Exploding Lakes: Less Fun Than They Should Be

So I was going to write a post complaining about Daylight Saving Time and how I hate the darkness but then I realized that I do that every year and you are probably as sick of hearing about it as I am of having to live with it. And I also promised to write about exploding lakes quite some time ago and as I was reading a little more about them I realized that my first world problems kind of pale in comparison. So I will just say that if you are interested in learning about the cost benefits (or lack thereof) of DST, you can watch this interesting video here.

Now on to the lakes. When you hear the term exploding lake, you might picture something a little like this:

But actually, it looks a little more like this:

Sort of. Those are actually before and after photos of Lake Nyos in Cameroon, one of only three lakes in the world know to have the potential to "explode." There are two others in equatorial Africa and all three are known as limnically active lakes. (That's sciencespeak for "exploding").

What happens in a limnically active lake is that carbon dioxide (CO2) from rotting materials, such as occur at the bottom of a lake, or from another source such as a volcanic vent, dissolves in the deepest coldest layers of the lake. The pressure from all the water on top keeps it there where it builds up and builds up. Eventually the lake gets so saturated with dissolved CO2 that when something disturbs it (like a landslide or an earthquake) it bubbles out of solution and escapes to the surface forming a giant deadly cloud and you get yourself an exploding lake.

This is only known to have happened twice in modern history, both times in the 1980s. The first was at Lake Monoun and the gas cloud that arose from the lake killed 37 villagers and countless livestock in the surrounding area. The second explosion at Lake Nyos was even more deadly, killing between 1,700-1,800 people.

Perhaps the scariest part was that nobody really knew what happened. A giant cloud from the lake descended on the valleys below and everyone in its path lost consciousness. When the survivors awoke they found their neighbors and animals dead and the normally placid blue lake a frothy brown.

The government at first suspected terrorism but the numerous geologists arriving from all over the world put that theory to rest and figured out about the CO2. They also came up with some pretty ingenious solutions to prevent future eruptions. They installed CO2 monitors around the lake attached to alarms and told the villagers that if the alarms ever sounded they needed to get to higher ground as quickly as possible. They also installed a giant straw (basically) in the lake that brings CO2 rich water to the surface so the pressure doesn't keep building up. So far there haven't been any recurrences, though it would likely take quite a while longer for enough CO2 to build up again for another explosion anyway.

You may be wondering what you should do to protect yourself from the body of water nearest to you, but you shouldn't worry. Lakes in areas where the temperature fluctuates throughout the year naturally de-gas themselves. The water at the surface gets colder and heavier and sinks to the bottom, displacing the CO2 saturated water at the bottom and bringing it to the surface where it dissolves into the air. So I guess we should count our blessings that Daylight Saving Time, though annoying, is at least not deadly.