A lake is a water body surrounded by land with or without inlets and outlet water bodies like rivers. Lakes are larger and deeper than ponds but no official standards exist to determine the threshold level above which a water body qualifies to be a lake.
Lakes have often been ranked based on their surface area, maximum depth, average depth, age, and volume. The largest lakes by volume in each continent of the world have been mentioned below.
7. Africa: Lake Tanganyika
Africa’s largest and the world’s second-largest lake by volume, Lake Tanganyika is divided among the four African nations of Tanzania, DRC, Burundi, and Zambia. The former two countries possess the majority of the lake’s area. Lake Tanganyika holds 18,900 cubic km of water. It is the world’s second deepest lake (maximum depth is 1,470 m) and second oldest (freshwater) lake. Lake Tanganyika has alkaline waters with a pH of around 9 near the surface. The pH decreases with depth and is around 8.3 to 8.5 in the deepest parts. The temperature of the lake’s waters ranges from around 28 degrees celsius at the surface to around 23 degrees celsius near the bottom. Due to its great depth, Lake Tanganyika is stratified with little seasonal mixing of its waters. The deepest parts of the lake are completely devoid of oxygen and hence aerobic life forms do not exist at such depths.
6. Antarctica: Lake Vostok
Lake Vostok is the largest lake in Antarctica by volume. It is a subglacial lake that is located at the beneath the Vostok Station of Russia in the southern Pole of Cold. The lake remains hidden under the East Antarctic Ice Sheet. Lake Vostok holds a water volume of 5,400 cubic km. It has a surface area of 12,500 square km and a maximum depth of 510 m. The surface of the lake is around 500 m below sea level. Russian geographer Andrey Kapitsa first suggested the existence of the lake on the basis of the seismic recording made during the Antarctic expeditions conducted by the Soviet Union. It is estimated that since the lake has remained in its current undisturbed state for millions of years, there is a possibility of the existence of unique life forms in the water body found nowhere else in the world.
5. Australia: Lake Eyre
Lake Eyre, a shallow endorheic lake, is Oceania’s largest lake by volume. When full, it can hold around 30 cubic km of water and has the same salinity levels as the sea. This lake hosts Australia’s lowest natural point that is about 15 m below sea level. Lake Eyre is located around 700 km north of Australia in Northern South Australia. The water level in this lake fluctuates considerably in the different seasons of the year.
4. Europe: Lake Ladoga
Lake Ladoga is the largest European lake by volume. It is a freshwater lake located in northwestern Russia close to Saint Petersburg. Ir has a water volume of 908 cubic km. The Karelian Isthmus separates Lake Ladoga from the Baltic Sea. The Neva River drains it into the Gulf of Finland. Lake Ladoga is a navigable lake. It has around 660 islands. The lake is rich in aquatic life and even has an endemic seal species called the Ladoga seal.
3. South America: Lake Titicaca
With a water volume of 893 cubic km, Lake Titicaca is South America’s largest lake by volume. It is a massive and deep lake straddling the border between Peru and Bolivia in the Andes. Although Lake Titicaca is located at an altitude of 3,812 m it is still navigable earning it the title of the world’s "highest navigable lake”. Many rivers and streams flow into Lake Titicaca but only the Desaguadero River leaves it. Most of the water of the lake is lost through evapotranspiration. The lake has around 40 islands most of which are inhabited.
2. North America: Lake Superior
Lake Superior’s is North America’s biggest lake in terms of water volume. It is a freshwater lake on the US-Canada border. The lake is divided between the Canadian province of Ontario and the US states of Minnesota, Wisconsin, and Michigan. The volume of the lake is 12,000 cubic km that makes it the world’s third-biggest freshwater lake by volume. Over 200 lakes feed Lake Superior and the St. Marys River is its primary outlet. It is estimated that there is enough water in the lake to cover the entire landmass of the Americas to a depth of 30 cm. The lake has a maximum depth of 406 m. On July 30, 1985, an American limnologist J. Val Klump became the first person to reach the deepest part of Lake Superior which is 233 m below sea level. The waters here are very cold and is an almost constant 4 degrees celsius all year round. The temperature of the surface of the lake, however, varies seasonally. Twice in the year, the entire water column of the lake reaches a uniform temperature of 4 degrees celsius, a feature that makes the lake dimictic.
1. Asia: Lake Baikal/Caspian Sea
There is some confusion as to which is the largest lake in Asia. Although the Caspian Sea holds significantly more water than Lake Baikal, the former is often referred to as a sea rather than a lake as it is a remnant of the ancient Paratethys Sea. It became landlocked due to a fall in sea level and tectonic uplift millions of years back. However, others regard the Caspian Sea as a lake. Straddling the border between Europe and Asia to the east of the Caucasus Mountains, the Caspian Sea can be regarded as Asia’s largest lake by volume as it holds 78,200 cubic km of water. The Caspian Sea holds 40 to 44% of the total lacustrine waters of the planet.
Lake Baikal, the world’s biggest freshwater lake, is located in southern Siberia. Although it has a lower water volume than the Caspian Sea, it is sometimes regarded as Asia’s largest lake by volume as it is a true lake. 22 to 23% of the world’s freshwater is contained in this lake. Lake Baikal is also the world’s deepest lake and has a maximum depth of 1,642 m.