A “lake” is a body of water surrounded by land that is deep enough that sunlight doesn’t reach the bottom (a “pond” is a body of water shallow enough that sunlight reaches the entire bottom and photosynthesis can occur on the bottom).

According to National Geographic, there are about 117 million lakes in the world and they cover about 4% of the earth’s surface in aggregate.

By the way, if I were to form an indie rock band I’d either name it “Subsidence Event” or “Deep Lake Explorers.”

The World’s Deepest Lake

At 5,387 feet deep, Lake Baikal in Southern Russia is the earth’s deepest lake. That is really deep! Keep in mind that a mile is 5,280 feet. Some other Lake Baikal facts:

• It is 395 miles long, averages 30 miles wide and its surface is 12,200 square miles. Its shoreline is about 1,300 miles (not that a shoreline can be measured with accuracy). That’s a big lake!

• Lake Baikal’s large surface area and incredible depth combine to make it the earth’s largest freshwater lake by volume as well. It holds so much water that about 1/5th of all the freshwater on the earth’s surface is in Lake Baikal!

• Lake Baikal wasn’t created via erosion — as is the case for most lakes — but rather due to a “continental rift” which occurs when the earth’s tectonic plates move apart. The Baikal rift zone is still active with the plates moving apart at a rate of about 1 inch per year. As the rift widens the lake gets deeper.

• At about 20 million years old, Baikal is also the earth’s oldest lake.

Deep Lakes in the U.S.

At 1,949 feet deep, Crater Lake in southern Oregon is the deepest lake in the U.S. and the ninth deepest lake in the world. It is the caldera of a volcano that erupted 7,700 years ago. Crater Lake has no streams running in or out of it. The water in the lake is the result of a lot of precipitation.

The second deepest lake in the U.S. is Lake Tahoe. It is 1,645 feet deep. It was created through faulting when movement of tectonic plates created the Sierra Nevada range and the Carson range and then lava flows forming a natural dam — Lake Tahoe sits between the two ranges. The water in the lake is quite cold – averaging about 39 degrees Fahrenheit.