First, do you know that carbon dioxide (CO2) in our atmosphere is:

--only slightly more than 1/3rd of 1/10th of 1 percent?
--just recovering from the lowest level in the history of the earth?
--the source of carbon for all life forms, on land or in the sea?
--only slightly above the suffocation level for green plants?
--a fraction of the level for which evolution designed plants?
--so low as to cause some people breathing problems?
--increased by 130 times and more when administered to sick patients?
--considered a pollutant by the U.S. Supreme Court?

Over the last 350 million years CO2 has varied by 10 fold, approximately 250 ppm to 2,500 ppm with an average level of 1,500 ppm. This average level happens to be the optimum level for plants, it seems by evolutionary design, and is the reason that this level of CO2 is used in greenhouses Since plants and animals evolved together it's likely that humans also evolved to function best at some higher level. However, at 380 ppm we are not far from the lower end of that 10 fold range.

Has anyone heard this before? It's copied from a reliable source, but there wasn't any attribution.

 

--only slightly above the suffocation level for green plants?

That sounds like green plants would be suffocating if the level is above their suffocation level. Am I reading this wrong?


...And I haven't heard this before but it's not the kind of thing I'd be looking for.

 

did you know that solid CO2 better known as dry ice, will extract the water from an alcohol / water / fruit juice solution resulting in a much higher concentration of alcohol in the mixture?

on campus they referred to this particular form as a hairy buffalo.

 

Then how can it be reliable? Even, "As spoken by Fred at CPAC" would give it some recognition.

 

 

Since plants take in CO2 and strip the carbon atoms to exhale oxygen this makes sense. It is like saying that the level of oxygen in the atmosphere is just above suffocation level for people. If it were lower we would suffocate.

 

Ah, thank you, tof.

 

Ummmm, not so much really. http://en.wikipedia.org/wiki/File:Co...ature-plot.svg

 

Did you all know that space aliens have visited us hundreds of times in the past year?

I heard it from a reliable source, but I don't have any attribution....

Cordy's "facts" are the usual mishmash of some things outright wrong, some things true but distorted in meaning, and some things true tossed in as cover to make the rest of it more palatable.

 

Building inspectors think this:

A factor of 130 increase from ambient yields a 5.2% CO2 fraction.

I guess those patients who get this are maybe the ones on death row?

And, given the plot that Mike pointed to, how come all the plants (for which current ambient CO2 levels are near the "suffocation" threshold) didn't die several times over when the level was down around half the present amount? (For all of you who are getting the winter grays and browns, take it from me -- there's lots of green out there.)

How crap like this is thought to be credible just amazes me -- or maybe not, given the source in the internet rumor mill and how it wound up here.

And ...
"Just above"?

In the foothills west of Denver, there's about 80% as much oxygen as at sea level. People of all ages live there quite happily. A few miles north, on top of Long's Peak, there's about 60% as much oxygen as at sea level. It's a bit of a climb, and almost anyone will be breathing hard at the top, but no one "suffocates."

Credibility seems to be hard to come by these days.

HPH