Actually it is toxic as humans will lose consciousness in an atmosphere containing 10%
CO2 and more will certainly kill. So you can have plenty of O2 present and still die. An
excess of CO2 like that would probably tie up sufficient hemoglobin such that O2
transport decreases greatly (Biochem 101 for the day).

I doubt if 100% displacement (density of CO2 in air vs O2 in air is only 1.53 vs. 1.50)
over such a large area could take place but more likely the %CO2 level rose above the
threshold level and the rest is history.

Regards

John Barnard

RHF wrote:

JB,

"I remember hearing about a village in Cameroon that was
essentially asphyxiated when a local volcano spewed out CO2
that blamketed the area. In that case, such a large quantity
of CO2 given off in a short period of time was toxic enough
to wipe out a village."

? TOXIC ?

In this case it is Oxygen Displacement
(The normal AIR Mixture is being Replaced by another Gas.)

Same thing happens in Grain Silos and old water wells.

Try working in a Room full of Freon Ultra-Sonic Cleaners.
http://inventors.about.com/library/i...rs/blfreon.htm

jtfm ~ RHF
.
.
= = = John Barnard
= = = wrote in message ...
Stuff snipped


What I wonder is why nontoxic CO2 is lumped with the toxic gasses that cause
even more problems with our climate. Maybe the world's population should be
reduced just to cut down on the amount of CO2 that is exhaled.


I remember hearing about a village in Cameroon that was essentially asphyxiated
when a local volcano spewed out CO2 that blamketed the area. In that case, such a
large quantity of CO2 given off in a short period of time was toxic enough to wipe
out a village.

There are a few good natural solutions to excess CO2 in the atmosphere. One is that
the bodies of water in the world can act as a CO2 sink. The other solution are
plants as they consume CO2 during photosynthesis. Maybe humanity should quit
deforesting at an ugly rate?


Here's the breakdown of Earth's atmospheric gases:

The atmosphere is primarily composed of Nitrogen (N2, 78%), Oxygen (O2, 21%),
and Argon (Ar, 1%). A myriad of other very influential components are also
present which include the water (H2O, 0 - 7%), "greenhouse" gases or Ozone (O,
0 - 0.01%), Carbon Dioxide (CO2, 0.01-0.1%).

Note that water vapor, also a greenhouse gas although not so noted in this list
I got off the Internet, averages many time greater than CO2.

Bill, K5BY

That's the crux of the matter. Water vapour is in much greater quantities than CO2
in the atmosphere and does have an obsrvable day-to-day effect on local
temperature. If you were to compare equal quantities of water vapour and CO2 then
CO2's efficiency as a greenhouse gas becomes quite a bit greater than water vapour.

Regards

John Barnard

Thanks for the correction! My daily dose of the BBC brought that particular item to my
attention.

Regards

John Barnard

N8KDV wrote:

RHF wrote:

JB,

"I remember hearing about a village in Cameroon that was
essentially asphyxiated when a local volcano spewed out CO2
that blamketed the area. In that case, such a large quantity
of CO2 given off in a short period of time was toxic enough
to wipe out a village."

It was not a volcano, but rather a volcanic lake. On 21 August 1986, Lake Nyos in
Cameroon suffered a landslide which triggered the release of CO2 which was trapped under
the lake.

Approximately 1700 people were killed.

There are apparently a good number of other lakes around the world where this phenomenon
could occur again.

Just to keep things in perspective, I recall hearing about this incident while monitoring
shortwave!

Steve
Holland, MI
Drake R7, R8 and R8B
"I swear by, not at, Drake receivers" ©

http://www.iserv.net/~n8kdv/dxpage.htm