melting this ice would significantly increase global sea levels, but wouldn't change the salinity of the ocean in a significant, localized way. The impact would be a global dilution.
- Key takeaway: While the Antarctic region includes a saltwater ocean, the Antarctic ice sheet itself is overwhelmingly freshwater.
