A debate recently broke out among a couple of my daughter’s friends. Or, perhaps debate is too strong a word – a question was posed, and the answer was elusive. And it turns out that the answer to their particular question is elusive. They were on the right track, but hadn’t arrived at the right answer. Or answers.
But that’s what happens when you start talking about the world’s largest lake.
We were spending an afternoon on the beach (or what’s left of the beach during this current high-water phase) of Lake Michigan, often regarded as the second-largest of the Great Lakes. And that’s as good as anywhere to start.
So, since we still haven’t received any new questions [Please Send Questions!] I’ll go ahead and “submit” the great lake debate for this week’s edition of “Water We Talking About?”
What is the biggest lake in the world? – Lincoln (11) and Will (10)
Thanks for kicking off this discussion guys! To begin to answer the question, though, we have to define how we’re going to measure size. If you are talking about the lake with that holds the most water, then you need to head to a place in Russia just north of its border with Mongolia, where the crystal-clear waters of Lake Baikal plunge down more than a mile to a lake floor formed at the intersection of two continental plates. This depth allows Lake Baikal to hold a ton of water. In fact, more than 20% of all the available freshwater on Earth is stored in Lake Baikal. Lake Baikal is also the oldest and clearest lake in the world, so it’s tops in a lot of categories. However, when it comes to the amount of space its surface takes up, Lake Baikal isn’t even in the top 5.
The largest lake in the world by surface area is Lake Superior. The surface of Lake Superior covers 31,700 square miles! That’s more space than the states of Vermont, New Hampshire, Massachusetts, Rhode Island, and Connecticut take up – combined. And Lake Superior is no slouch when it comes to volume either. It alone holds 10% of all the freshwater in the world and that’s enough to cover North and South America in a foot of water.
So, in a line-up of the usual lake suspects, Lake Superior is the biggest by surface area and Lake Baikal is the largest by volume.
But here’s where things get interesting.
After you’ve decided what measurements to use to determine “biggest,” you then have to ask yourself an even harder question – what is a lake?
Take Lake Michigan for example. We all know that there are 5 Great Lakes (Superior, Michigan, Huron, Erie and Ontario). But did you know that Lake Michigan and Lake Huron are technically one lake? Their entire basin is connected by the Straits of Mackinac at the tip of Michigan’s mitt, meaning that there isn’t a complete land barrier between the them – they’re really one body of water.
So, if you consider Lake Michigan and Huron a single lake (Michuron?), suddenly there’s a new leader in the race for the surface area crown. Added together, the surface of the two lakes cover 45,000 square miles.
That said, they still wouldn’t hold as much water as Lake Superior and come in far distant from Lake Baikal.
But wait, there’s more!
If you’re willing to accept a slightly different definition of a lake, then there is one body of water to rule them all. It covers nearly 5 times as much surface area as Lake Superior and holds more than 3 times as much water as Lake Baikal.
The catch is that that water isn’t fresh, it’s salty. And this inland body of water is is more commonly called a sea, the Caspian Sea to be precise.
Unlike the other lakes on this list, the Caspian Sea doesn’t sit in a basin that is entirely on continental crust, which is a function of its being connected to the ocean millions of years ago. But, despite that past, the Caspian meets most modern day requirements for being a lake so, if we’re strictly being scientific, then there really is no debate – it is the largest lake in the world by any measurement!
Thanks for tuning in. We’ll be back with Water We Talking About, our a series where kids send us freshwater-related questions and we track down a (usually) freshwater answer, next week. This week our question was overheard, not outright asked. So, to keep us from eavesdropping on more kids’ questions, why don’t you have a kid you know send one our way? Here’s how!