Which lake contains about 20% of the world’s unfrozen surface freshwater?

Lake Baikal contains about 20% of the world’s unfrozen surface freshwater.

Although several lakes have larger surface areas, Baikal’s extreme depth gives it an enormous volume. It holds approximately 23,615 cubic kilometres of water, more than all the North American Great Lakes combined. This makes it the largest freshwater lake in the world by volume.

The lake lies in a deep rift valley in Siberia and receives water from hundreds of rivers and streams. Its only major outlet is the Angara River, which eventually joins the Yenisei system. The lake’s water is comparatively clear because of its low nutrient levels and distinctive ecosystem.

A common mistake is to identify Lake Superior as the world’s largest freshwater lake in every category. Superior has the greatest surface area among freshwater lakes, while Baikal leads by volume and depth.