PowerSwitch

This is quite smart

http://www.youtube.com/watch?v=H2mZyCbl ... ture=share

showing how CO2 levels have changed as measured at several places.

Awesome. Figures even climate change deniers can understand.

But will it change anything?

emordnilap wrote:Awesome. Figures even climate change deniers can understand.

But will it change anything?

Indeed, awesome graphics.

I particularly liked the ppm scale on the RHS. CO2 zooming up off the chart is so much more scary than just saying it's reached 0.040% by volume.

Yes, most people just don't realize how scary 0.04% ought to be, how it could spell the end of human civilization and a mass extinction event.

Great animation. Though not as scary as the figures in this article:

http://www.ias.ac.in/currsci/jun252006/1607.pdf

Kieran wrote:Great animation. Though not as scary as the figures in this article:

http://www.ias.ac.in/currsci/jun252006/1607.pdf

Having read it I'm not sure if they are being serious or not. CO2 increases in closed environments are always accompanied by a significant reduction in the level of O2 and an increase in humidity. Operating in a low O2 environment, regardless of the CO2 level, produces exactly those symptoms described.

Increasing atmospheric CO2 to 0.10% by volume will have no appreciable impact on the amount of O2 available unlike in a closed space where the O2 has become CO2.

I need to see results of an oxygen stable test before I became worried about breathing air with 0.050% CO2 by volume.

I wonder what CO2 volumes the indigenous Amazonian tribes work in?

JavaScriptDonkey wrote:

Kieran wrote:Great animation. Though not as scary as the figures in this article:

http://www.ias.ac.in/currsci/jun252006/1607.pdf

Having read it I'm not sure if they are being serious or not. CO2 increases in closed environments are always accompanied by a significant reduction in the level of O2 and an increase in humidity. Operating in a low O2 environment, regardless of the CO2 level, produces exactly those symptoms described.

Let me just check what you are claiming here. It look like you are saying that the symptoms (for humans) of a comparitively low oxygen environment are the same as those of a comparitively high CO2 environment. Or are you saying something else?

Yep. I had to look them up but they sounded familiar. At low levels the physical symptoms of hypoxia are,

headaches
fatigue
shortness of breath
feeling of euphoria
nausea
Hot and cold flashes
Visual Impairment

The physical symptoms (it doesn't say the subjects suffered from all these just that they started to exhibit some of these classic symptoms) cited in the closed room experiment for CO2 up to 1000ppm were ,

difficulty in breathing,
rapid pulse rate,
headache,
hearing loss,
hyperventilation,
sweating
fatigue.

I'm not doubting the veracity of acidosis it's just that the studies seem to indicate that the experimenters didn't differentiate between a high CO2 atmosphere and a low O2 one. If you just close the door on an airtight lab the occupants slowly convert the O2 to CO2, reducing one and increasing the other.

I'll be happy to be corrected - as I've said before, biology and chemistry are not my bag.

Perhaps there will be pertinent mortality data in the actuarial weightings for brewery workers and nurserymen?

I've checked some DODGY TAX AVOIDERS CO2 data and it is unlikely to be revealing as it notes CO2 variations from 350 - 577ppm at varying heights/locations over the course of a day.

The only difference I know of is that while excess CO_2 causes rapid breathing and general hyper-ness, lack of O_2, by itself, does not. Anyone else remember that clip in "The Body In Question" whrn Johnathan Miller demonstrated precisely that?

Suicide via a plastic bag filled with an inert gas appears to be a growing trend as it's rapid and painless. Seem to remember Michael Portillo investigating death in a tv programme a while back where they showed a clip of a cow with it's head poking through an airtight seal in a tent filled with an inert grass. It was eating some grass and carried on munching with no sign of distress until it passed out - then it was rescued, of course.

Edit: It was on the beeb and called "The science of killing human beings". Remembered it wrong: it was pig in a sealed room. Youtube clip here: http://www.youtube.com/watch?v=0EHXwyFhUXc

Prof Ian Stewart is doing an experiment where he is to be sealed in a box with some plants in the hope that they will generate sufficient O2 for him to survive.

It will be interesting TV when it airs.

Don't confuse Prof Ian Stewart the mathematician with Prof Iain Stewart the geologist.

Everyone knows Iain 'cos he's been on telly, whereas Ian is more often on Radio 4 therefore invisible.

And the pictures are better in geology than maths.