Discovered by chance: Limnic Eruption!!!
Today is the end of my geography presentation! And the end of all presentation for the whole semester!!! LIKE FINALLY!
Anyway, while I was doing my research for my geography project, I happen to come across a natural disaster that I never heard of and I think it is a very interesting yet unusual natural disaster too! (Although sounds weird to say that a disaster is very interesting yet unusual but I cannot find any other words to describe it!!)
So what is the natural disaster that left an impression on me is the Limnic Eruption.
What is a Limnic eruption?
A limnic eruption occurs when a large bubble of gas is trapped at the bottom of a lake and then get released. It reaches the top, explodes outward, and then travels down the slopes, suffocating everything in it's path. No smoke, no fire, no ash, no lava...no heat! It's just a whole bunch of gas getting released all at once. So how much gas are we talking about? The Lake Nyos eruption released 80 million cubic meters of CO2. (Information from http://mivo-sys.tripod.com/limnic.html )The following is a presentation slide on the Limnic Eruption that I have gotten from the following website,
http://www.powershow.com/view/12b03d-MTVkY/Limnic_Eruptions_flash_ppt_presentation
After watching reading the presentation slides provided, we know that the Limnic Eruptions is very rare, however, there has been 2 known cases:
- In Cameroon (A country in west central Africa), at Lake Monoun in 1984, causing the asphyxiation and death of 37 people living nearby. (* Asphyxiation: A condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally.)
- At neighbouring Lake Nyos in 1986, this time releasing over 80 million cubic meters of CO2 and killing between 1,700 and 1,800 people, again by asphyxiation
Lake Nyos scenic view before the Limnic eruption
(Image from: http://www.geo.arizona.edu/geo5xx/geos577/projects/kayzar/html/lake_nyos_disaster.html )
Lake Nyos view after the Limnic eruption
(Image from: http://en.wikipedia.org/wiki/File:Lake_nyos.jpg )
What method was used to prevent future eruption?
Method: Degassing
(Information from: http://www.geo.arizona.edu/geo5xx/geos577/projects/kayzar/html/lake_nyos_disaster.html )
What is degassing?
The
method consists of a pipe set up vertically between the lake bottom and the
surface. A small pump raises the water in the pipe up to a level where it
becomes saturated with gas, thus lightening the water column; consequently, the
diphasic fluid rises to the surface. Therefore, once it has primed the gas lift,
the pump is not needed, since the process is self-powered: above the saturation
level, isothermal expansion of gas bubbles drives the flow of the gas-liquid
mixture as long as dissolved gas is available for ex-solution and expansion.
People degassing the Lake Nyos
Lake Kivu, a potential Limnic Eruption destination...
- One of the African Great Lakes
- 2,000 times bigger than Lake Nyos
- Located in a densely populated area of about 2 million people
- Has a potential trigger, Mount Nyiragongo, an active volcano that erupted in January 2002.
- Also located in an active earthquake zone and close to other active volcanoes.
But...
Luckily, it has not reached a high level of CO2 saturation yet but if it does, it could cause a even greater disaster!
You may say, the people can use the degas method too, but due to its size which is very huge, it would be very costly to degas due to the gas will also be much more.
Alright, hope that you have gotten some useful insights about this unusual yet very interesting disaster! Watch out for my next blog post possibly about the Italian Dioxin Crisis! ^^
Signing off,
Evee
My World, My Life, My Attitude, My Geography
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