Welcome to brain Stuff from How Stuff Works. Hey, brain Stuff, Lauren Vogelbam. Here today we're talking about a rare but incredibly deadly natural phenomenon, exploding lakes a k A. Limnic eruptions. A limnic eruption is what happens when deadly gases like carbon dioxide explode out of volcanic lakes. Sometimes the carnage unfolds on multiple fronts. Just as lethal clouds suffocate humans and animals, the abrupt displacement of water is liable to
create tsunamis. That exact combination of events killed more than seventeen hundred people one grim summer day in nine six in the West African country of Cameroon. And now scientists wonder if an even bigger limnic eruption is in the making. But how does such an explosion happen? Let's start with water pressure. Water pressure increases with depth. That's why scuba divers can't venture too far below the surface without the
right equipment. The force that's exerted upon a submerged object by the weight of all the liquid above it is called hydrostatic pressure. Normally, this pressure intensifies by fourteen point five pounds per square inch or one kilo pascals or one bar for every ten meters of water depth. That's about thirty three ft. But the key to limnic eruptions lies in temperature. The gases dissolve more easily in cold,
high pressure water. Limnic eruptions can only occur in deep bodies of water with a lot of hydrostatic pressure at the bottom. There must also be a significant difference in both the pressure and temperature between the surface water and the lower depths, With the lower depths being much chillier. Stratification will act like a barrier, keeping that dissolved gas confined to the lake bottom, where it can't depressurize and escape out into the atmosphere. Because it's trapped, the dissolved
gas accumulates in massive and potentially deadly quantities. Explosions are impossible in lakes whose lower and upper water levels intermingle on the regular For build up to occur, the water also needs a continuous supply of some highly soluble gas, like carbon dioxide or methane, and that's where volcanism comes in. At localities with active volcanoes, buried magma is liable to send methane, CO two and other gases seeping up through
thin sections of Earth's crust. If a lake is overhead, the gas may pass right into the water, traveling by volcanic fence and other roots that brings us back to Cameroon and to its lakes. NEOs and Monoun both are located in a volcanic field, and both lake bottoms are oversaturated with carbon dioxide, which underlying magma sends their way. On August fifteenth, some of the deep water in Monoun that had been loaded up with the dissolved gas ascended
to the surface. No one knows why this happened. It's possible that heavy rainfall and an earthquake or landslide displaced some of the lake bottom water. Regardless, as the water rose, the dissolved carbon dioxide lurking inside it became depressurized and formed bubbles. Those bubbles drove even more of the water up to the top of the lake, resulting in a massive, foul smelling cloud of carbon dioxide gas. Under the wrong set of circumstances, this gas is extremely dangerous to people.
Large quantities of CEO to cling to the ground and displace oxygen, which can lead to death by suffocation. The eruption killed at least thirty seven people, and two years later, on August twenty one, six, Lake Neo's experienced a limnic eruption of its own. Once again, there was a sudden, mysterious upheaval of carbon dioxide laden water from its frigid, high pressure depths, but this time the body count was
much higher. Carbon dioxide from the Lake Neo's disaster killed approximately one thousand, seven hundred forty six people and more than three thousand, five hundred domestic animals. Somewhere from three hundred thousand to one point six million metric tons of c O two gas burst out of the water with enough force to set off a twentys tsunami that's about sixty six ft tall. That was the last recorded limnic eruption.
If you're worried about a killer limnic eruption coming to a lake near you, University of Michigan geoscience professor yolks Jung says you probably shouldn't be. Lake NEOs and Lake Monoon are located just above the equator, where it tends to be warm all year round, and there's just no way for a limnic eruption to happen in a temperate
body of water. In places where seasonal temperatures vary widely, like in the Great Lakes, lake surfaces often cool down, causing the water at that level to sink and swap places with the layers of water beneath it. Any gas is dissolved in there don't stay trapped. They're released as
they depressurized nearer to the surface. No gas accumulation, no eruptions. However, Young and many of his colleagues have taken a healthy interest in Lake Kivu, an up and coming vacation destination on the border of Rwanda and the Democratic Republic of the Congo. Why because it seems to have all the
necessary criteria for a truly colossal limnic eruption. The lake contains about ten point five billion cubic feet of carbon dioxide that's about three billion cubic meters, and two billion cubic feet of methane about up sixty billion cubic meters, all lurking near the bottom. Were those gases to explode from the lake's surface, the two million people who live around Kivu might find themselves in jeopardy. One possible solution though, harvest those very gases as a possible energy source by
an extraction barge. Kivu Wat is a one of a kind, two million dollar facility that uses an offshore barge to draw up water from the lake. It then siphons off the methane and sends it to a power plant, generating electricity for the area. When life gives you lemons, turn it into electricity. Today's episode was written by Mark Mancini and produced by Tyler Clang. For more on this and lots of other powerful topics lurking in the depths, visit our home planet has Stuff works dot com.