Minimum Atmospheric CO2 percentage for plant life!

[John Brown]

What utter pineapples...!!

ETA: The auto censor didn't allow me to express myself adequately in response to
the nonsense in the quoted post above.

Please expand. I'm not doubting you, or taking sides, but would be interested in the nitty gritty.

 

[Jacob]

What utter pineapples...!!

ETA: The auto censor didn't allow me to express myself adequately in response to
the nonsense in the quoted post above.

@Gant is not that far off!
Read all about it, @Gant obviously has! Helium - Wikipedia

 

[Molynoox]

@Gant is not that far off!
Read all about it, @Gant obviously has! Helium - Wikipedia

That's such a generic link it's almost pointless Might as well have provided a link to Google.

 

[Jacob]

That's such a generic link it's almost pointless Might as well have provided a link to Google.

What, you knew all that stuff already?

 

[Molynoox]

What, you knew all that stuff already?

That's not what I said, meant or implied.

 

[Jacob]

That's not what I said, meant or implied.

What did you mean then? The info more or less matched Gants ramblings. Perhaps not the helium balloons and the MRI scan bit.

 

[Daniel2]

Please expand. I'm not doubting you, or taking sides, but would be interested in the nitty gritty.

I was referring to the suggestion that party balloons have an impact on the number
of MRI scans that can be performed.

 

[Jacob]

I was referring to the suggestion that party balloons have an impact on the number
of MRI scans that can be performed.

Yes that was a bit of an extrapolation!

 

[Molynoox]

What did you mean then? The info more or less matched Gants ramblings. Perhaps not the helium balloons and the MRI scan bit.

I've already explained what I mean. Read it again maybe? I could expand but I think it would be patronising as it's pretty succinct already.

 

[sawtooth-9]

Here is something to ponder, has the total mass of water on Earth changed over time. It might have changed state from warm seas to ice but is Earth a closed system so apart from a small amount lost by astronaunts then we are actually drinking dinosaur urine. If this is the case then total amounts of Co2 and Methane may not have changed mass, they were just stored somewhere following Earths volcanic and turbulent past so it is us who has released them but without means to store them again. This means that rising sea levels are catastrophic because we live here, but it just means we could end up back in a previous period of Earths history where it was just water.

https://astronomy.com/news/2020/03/ancient-earth-may-have-been-a-water-world-without-any-dry-land

Assuming the Earth is a closed system it does not follow that the total amount of water is fixed. So too with CO2 and methane ( CH4 )
It more likely follows that the total number of individual atoms which make up these compounds remains constant.
Carbon, hydrogen and oxygen compounds can break down and reform into different compounds by a whole variety of mechanisms e.g cows eat grass and from this raw material they produce methane.

 

[mwinfrance]

It more likely follows that the total number of individual atoms which make up these compounds remains constant.

Oh Dear...someone skipped biology, chemistry and physics..probably maths too.

It is a lot more complicated than "atoms" and "compounds" ..much more to do with energy.

 

[conrad]

There are medical grade gases, so you are correct. Oxygen is a good common example where you get the oxygen bottle for welding and there is the medical grade for respiration so filling ballons with the more expensive grade of Helium would not make sense.


When you look around at woodworking machinery there is nothing not made or assembled from parts from Asia so there is no choice. The days of buy British went with the demise of the british manufacturing industry when someone pulled the flush.

There have been several threads with regards to asian goods and quality, the reason we get a bad impression of say Chinese quality is because our machinery companies like Record and Axminster are in control of the price they wish to pay to maintain their profit margins so it is us who are wanting lower cost goods that are influencing the quality. To highlight Chinese technology, if anyone saw the news the other night where the Chinese were playing so called war games around Taiwan you must have seen that there military is on par with anyone else when it comes to technology, replace the chinese people and you would have thought it was an American war game.

I agree with you Spectric.

I don't actually have a problem with Asian manufactured goods, but I do prefer to buy goods that are made closer to home if I can. In my case, just for environmental and economic reasons.

I just don't have an appetite for suppliers who sell goods that suggest they are somethig other than what they are.

 

[sawtooth-9]

Oh Dear
My degree is in Chemistry, physics and pure maths
You might like to re-think your comment.
Provide a rational argument rather than try to denigrate the messenger - they might just be more informed than you think.

Oh Dear...someone skipped biology, chemistry and physics..probably maths too.

It is a lot more complicated than "atoms" and "compounds" ..much more to do with energy.

 

[Fitzroy]

I was chatting carbon cycles with someone the other day and realised I was talking based on my education from 30yrs ago, got me wondering what I’d forgot and what had changed. In my research I came across the following graphic that I thought excellent.

I found the mass of carbon stored in each ‘realm’ very interesting and something I had no knowledge of. It does not include that stored in rocks, which holds 99+%of earth’s carbon. It shows the incredible role both the ocean and biomass are playing to soak up a good portion of the extra carbon entering the atmosphere. I’d not really thought that stuff would be growing faster (now how you measure that must be complicated!).

Fitz

 

[Alex Podut]

It’s something I hadn’t thought about, but it’s a question provoked by being asked what is the present concentration of CO2 in the atmosphere and what was it 150 million years ago, in the middle of the period when the dinosaurs roamed the Earth. The answers are for me very interesting.

What percentage of the atmosphere is CO2? Well I thought it must be something like 5 or 10%! No, it’s actually 400ppm or, 0.4%!

Plants actually die if the level of CO2 in the atmosphere drops too much, it it gets down to around 250ppm or 0.25% they stop photosynthesis and start to die! Plants thrive in much higher CO2 concentration, their ideal is around 3000ppm or 3%. They also become more drought hardy!!

Finally, in the middle of the era when the largest animals to ever exist were plodding around, in a lush green environment the level of CO2 was over 3000ppm or 3%, the ideal levels for plants! and 750% higher than today.

So, when I hear about thermal runaway of the atmosphere, we are all doomed, it seems rather strange when the world not only survived but thrived with massively higher CO2 levels. Why doesn’t this ever feature when we talk about climate change?

Small correction... 400ppm (parts per million) mean 400 parts / 1 million parts = 400/1000 000 = 0.00004
(mod edit, no it isn't, it's 0.0004)
In percentage that is 0.00004 × 100 = 0.04%
(mod edit, maths wrong again but at least the final percentage is right
(mod edit, come on you guys, check your maths. If you were both making x10 errors in your personal finances you'd soon feel it).

 

[SammyQ]

As Alex P. says above, 0.04%. It has risen, in my lfetime, from 0.03%. I am utterly shocked that - in three pages of entries in this thread - no-one, but no-one has corrected Deema's wild original "facts".
I only happened upon this thread this evening. The concept of dinosaurs cavorting in 3% carbon dioxide is mind-bogglingly WRONG!

 

[Jacob]

....... was over 3000ppm or 3%, the ideal levels for plants! and 750% higher than today.

So, when I hear about thermal runaway of the atmosphere, we are all doomed, it seems rather strange when the world not only survived but thrived with massively higher CO2 levels. Why doesn’t this ever feature when we talk about climate change?

It does feature (but not your maths!) You must have missed it!
https://news.climate.columbia.edu/2...-when-co2-was-extremely-high-why-cant-humans/

414.72 parts per million divided by 1 million multiplied by 100 gives the percentage 0.041472%

 

[Terry - Somerset]

Looking back at previous geological epochs does indeed show periods of incredibly vigorous life with CO2 (and O2) levels much higher than now. Of course the species alive now are not evolved or adapted to those conditions. But there’s also periods where life was rather more precarious; in the early Triassic for example most of the land was desert, and terrestrial life clung on round the coasts. In many cases the junction between the geological periods was a mass extinction event. That is very scary; we may well be heading that way now.

The most famous mass extinction event was the most recent; it happened at the end of the Cretaceous period when all the dinosaurs were wiped out (except birds). It wasn't the worst such event; about 67% of all species went extinct. But that’s not the full story, presumably over 99% of life was extinguished, but small numbers of 33% of species managed to hang on while the environment stabilised again.

So, if we are headed for an anthropogenic mass extinction, as current extinction rates suggest, it isn’t a question of whether we can live without badgers, it’s a question of whether we are one of the species that manage to scrape through. If we are, it’ll be a few thousand people here and there, and not 8 billion.

The capacity of most animals to materially adapt to a changing environment is very limited - sometimes lacking the capacity to adopt new foods where existing sources collapse, move to higher ground to avoid predators or water, find shelter if temperature changes etc.

Human beings are the exception. They have the capacity to survive (even thrive) in very diverse environments - artic to the tropics, wide open plains to mountains, deserts to rainforests etc.

I do not think it will be a case of only a few thousand survivors even with more extreme models of climate change. Of the 8bn around today, if only 5% survive there will be 400m left.

How comfortable or unpleasant the transition is will depend on timescales which could range from a few decades on a major tipping point to several millennia as ice melt and sea level rise has effect.

As the threat of climate change arises through the increasing exploitation of limited resources by a rapidly growing population, there is a certain "natural justice" in population reduction to a very much more sustainable level.

 

[Terry - Somerset]

Lush plant growth mean a more forest fires. Or new opportunities

Lush plant growth tends only to happen where there is a high level of rainfall. Areas at risk are where limited rainfall leaves plants and trees relatively dry.

 

[Croolis]

That carbon cycle pic above brings back memories (over 15 years ago now) . I've got one of my old year one textbooks here on the shelf "How Does Earth Work?". I wonder if anything in there is no longer valid (probably not).

Here's a fun thing to ponder: sea level rise is mostly caused not by melting ice, but by heat expansion. Antarctic and Greenland ice shelf collapse can alter that a good bit, but IIRC (and I cba to check) it's really mostly about heat expansion. That means that the water has been loaded with a carp ton of energy. We tend to think of sea level rise as, well, what it sounds like - water levels going up, maybe with the odd Hollywood style tsunami thrown in for some dramatic effect.

But in fluid dynamics (I was always garbage at fluid dynamics/mechanics/whatever it is, my maffs is not good), things behave differently when they are heated, of course. What happens when all those countless billions of litres of water are warmed, even if it's just by a degree or whatever? You might get higher waveforms, more peaky stuff, for example. Maybe just a centimetre or a few mm something, I have no idea, probably not enough to bother a mariner in the smallest boat (or maybe much worse). But on bigger scales, you'll probably suffer much higher levels of coastal erosion because of all that extra energy battering away.

Maybe the "zone of mixing", the spot where fresh water flowing from rivers into sea estuaries meets salt water, moves upriver some distance because of the extra force of tidal systems. The sea spray patterns, the fog banks, local weather, sandbanks, all the ecosystems local to all this, all this will irrevocably change. And then there's the inevitable feedback loops that all these changes make and could accelerate the initial change.

I have no idea how accurate any of these ramblings I'm doing here are, but what I'm getting at is - this is just one global phenomenom I'm talking about here, and the possibilities are myriad. And yes, this sort of thing goes on all the time naturally, it's all a big dynamic system. But we're the ones throwing up the energy traps. You don't need a Milankovic cycle to cook us up when we make our own version of the effect. Whatever the effect will be, there will be an effect. If you try to deny that, you're need to go have a rethink.