The comparative limnology of lakes nyos and monoun. On august 21, 1986, a rare natural disaster occurred in the west african country of cameroon when a large cloud of carbon dioxide gas spewed from lake nyos and blanketed nearby villages killing 1,746 people and 3,500 livestock while they slept the event, known as a limnic eruption, occurs when carbon dioxide builds in colder, deep lake water creating a heavy. Lake nyos suffocated over 1,746 people in a single night. Lake nyos degassing process 90% complete journal du cameroun. Research news opinion research analysis careers books and culture podcasts videos. For lake nyos the model included one additional pipe installed each year starting in 2005 for a total of five pipes in the lake by 2008, and the inlet depth for all pipes was at 206 m. Though not completely unprecedented, it was the first known largescale asphyxiation caused by a natural event.
Ephriam che was in his mudbrick house on a cliff above nyos, a crater lake in the volcanic highlands of northwest cameroon. Scientists from the united states, france and cameroon are using a series of giant pipes to release carbon dioxide from deep down in the waters of the lake. Nov 15, 2008 this is a great way to show students that carbon dioxide gas is heavier than air. Lake nyos disaster survivors to return home after 30 years duration. Oct 04, 2005 to evaluate the effectiveness of other degassing configurations, we modeled the impact of adding more pipes to the lakes. Recent ph and co 2 profiles at lakes nyos and monoun. In the 1980s, limnic eruptions occurred at two crater lakes, lake nyos and lake monoun, in which. At lake nyos, the gas was released suddenly, at a single site, and remained highly concentrated. Download premium images you cant get anywhere else. Degassing the killer lakes thorough investigations of the physics and chemistry of lakes monoun and nyos quickly revealed that both lakes still contain huge amounts of carbon dioxide 10 millions m3 and 300 millions m3 in monoun and nyos, respectively and that this gas is being added at such a rate that saturation could be reached within years in the deep layers of the lakes.
Lake nyos lies within the oku volcanic field, at the northern boundary of the cameroon volcanic line, a zone of volcanoes and other tectonic activity that extends southwest to the mt. Lake nyos, cameroon, shows red coloration from iron oxides stirred up by the artificial degassing of carbon dioxide from the bottom water. In 1986 lake nyos, a deep crater of water high on the flank of an inactive volcano in northwest cameroon literally exploded, flipped over and sent deadly waves of noxious carbon dioxide across the surrounding hills and valleys. Lake nyos is roughly one square mile in surface area, with a maximum depth of 690 feet. Read recent ph and co 2 profiles at lakes nyos and monoun, cameroon. Worlds best lake nyos stock pictures, photos, and images. A volcanic dam impounds the lake waters a pocket of magma lies beneath the lake and leaks. Late on the evening of thursday 21 august 1986, a deadly cloud of gas swept along the valleys north of lake nyos in western cameroon, leaving a trail of death and devastation in its wake. Degassing the lake was suggested immediately after the lnd and was followed up with studies investigating the safety of possible procedures and. Dead cattle surround compounds in nyos village sept. This paper describes the main findings encountered during the degassing project, some relevant technical issues observed during the last 5 years 20142019, and lessons learnt from the guadiana pit lake experience.
Prev next after lake nyos burst, an international team began discussing ways to degas both lakes and avert future disasters. Before the initiation of degassing, gas saturation reached the critical level of 97% at 56m depth in lake monoun, and lake nyos water was up to 73% saturated at 206 m. Based in part on eyewitness reports made to an international team of volcanologists and biologists that visited the site, the event was initiated by a very. Ppt lake nyos powerpoint presentation free to download. An international team of scientists has begun work on siphoning toxic gas from a volcanic lake in northwestern cameroon. A magma chamber beneath the lake is an abundant source of carbon dioxide, which sweeps up through the lake bed, charging the waters of lake nyos with an estimated 90 million tonnes of co 2. The lake nyos limnic eruption was located in the northwest region of cameroon, africa. Pdf decreasing capability of the degassing systems at lakes. For one thing, lake nyos sits on top of a volcanic hotspot, formed in the crater of a fourhundred year old explosion. They talked about bombing the lakes to blow out the gas. For most volcanic lakes, the degassing takes place gradually without great risk of a catastrophe.
The muddy materials likely contain a large proportion of. Piping of anoxic, hightds bottom water to the lake surface has had a complex effect on the mixolimnion. A video camera sent to the bottom of the lake stirred the muddy sediments fig. A degassing system has since been installed at the lake, with the aim of reducing the. Lake nyos is a crater lake in the northwest region of cameroon, located about 315 km 196 mi northwest of yaounde. The onedimensional twofluid model is applied to the simulation of the degassing devises installed in lakes nyos and monoun respectively in 2001 and 2003. The lake nyos disaster, which killed an estimated 1250 people on the 21st august 1986, was caused by the release of a toxic aerosol of water and carbon dioxide. Lake nyos is a crater lake in the northwest region of cameroon, located about 315 km 196.
Evolution of co2 in lakes monoun and nyos, cameroon. On august 21, 1986, possibly as the result of a landslide, lake nyos suddenly emitted a large cloud of co 2, which suffocated 1,700 people and 3,500 livestock in nearby towns and villages. By martin schmid, michel halbwachs and alfred wueest. Therefore, even after jet grouting and degassing, the problem of risk minimization for local residents remains. This latter contains a thousand times more gas than lake nyos. Two additional degassing pipes were added at lake nyos in late 2011 and early 2012 using funds from the eu to increase the degassing rate, and the water intake depth was deepened to 207209 m, only a few meters above the lake bottom. Nyos is a deep lake high on the flank of an inactive volcano in the oku volcanic plain along the cameroon line of volcanic activity. This is quite unusual for lakes and is due to a unique conflux of geologic factors. Its situated in northwest cameroon, around 30 miles from the nigerian border to the north. More than 1,700 died when lake nyos erupted in 1986. The larger pipes will serve as a regulating system in the future.
They say that pressure from the gas has built up again and a similar tragedy could happen at any time. A free powerpoint ppt presentation displayed as a flash slide show on id. Farmers and migratory herders in the west african country of cameroon knew the lake as large, still and blue. Lake nyos silent but deadly volcano world oregon state. The dissolved co2 is seeping from springs beneath the lake and is trapped in deep water by the high hydrostatic pressure. The lake is compositionally stratified, with fresh water occupying the upper 50m and heavier sodium and carbon dioxide rich water below that. Lake nyos in 2001 and at lake monoun in 2003 under nmdp, funded by the u. On august 12, 1986, lake nyos, cameroon, had a sudden release of about 1 km3 of co 2 gas. More than 1,700 people died after deadly gases spewed from lake nyos 15 years ago. The 1986 lake nyos gas disaster in cameroon, west africa.
Final step of the 32year lake nyos degassing adventure. After a 28year operation of the nyos organ pipes in hindsight, we can highlight some of the main findings of the program pertaining to the lake nyos syndegassing evolution. The true killer was identified as a strange volcanic phenomenon associated with the nearby lake of nyos. People living around lake nyos may finally start feeling safer when two degassing pipes start pumping 600,000 tons of carbon dioxide out of the lake in february, a process that is expected to run up to 2014. The strange lake nyos co2 gas disaster massey university. When they came out of their houses to see what was amidst, they were suffocated by a gas that emanated from the lake. On 21 august 1986, a limnic eruption at lake nyos in northwestern cameroon killed 1,746. Lake nyos is a crater lake located in the northwest province of cameroon. On august 21, 1986, the carbon dioxide at the bottom of the lake suddenly erupted all at once, 1. In 2010 two more degassing pipes were added to lake nyos the three pipes now operating can be seen in the picture at the left. Because the 3 pipes are bringing up large amounts of ironrich bottom water along with the dissolved gas, the lake has again turned red, just like it did right after the 1986 explosion. Scientists reasoned that co 2 had been trapped in the bottom of lake nyos for a long time, held down by 682 feet 208 meters of water.
Abstract 1 a large gas cloud erupted unexpectedly in 1986 from lake nyos, the larger of the two cameroonian killer lakes, with devastating consequences. Hydrodynamics of the water and gas jet that initiated the. Geosciences free fulltext lake nyos, a multirisk and. Before this, the co 2 was held under pressure at the bottom of the lake. Lake nyos is an active crater lake that formed by a volcanic eruption about 5 centuries ago. Degassing may render lake nyos safe cameroonpostline. The blue appearance of lake nyos before carbon dioxide degassing left and the brown appearance after the lake degassed and is saturated with carbon dioxide right. A new gas removal system applied to lake monoun to prevent a future limnic eruption. The resolution of the conservation equations of the multiphase system makes it possible to describe the twophase gasliquid flow parameters along the degassing riser. Recently, the national emergency management agency nema has draw the public attention to the imminent collapse of the lake nyos by 2015 as anticipated by the agency. Enrichment of ferrous iron in the bottom water of lake nyos.
It was one of the most unusual and destructive natural disasters in modern times. Magmatic fluid supply into lakes nyos and monoun, and mitigation. At sunset on august 21, 1986, inhabitants mostly farmers and herders of the neighbourhoods of lake nyos in menchum division of the then northwest region of cameroon, heard a loud rumble from the lake. In any case, we conclude that the burden of degassing lake nyos will be increasingly borne by column c2001.
Following the lake nyos disaster, scientists investigated other african lakes to see if a similar phenomenon could happen elsewhere. Cattle suffocated by carbon dioxide from lake nyos wikimedia commons. Lake nyos degassing degassing the killer lakes nyos. Find highquality lake nyos stock photos and editorial news pictures from getty images. Remote work advice from the largest allremote company. Webster states that a disaster is a sudden calamitous event bringing great damage, loss, or destruction. Large fountain from a co2 degassing pipe in lake nyos. Lake nyos science and a killer lake background lake nyos lies in an old volcano crater maar in cameroon, a country of africa.
The bottom of lake nyos is covered by soft sedimentary materials. The rocks here are actually still active, although you wouldnt guess it from the surface. But scientists worried a bomb would also blow out one of lake nyoss walls, causing an enormous flood. Visiting deadly lake nyos dark tourism in africa dark. Lake nyos is the most renowned of the numerous maars and basaltic cinder cones associated with the deeply dissected mount oku massif. Diagram illustrating the flow of carbon dioxide gas from lake nyos. More than 1,700 people were killed in cameroon after being poisoned when a huge bubble of carbon dioxide gas erupted from lake nyos in.
Starting from 1995, feasibility studies were successfully conducted, and the first permanent degassing tube was installed at lake nyos in 2001. Jul 12, 2004 on august 21, 1986, a large quantity of water and gas, mainly co 2, was released from lake nyos in cameroon, leading to the deaths by asphyxiation of more than 1700 people, freeth and kay 1. On the evening of 21 august1986, a tremendous explosion of co2 from the lake nyos, west of cameroon, killed more than 1700 people and livestock up to 25 km away. The degassing techniques and construction of the degassing system are described in halbwachs et al. The pipe installed in lake nyos is powered by natural levels of carbon dioxide. There are three lakes in the world containing a high proportion of dissolved gas. Visiting the most deadly lake in the world is on my bucket list of dark tourist destinations. Pick one of the following disasters to research and become part of through story.
To watch the full lengthdownload the voeh video player here. Decreasing capability of the degassing systems at lakes nyos and monoun cameroon. After lake nyos burst, an international team began discussing ways to degas both lakes and avert future disasters. Defusing africas killer lakes science smithsonian magazine. Above all, the reintegration program has provision for the complete degassing of lake nyos with the installation of two more pipes each of which has the capacity that is four times that of. The most disastrous co 2related incidents have occurred near lakes that have very high levels of co 2 at depth. Prof michel halbwachs and his frenchcameroonian team, on the road to success. Degassing the killer lakes nyos and monoun, cameroon. Lake nyos is located along the cameroon volcanic line cvl, a 950mile long chain of volcanoes and volcanic crater lakes extending from. At lake nyos, and a few years earlier 1984 at lake monoun nearby, the sudden release of massive amounts of carbon dioxide from the lake bottom displaced oxygen along the shore villages suffocating people and animals. Lake nyos is located in the cameroon volcanic line, a 950 mile long chain of volcanoes and. Office of foreign disaster assistance usaid and the cameroonian and french governments. Modelling gasliquid flows in degassing risers used in.
A volcanic dam impounds the lake waters a pocket of magma lies beneath the lake and leaks carbon dioxide co 2 into the. Degassing lake nyos in the middle of an august night in 1986 in the westafrican country of cameroon a misty cloud of carbon dioxide bubbled out of a lake and swept silently down the surrounding valleys thousands of animals and 1700 people died, many in their sleep. The killer lakes of cameroon university of michigan. Lake nyos is stable, under normal circumstances, despite being highly charged with carbon dioxide, as it was both before and, to a lesser extent, after the disaster. Lake nyos in north west cameroon managed to kill over 1,700 people and 3,500 livestock in a single night. The april 1996 ctd measurement was also taken during his mission to lake nyos. In the wake of the tragedy, a number of plans have been proposed to ensure lake nyos never erupts. It is unknown what the trigger wasit may have been a landslide, small volcanic eruption, or even something as small. The most affected villages of this disaster were cha, nyos, and subum.
It also helps them understand the unusual natural disaster at lake nyos in africa. Lake nyos in cameroun is an inactive volcano crater lake that was formed by an eruption about 5 centuries ago. Lake nyos killed 1,746 when it released a huge pocket of co2. To evaluate the effectiveness of other degassing configurations, we modeled the impact of adding more pipes to the lakes. Oct 21, 2015 lake nyos disaster survivors to return home after 30 years duration. On the day of the eruption, however, something external triggered the release of gas. Ppt lake nyos volcano powerpoint presentation free to. Rather than releasing the gas, the lake was acting as a highpressure storage unit. The controlled degassing is continuing at both lakes.
This is a great way to show students that carbon dioxide gas is heavier than air. National geographic documentary video about the process of investighation of the limnic eruptions at lakes monoun and nyos. The mixolimnion encompassed the upper 4050 m of lake nyos and upper 1520 m of lake monoun prior to the installation of degassing pipes in 2001 and 2003, respectively. Lake nyos is roughly one square mile in surface area and has a maximum. The strength of layering and stability in the lakes remains high, indicating that the gas removal is not destabilizing the lakes, and is not increasing the likelihood of another disaster. Mitigating the hazards of lake nyoss collapse corpers diary. Lake nyos disaster survivors to return home after 30 years youtube. Simulation of co2 concentrations, temperature, and stratification in lake nyos for different degassing scenarios. The process of degassing lake nyos is 90% complete and government is stepping up efforts to have it completed. Environmental education resources to commemorate earth days 50th anniversary. Why this lake is the deadliest in the world duration.
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