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by clairity 1149 days ago
> "although the effects of CO2 in cognition and energy levels are debatable"

it's really not debatable. the feeling of stuffiness is a function of many things, but environmentally, it's mostly temperature and humidity (we humans are hot and breathe out lots of humidity). there are no cognitive/energy effects until you get into the 10's of thousand of ppm, as the mechanism of action is competing out oxygen, not some intrinsic maladaption to CO₂, which is actually vital to life on earth. it's fashionable to hate on carbon right now (it's mediopolitical), and that's really all there is to it.

particulates, VOCs and chemical off-gassing, on the other hand, do have known mechanisms of harm, and that's something you should be more concerned about, but not yet alarmed. most of that pollution comes from cars and coal/gas power generation, so long-term, we should move toward more efficient habitation (e.g., denser cities, public transit) and cleaner power generation (including nuclear) if we really care about our collective health.

practically no one should be worried about CO₂ in their daily lives. it's thoroughly a red herring.

2 comments

Yes they are debatable. There are cognitive performance tests that show statistically significant decline in many tasks above 1500ppm, especially on planning tasks. That's independently of the feeling of "stuffiness".

If these measurable declines have a sufficient impact on our lives and productivity is the debatable part.

Edit: here's one reference: "We also found effects of CO2 (a proxy for ventilation) on cognitive function. For every 500ppm increase, we saw response times 1.4-1.8% slower, and 2.1-2.4% lower throughput"

https://www.hsph.harvard.edu/healthybuildings/2021/09/09/imp...

if you look at the paper, you see no such conclusive evidence, but rather weak correlative assertions in noisy and complex environments. also notice the incentives and implicit bias of the involved. unbiased studies from the past several decades have so far shown cognitive effects require 10× that level of CO₂ to show any conclusive effects. even the pm2.5 effects attempt to make a short-term correlation, which is dubious at best. long-term pm2.5 effects are more conclusive, which is why we should be more concerned about them.

CO₂ is a fashionable concern but not scientifically supported. more importantly, it distracts from things we really should be concerned about as states and nations, like actual pollution and the alarming concentration of power and wealth.

See, they are debatable after all - we are debating them. There is data, there are some correlations that are statistically significant, and some raise even more questions — like why performance lowers at 1200ppm, but goes back up at higher concentrations in this article published on Nature in a very controlled environment - https://www.nature.com/articles/s41526-019-0071-6

I don't think this topic distracts from anything. I live in Finland, where indoor air quality is a big topic (mycotoxins and spores due to mold in old houses, burning wood in residential areas due to particulate emissions on cold days, construction codes, etc), while the country is making strides to become carbon neutral, and has one of the lowest economical inequality in the world.

But anyway, as I mentioned in the initial comment, the high CO2 just raised my attention to the bad ventilation of the house, and that includes ventilation of particulates from activities like cooking.

the CO₂ levels we see day-to-day (as long as you don't work in certain very specific industries) cannot have the effects that are fashionable to discuss. it's bullshit, an intentional disconcern for truth. bullshit by definition is distracting, as it literally takes attention away from truth-seeking and effective policy-making.
Do you have any sources on this? I'm keen to know more, but googling results in either very dry researchpapers or ads on either co2 meters or air purifiers.
here's a USDA fact sheet summarizing the effects of CO₂ at different concentrations that's more easily digestible than an academic paper: https://www.fsis.usda.gov/sites/default/files/media_file/202...
There are a number of studies that have found that CO2 levels lower than the OSHA limit of 5,000 ppm can still cause issues like slight cognitive impairment and worse sleep (however there's also a few studies that have found no or minimal impact of levels below 5,000ppm)