Here's how they handled the exposure vs. control group:
Mice in the CO2-exposed group were housed within a semi-sealed, custom-made 393-L exposure chamber... the exposure chamber was also fitted with two 80-mm fans that ran continuously... Mice in the control group were housed in the same type of cages in the same room, but not within the exposure chamber.
So the exposure group were in a semi-sealed chamber where other toxins might have accumulated, and were subjected to continuous fan noise. Whereas the control group were not in a chamber and were not subjected to fan noise.
I don't think one can draw any valid conclusions from this experiment. They should have put both groups in the same type of chamber, both with fans, but just not introduced CO2 into the chamber for the control group.
I don't really see how this hand-wavy dismissal invalidates anything about the study. Both groups of mice were in the same room, and while they would be exposed to somewhat different levels of noise due to relative distance to the fans, the difference would be negligible. Same for the toxin buildup, the very reason the fans were present was to circulate the air, which was constantly both monitored and regulated. This was a core part of the whole setup and the main focus of the study.
Unless you find it more likely that the small background noise difference had a starker effect on the lungs than the mixture of gases going through the lungs constantly, I don't really see how any of the criticisms hold.
The fans were to circulate air within the chamber (because they worried, I think incorrectly, that the CO2 might sink to the bottom). There was nothing to stop the smell of urine, and other volatiles, such as outgassing from plastics, from accumulating within the chamber.
There's no reason to think the difference in noise was negligible, and noise can have a big effect on things like stress levels, which can have wide-ranging health effects.
Plus, there may well have been other effects of the chamber, such as different light levels, which could also have unknown health effects.
It's absolutely fundamental for an experiment like this to try to match the exposure and control conditions as closely as possible, aside from the one variable you're looking at. They failed to do this, so their results are worthless.
> There was nothing to stop the smell of urine, and other volatiles, such as outgassing from plastics, from accumulating within the chamber.
The paper states that the substrate and changing schedule had been shown to keep ammonia to low levels.
> There's no reason to think the difference in noise was negligible...
Actually, there is. A good 80 mm fan can push more than 10 cubic feet per minute at less than 10 dBA. That's far quieter than a human whisper or rustling leaves. It's comparable to the sound of a pin dropping. If mice are adversely affected by that, I don't see how they could survive the wild.
> Plus, there may well have been other effects of the chamber, such as different light levels, which could also have unknown health effects.
The point of making the environment for the exposure and control groups be as near identical as possible is to equalize not only the factors you thought of, but also the factors you didn't think of.
It's the idea that there were no important differences between exposure and control groups, despite their obviously different living environments, that is "pure speculation".
Certainly possible, but it seems more likely that the control group would have been exposed to something harmful from the lab environment air versus the CO2 group that was getting medical air.
> And did they have a "good" fan, or a bad fan?
The cheapest 80mm fan I can find on newegg.com is a $3.49 Zalman[1] that is 20-23 dBA. That's comparable to the sound of rustling leaves and far less than the sound of a quiet whisper (30 dBA) or a babbling brook (40 dBA). Someone would have to go out of their way to find an 80mm fan that is so bad that it would be louder than a natural environment.
> The point of making the environment for the exposure and control groups be as near identical as possible is to equalize not only the factors you thought of, but also the factors you didn't think of.
I completely agree. I don't recall seeing a paper I couldn't poke holes in though. The fact that their methods were imperfect does not make the study worthless. They found a modest effect for the given methods. It suggests there may be merit to follow-on studies, which would likely use different methods. That's a useful result that has added new information.
It’s too late to edit my previous comments, but I should mention that I actually agree with your statements about not being able to draw valid conclusions and that they should have used the same kind of chamber; however, I believe the methods were reasonable enough to provide some value.
The point of control groups is, in effect, to not have to have the conversation we are having. It is incredibly glarring to have such uncontrolled differences between the two groups. I personally tend to believe the results are "correct" and "logical" and "expected", but this belief of mine is how confirmation bias works, hence I can not relly on this experiment exactly because of the reasons OP mentioned.
Please stop taking HN threads further into ideological flamewar, regardless of how wrong someone else is about something or you feel they are. It just makes things worse. We had to warn you about this just a few days ago: https://news.ycombinator.com/item?id=27692859. If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.
Whilst I might share your frustration, your comment didn't add anything to the debate. The absence of comments like yours (from either side) is one of the reasons I come to HN, and is the reason I downvoted you.
What does fan noise have to do with lung growth? What “toxins” are you predicting would accumulate? This comment seems insightful on the surface, but does not make much sense in the context of the experiment. I would say they used a valid control here. There are plenty of better reasons to be cautious on their conclusions.
Personally, upon skimming the paper, I found it curious that male mice never saw significant effects in these experiments whereas females were weakly significant for only a few of these. Sometimes opposite trends were observed between males and females. That could be due to the difference in sample size (30 female vs 23 male). It also might only be affecting female mice, which would be unexpected (for me). But the differences and effects are not strong, and I am not at all convinced.
I also don’t like that they separated males and females here because I would not expect there to be differences in lung development between the sexes (do we have different lungs? I am not a physiologist so I definitely could be wrong on this) and I try and avoid designs that require two-way ANOVA.
Anyway, no need to bash the cage design, which is misleading I think, when the data themselves are as weak as they are.
If I had to reduce that to some phrases I would say : the easiest way to do bad science is to lie to yourself, so to do good science you must foremost learn how not to do that. And avoiding avoidable difference in cohorts is one of the first step to stay honest.
Did you notice if they pre-registered the separate analyses of males and females? Flexibility in the analysis of data ("researcher degrees of freedom") is likely one of the major causes of the replication crisis. Gelman's paper is excellent in showing how these issues manifest without any intended malfeasance:
while generally agreeing the experiment setup is far from perfect, I can imagine a number of physical manifestations of constant stress exposure. Heck, animals and people die from it if strong/persistent enough.
If a person can turn their dark hair grey overnight by exposure to massive stress, other effects can be present too.
Let’s just assume for the moment that the experiment is actually invalid (due to poor control group).
Experiments that have good control groups don’t show spectacular results. Only those experiments that have spectacular results get publicized by the popular media. Therefore you are seeing a kind of bias particular more to the popular media than necessarily the scientific field.
Have career scientists been held accountable for the replication crisis? I know Hanlon's razor says not to, but at this point I can't help but think medical and social science have been more or less taken over to produce propaganda. Not too dissimilar to what the CIA did during the Cold War.
It really doesn't need to be that complicated. From what I can see (in Psychology) a combination of statistical illiteracy and motivated cognition is more than enough.
Even more troubling, they completely screwed up the analysis, making a mistake that even undergraduates know to avoid.
They measured 12 factors (as shown in table 1) across 4 treatment groups (male/female in two generations separately). That's 48 variables, so with the p<0.05 significance level they used, they would, on average, see 2.4 "statistically significant" results just by random chance.
If I'm counting correctly, they found 2 "statistically significant" results, exactly as expected by random chance.
In other words, their results are statistically indistinguishable from chance, exactly like the famous "jelly beans cause acne" thought experiment.
Yes, it’s not valid to reject a null hypothesis involving multiple tests without using a multiple testing correction. The simplest conservative approach would be to use a Bonferroni correction and check whether any of the M tests has a p-value below alpha/M. Clearly, these results are not that significant. The study suggests a couple potential effects. To credibly evaluate them, the study needs to be repeated with more mice and/or fewer tests along with appropriate statistical analysis.
> So the exposure group were in a semi-sealed chamber where other toxins might have accumulated, and were subjected to continuous fan noise. Whereas the control group were not in a chamber and were not subjected to fan noise.
It's fine to be critical of methodology, but if they are testing for lung function and tissue compliance, then I am struggling to find a reason for fan noise to be a lurking variable in this case.
Frequently, in experiments done before "double blind" and "control group" became the standard, we had results where something for which we were "struggling to find a reason" to be important, actually turned out to be important. In a properly done experiment we would not need to have a conversation in which lay people guess what else might have affected the results.
This is an interesting study, but I wouldn't yet draw any conclusions about the potential effect of a future atmosphere on human physiology based on the mouse model.
We shouldn't draw any conclusions because this study doesn't support any conclusions.
They measured 48 variables and found two were "statistically significant" at a p<0.05 significance level. But that's exactly what you'd expect to find purely by random chance if there's no real effect.
Would be relatively inexpensive to scrub CO2 in indoor spaces (in developed countries), with NaOH for instance [0]. (I wonder why this wouldn't already be a thing: normal indoor CO2 [1] is in the same range as the global CO2 in the OP mouse paper. Indoor air pollution is underappreciated).
[0] see https://en.wikipedia.org/wiki/Carbon_dioxide_scrubber (The amine methods wouldn't be a good idea, because the smell is reportedly extremely vile. It's what nuclear submarines' life support uses -- I forgot the link but there was interesting article about this).
You'd basically need to fit the entire food production capacity for each person inside a building to counteract the CO2 from breathing. Exhaled CO2 comes from food, so the same mass of carbon would have to be converted back into food or other plants.
Chemical scrubbing seems more viable, and might be a thing we start seeing in HVAC systems of the future.
More specifically, the CO2 has to get out of your blood to make way for the next load of oxygen, and that happens in your lungs not via your digestive tract.
He slightly mis-wrote, he meant percentage of carbon from food that gets converted to CO2 and then exhaled. Not all of food carbon becomes CO2 therefore you don’t need exactly equivalent biomass growth to offset food consumption.
Farts are not your breath. And if any significant fraction of the carbon in your stool converted into CO2 (which is odourless), released continuously would be bad enough (not as bad as breathing through your backside but much worse than any normal farting), and doing so all at once would be dangerously explosive — in the “you need emergency hospital treatment for a ruptured intestine” sense rather than a the slapstick comedy sense.
It's probably easier to concentrate oxygen/nitrogen and add them, rather than scrubbing CO2. It's a lot harder to remove a gas than it is to dilute it by adding other gases.
A home oxygen concentrator can be had for <$1k. The most difficult thing might be reliably monitoring the gas levels to make sure an unsafe imbalance isn't created.
Scrubbing CO2 is very easy because it is a pretty reactive chemical -- simply spraying air with a strong alkaline solution works. Separating nitrogen is by comparison very involved (it's a cryogenic distillation of liquefied air), and also there's like three orders of magnitude more of it.
Check the wikipedia article I linked: this is a solved problem in multiple contexts.
No? You use filtered outside air to mix it down to outside levels and only then add concentrated gas (cryogenically separated from the same outside air). It would probably be just a few pounds of oxygen (instead of a few pounds of scrubbing mixture that needs to be trucked in and out).
If you can just flood in outside air then you don't need any pure gas at all.
If need pure gas, for example you're trying to avoid losing your air conditioning or you're aiming for sub-ambient CO2, then you can't mix in lots of outside air. For the former you'd need enormous amounts of cooling and humidity adjustment, and for the latter outside air will actually make your job harder. So in those circumstances, the math is very simple. A human outputs X CO2, you want X to be a fraction of a thousandth of the air, you either scrub it or you add thousands of X in purified oxygen+nitrogen.
You seem to be assuming that the only physiologically-relevant factor is the ratio of O2 to CO2 in the air. I am pretty sure that is wrong: for example, dissolved CO2 makes the blood significantly more acidic whereas dissolved O2 does not make it more basic.
Also, the US Navy's submarine service, the Space Shuttle and the Apollo missions solved the problem by removing CO2, not by adding other gasses.
The amine smell isn't vile but it's strong and sticks in clothes and other fabric and most people probably don't want to deal with it if there's an alternative.
And that's at an industrial scale - residential scale would be even more expensive. Not all of the CO2 in the air has to be removed though and humans are not at home all the time.
It would cost, at the very highest range, $50t to stop climate change over 20 years. That's $2.5t per year, or $2,500 per middle class person for 20 years. Plus, we get a whole lot of benefits from a cleaner environment without oil and coal.
Its cheaper and more effective to just... deal with oil and coal usage as a collective, rather than all of these ad-hoc individual amelioration measures.
All of these schemes about CO2 capture don't make sense atmospherically (we're physically digging out too much carbon to put it back into the ground economically) -
But CO2 capture makes sense inside buildings.
Of course, all of this is just an extra burden on the individual - buying air filters, CO2 capture, expensive ventilation, CO2 monitors - when we could just restrict our coal and oil usage in the first place, much more economically.
This is junk science on so many levels it's laughable.
First of all, the population of large modern cities is already exposed to CO2 levels equal to or greater than the test level (900 ppm) nearly 24/7. I just took my CO2 meter and walked around the house. The levels range from 980 to 1165 ppm, the garage having the lowest levels.
Atypical? I don't think so. Not at all. I'll go measure my neighbor's homes and the office when I get a chance. It only stands to reason that a sealed environment would have higher CO2 levels. Modern buildings, in order to be energy efficient, are sealed-up fairly tightly. This makes both air conditioning and heating more efficient. Therefore, without constant air exchange program (which nobody does) CO2 levels indoors are going to be higher.
In fact, outdoor CO2 levels right now are 425 in my backyard and 613 in the front of the house. Measurements taken about 30 cm from the ground and away from any vegetation.
Are people dropping dead? NO
Are people ending-up in the hospital with horrible respiratory system problems? NO
If these numbers were statistically significant one would be able to point out equally significant pandemic-like respiratory and other issues across a massive portion of the population.
What's even more interesting is that 2020 caused everyone to lock down indoors FOR A WHOLE YEAR! This means billions of people were exposed to potentially higher CO2 concentrations than normal. The assumption here being that a more active population moves between indoor and outdoor environments, at least on a transitory basis while going to work, market, etc.
People are not dropping deal like flies at CO2 levels in the 1,000+ ppm range.
This also brought-up another question: We spend hours in our cars. What's the CO2 level in there?
I measured three vehicles, small, medium and large. I took measurements with the air conditioning system set to bring in outside air as well as recirculate (what you might do on the highway to avoid sucking-in fumes). The levels ranged from 680 ppm to 1264 ppm. Now I am interested in getting numbers while driving on the highway with a full load of people in the car. I'll get those numbers tomorrow.
Back to the junk science experiment.
First, as someone pointed out, the size of the test chamber was, objectively speaking, ridiculously small. 60 x 50 x 140 cm. Since it is somewhat difficult to visualize volumes sometimes, I went and measured a couple of household items to get a sense of proportion.
All measurements in cm
Refrigerator: 91 x 83 x 174 volume: 1314 liters
Dishwasher: 60 x 50 x 75 volume: 225 liters
The test chamber's internal volume was 420 liters.
Here's what's odd. They list the internal dimensions as 60 x 50 x 140, which is 420 liters. In the article they claim the internal volume was 393 liters. I'll assume they used-up 27 liters with equipment.
That being the case, the volume of air the mice had available to them was in the order of 1/3 of the volume of a refrigerator and 75% greater than that of a dishwasher.
AND THEY KEPT 53+ MICE IN THERE FOR ELEVEN WEEKS!
Go stand in front of your refrigerator right now and imagine 53 mice in that volume. Go do it. I'll wait...
What's the ratio of air available? 393/53 = 7.4 liters per mice
What's the ratio of air available per human, for a family of four, in, say, a typical 2000 square foot (186 square meter) home? 113,267 litters per person
What's the weight ratio between a mouse and a typical person? About 2,700 to 1
Scaling the air available per person, this would translate into a requirement of nearly 42 liters of air per mouse. The test chamber had SEVEN.
While my calculations are not meant to be precise, the idea is to get a sense of proportion here. If you wanted to conduct an experiment that truly simulated free space exposure to any given level of CO2 concentration you would have to have a chamber of a volume sufficient to eliminate the possibility of creating deficiencies as well as contaminating the very air you are relying on to test for exposure. I mean, what do 53 mice farting for 12 weeks do to a chamber 1/3 the volume of a refrigerator? Their control loop had a single variable, CO2 concentration. Nothing else triggered an any kind of an adjustment to the environment in that chamber.
I could go on, but I'll stop here. There's a whole segment of society --government, academics and zealots-- who are going way out of their way to attempt to create FUD powerful enough to scare people into doing things we should not be doing. Yes, yes, yes, climate change is real and we contributed greatly to atmospheric CO2 concentration. None of that is in doubt at all. This isn't about denying any of it. This is about suggesting we need to start having the right conversations and stop lying to each other.
It is probably fair to say hundreds of millions of people have been living a great deal of their lives in >1000 ppm CO2 levels inside of cars and buildings for decades, maybe 50 or 100 years. Maybe more. Last I checked, the sky hasn't fallen yet.
Of course, one might say: Well, when outside levels get to 900 ppm what will inside levels be?
This is interesting. The test was conducted at the predicted atmospheric CO2 levels in EIGHTY YEARS. In other words, not any time soon. For a sense of proportion, anyone born today will likely be dead by then. So, yeah, a while from now.
This exposes a level of dishonesty (or hubris, if I want to be kind) that is far too common for those wanting to push junk science: Reality is reduced to a single variable. In this case, for a whole 80 years nothing, absolutely nothing changes in the world and the one-and-only variable --atmospheric CO2 concentration-- climbs and climbs and climbs. Like I said, dishonest. I'll add ignorant and manipulative to that.
We know, without a shadow of a doubt, that the planet --because this IS a planetary scale issue-- reacts to CO2 concentration through changes in weather. In fact, we know, also without a doubt, that the two things that happen are: Lots of "water events" (rain, hurricanes, cyclones, etc.) and lots of vegetation growth (trees, forests, etc.). Do you know what indoor farmers add to their environment in order to promote rapid plant growth? CO2. Exactly.
And so, reality isn't a single variable problem. It's a complex multivariate machine. Will outdoor atmospheric CO2 concentration ever get to 900 ppm? Who knows? Nobody knows. And nobody can say one way or the other. What is far more likely to happen is that the planet will continue to react to increased availability of CO2 --as it has been for millions of years-- and possibly prevent this.
Of course, I think we can expect to have shifted almost entirely away from fossil fuel for ground transportation. I can see that being the case in, say, 25 years or so. In other words, anyone who bought a new car today and keeps it for, say, ten years, will likely have lots of good options by that time to buy an electric vehicle. I am doubling that and adding five years to my electric conversion estimate.
The scientific and technical communities need to start pushing for honesty in this field or we are going to waste valuable time and resources on things that will be utterly pointless for the future of humanity.
For now, plant lot of trees and stop cutting down forests. That seems like the most proactive and harmless things we can do without requiring massive government spending programs.
> This is junk science on so many levels it's laughable.
I disagree.
They make a very limited conclusion that 890 ppm CO2 appears to modestly impair the lung development of female mice.
They did not observe an adverse effect on either male mice or adult female mice.
They make no claims about people dropping dead or ending up in the hospital with horrible respiratory problems.
The chambers had circulating fans and a medical air supply that prevented the CO2 level from rising above 890 ppm. The substrate and changing schedule were consistent with practices shown to keep ammonia levels to negligible concentrations. Their methods appear reasonable.
Your inflammatory mouse flatulence speculation seems less scientific in comparison.
It reaches no useful conclusion after torturing 53+ mice (and likely killing them).
You seem to have missed the data I provided. Yes, single data points from my own environment, but it stands to reason that these numbers are likely not uncommon in modern urban environments, homes and offices included.
In fact, I went over to a couple of my neighbors homes and took similar measurements, indoor and out. Same range of numbers. Upstairs, downstairs, in the back, in the front, in their cars.
What does this tell me?
This "research" was pointless. People have been living in 600 to 1000+ ppm CO2 concentrations, likely for decades.
What's the point of torturing mice with an experiment that doesn't even provide a reasonable analog?
What's the point of killing mice in an experiment where the control loop is only driven by CO2 concentration and does not provide adequate free air to dissipate everything and anything else?
53 mice in a box 1/3 the volume of a refrigerator?
My problem with this kind of "science" is that bits and pieces of the conclusion will be make their way into both popular brainwashing marketing as well as documents used to justify governmental policy. Ten generations into the copy-paste train the fact that this was a less-than-ideal experiment devoid of useful conclusions will not matter. Politicians will say things like "Global warming causes a 125% inflammation of the lungs". A statement that has absolutely no support in the findings at all. And yet, it will be taken as a true statement and used to drive outrage, votes, policies, etc.
Won't happen? This wouldn't be the first time.
One of my favorites --which did not lead to policies but rather silly technology and spending-- is a paper from the 1970's that reached a conclusion related to photosynthesis using purple light (no green spectral content). This led to indoor farms and growers buying purple lights to grow plants. In the last couple of years everyone started to realize this was a bad idea and everyone is rapidly moving towards white light now.
Much as is the case with the mouse CO2 experiment, the purple light experiment has serious issues. However, everyone copy-pasted conclusions and charts to justify their decision to go purple. In reality, the experiment looked at something like ground-up plant leaf cells under conditions that have nothing whatsoever to do with real live plants being grown for food (or recreational products).
That's how "junk science" can lead to undesirable unintended consequences. And that's why it should be identified as early as possible. These conclusions are not useful. And, when it comes to climate change, we are wasting valuable time focusing on absolute nonsense.
The reason is simple: In the research community it is professional suicide to speak-up against what politicians and other interests want to drive. You get research dollars and are elevated to hero status if you provide fuel for their madness. And so, if you'd rather have a job and funding, you ignore reality and pander to the political forces pushing this nonsense. That's how we get to 53 mice in a small box and call this "research".
I must highlight (because my statements can be misconstrued) that this is NOT about denying climate change at all. It's very real and, yes, we accelerated CO2 concentration through our industrial expansion. No question about that at all. What isn't real is that (a) we can fix it ("save the planet", a convenient emotional pull for votes and support) and (b) that we are all going to drop like flies (we've been living in 1000+ ppm CO2, likely for 50 to 100+ years).
Anyone who disagrees with me should go out and buy a CO2 meter --as I did years ago. Then go around and measure the environments you've been living and working in for the last several years. From there, assess your own general health and, if compelled, have a doctor give you a full (and relevant) check-up. I'll bet you are going to be VERY surprised to discover you've been living in 600 to 1000+ ppm CO2 environments for a very long time and you and your family are OK.
After that, go around to friends and family and repeat your measurements. Once again, I think you'll be very surprised by what you discover.
If you don't do this, please keep your thoughts to yourself. You are not even operating with the most basic of data sets --data about your own environment-- to understand that some of these claims are just ridiculous.
1) Many people already live in high-CO2 indoor environments. Please see my earlier comment elsewhere in this thread where I relate how my own home quickly shoots up to over 1300 ppm if I turn off my ventilation system. Most people don’t even have ventilation systems.
2) People should monitor their indoor air quality. Consider giving a CO2 monitor to friends and family who don’t have one.
3) We can draw no conclusions from this paper. Please see my earlier comment that the statistical analysis is flawed and the methods could have been better.
4) There is a serious problem with the motivations, execution, dissemination, and interpretation of research today. This has been a problem for as long as scientific papers have existed. Einstein once told Norbert Weiner that he deplored the flooding of the literature by immature, idea-less papers. I don’t think the situation has improved since then. Recent politics haven’t helped.
5) Animals, even mice, should never be harmed without strong justification.
Here’s where we disagree:
1) The fact that people already live in high-CO2 environments does not imply there are no ill effects. There have been multiple studies indicating that high CO2 environments significantly degrade cognitive performance by large amounts. This implies some plausibility for developmental effects in children, which we have seen with other pollutants.
2) Although your outdoor CO2 measurements are not individually unusual, you should generally see an average below 500 ppm unless you live near an unusual outdoor source of CO2. Even next to a busy road in a highly polluted city, the average should be below 600 ppm. I suspect there is either an issue with your monitor or your breath may be sometimes drifting to the sensor. Your own breath can cause errors of several hundred ppm. Be sure to keep the sensor at arm’s length and stay downwind. Even better, get a unit that will record a history and step away from it for awhile.
3) You imply the paper makes extreme claims that it does not actually make. You are probably right that others will make extreme conclusions, but that is different.
4) A study does not need to reach a valid conclusion to have value. Much of science requires eliminating dead ends and finding potential hypothesis for follow-up. It is not economically feasible to study all possible hypothesis. We must make some advancements through incremental trial and error. This paper serves an exploratory function. The methods are reasonable enough to propose hypotheses for a couple of developmental effects. This was really more of a pilot study, although I doubt that was the intent. I’ve seen worse pilot studies that were still useful. To reach credible conclusions, other studies would need to be performed using a larger number of subjects and/or fewer tests along with better statistical analysis.
5) For the past 10,000 years, outdoor CO2 levels averaged around 280 ppm. Tripling that over a few hundred years is an extreme event. It is vital that we understand the potential consequences as soon as possible. I believe mitigations are possible if we develop sufficient motivation.
I don't think I made the claim that our living in high CO2 environments means there are no ill effects. Yes, we are not dropping like flies. I truly don't feel it is an emergency that justifies wrecking entire economies to "save the planet" and other great sounding fake objectives.
I absolutely agree this should be the focus of further research as well as an awareness campaign. Modern building design (homes in particular) are seriously deficient on this front.
With regards to my outdoor readings, well, this is sunny California. There's a highway about a mile away. Not sure to what degree this might skew readings.
While taking readings I was very careful not to breathe on the thing. In fact, this is one of the first things I tested. It is incredibly sensitive, doubling the reading by breathing on it from a couple of feet away isn't all that difficult.
As to your third point, I am not sure I am implying that they make extreme claims. In fact, the conclusion they reach is almost a letdowns in the sense that there was no horror associated with exposing these poor animals to a CO2 level that the planet might not see for a century --if ever. My concern is that a bad study on 53 mice crammed into a box not much larger than a portable ice chest will now start to get quoted by those driving politically motivated narratives as yet another "the sky is falling" fake data point.
A proper study would attempt to look at two or more populations living in very different environments. Humans, that is. For example, study groups of people in both urban and rural areas in different parts of the world. A software developer in Los Angeles or NYC is exposed to far higher levels of CO2 concentration than, say, a rancher in Montana or a tribe in the Amazon. This, if done carefully, could provide us with important data from which to both take action at the individual level and drive sensible policy.
(5) The accumulation of CO2 by humans in the last century or two is very easy to explain and understand. For this you have to go back to ice core atmospheric sample data that is good for at least 800K years of accurate history. The accumulation --which usually took somewhere in the order of 25K to 75K years-- was due to, well, continental scale forest fires. Remember, no humans to do anything about it. Fires were probably far more of a normal reality than we might think today.
The record clearly shows that at a delta increase of about 100 ppm things started to reverse. The 100 ppm decline from there took about 50K to 100K years. Once again, no humans to "save the planet"...it just happened.
How? Rain, hurricanes, cyclones, storms and the massive regrowth of vegetation. The big sequoia trees are 2000 to 3000 years old. The time scale we are talking about represents 25 to 50 times that lifetime. It's hard to imagine.
Sadly, this data leads to a very simple conclusion: We cannot "save the planet" or affect change. At all.
Why?
Because the baseline would be if all of humanity left the planet tomorrow and all of our technology shut down.
We know precisely how long it would take to affect a 100 ppm reduction in CO2 if this were to happen: It would take 50K to 100K years. We know because we have data dating back to before humanity was able to make an impact. In other words, to be crude, anyone selling a solution is selling complete bullshit. There is no way anything LESS than leaving the planet is going to improve the baseline rate of change had if we all left the planet --the most extreme "save the planet" move.
This is a harsh reality. Solar panels, wind power, electric cars, not using fossil fuels, etc. Nothing is going to materially affect the path we are on. Not in one human generation. Not in a thousand. Can't happen.
BTW, I know of at least one paper where this conclusion was reached [0]. Interesting read because the researchers actually set out to show the world how renewables were doing to "save the planet". I admire the fact that they came right out and effectively said "we were mistaken".
What do to, then?
Well, we definitely clean-up our act. There's no reason not to. We can create better living environments. We just have to do it because this would be of benefit for other reasons (the cognitive issues you mentioned) within a reasonable human time scale.
Plant trees and stop mass deforestation. Not so simple, but this is something we can do proactively that will help. No, it will not stop CO2 accumulation in a human time scale. Yes, it should improve local conditions in this scale if done correctly.
What we should NOT do is anything in a list of hairbrained ideas being pushed for political or financial gain. From seeding beaches with chemicals to building city-scale scrubbers and killing entire economies by waging war against fossil fuels. These things range from pointless to dangerous. We are far more likely to kill all life on earth by pretending we can manage planetary scale problems than to do any good.
Going back to the kind of research I said could help. The question is very simple: If billions of us have been living in 1000+ ppm environments for perhaps a century or more (think buildings in the 1900's or earlier, no central air, etc.), is this our "normal"? If humanity has been doing well under these conditions, the doomsday scenarios being painted are likely false as can be.
Sure, there might be issues with these living conditions. And yet, this is how we have lived for a very long time. From the school teacher to the researchers who gave us the COVID vaccines, everyone is likely living and working in 1000+ ppm environments. I am not suggesting this is acceptable. I just don't know. What I do know, to repeat myself, is that, despite what we are being told, the sky doesn't seem to be falling.
These higher CO2 levels (890ppm) are already a problem indoors. Ventilation systems become less effective as outdoor CO2 levels increase. Many houses and apartments around the world have no ventilation systems at all.
Its... mind boggling, or collectively insane, that we are doing so little. We risk stupefying ourselves into inaction since CO2 also has negative cognitive impacts.
For starters we need to shut down all coal plants and thermal coal mines (physically occupy them if necessary), cease manufacturing new ICE vehicles, and tariff any countries that don't impose carbon prices.
I highly recommend that everyone reading this buy an air quality monitor (CO2 + Pm2.5) so that you can at least monitor your own indoor CO2 levels.
I agree. Many people essentially live in sealed boxes that only receive ventilation through cracks and the occasionally opened door or window. My home averages around 800 ppm and that is with a fresh air ventilation system that is constantly running to exchange the air. If I turn off the ventilation system, I measure CO2 levels over 1300 ppm within a matter of hours. CO2 levels above 950 ppm are associated with significant impairments to cognitive function.[1]
Not sure why this was downvoted: it's an entirely correct [0] and a very relevant take on the OP study. If you're drawing inferences on future human health impacts from the OP, you should be drawing similar inferences about indoor air pollution, today.
> For starters we need to shut down all coal plants and thermal coal mines (physically occupy them if necessary), cease manufacturing new ICE vehicles, and tariff any countries that don't impose carbon prices.
Fortunately we already have a cheaper alternative to coal, and are making the factories to deploy this solution as fast as we can.
This is especially important given we need to reduce global emissions by at least 99% and keep it that low for the next thousand years or so.
If we didn’t have better cheaper options, you simply wouldn’t be able to convince enough foreign governments to shut down their plants and mines with any level of tariffs at all (look at North Korea or Cuba for the effectiveness of the harshest trade restrictions the USA can pursue), never mind sustaining that economic pressure for the millennium-long atmospheric lifetime of CO2, and even doing so unilaterally would just make you poorer and industry relocate.
Good thing PV and batteries are cheaper than coal or gasoline, and are still getting cheaper. The combination should be cheaper than natural gas in a few years, PV by itself already is.
I don't know. I'm imagining a parallel dimension where coal is cheaper and solar is growing exponentially at 20% per year. And someone is using that exponential growth to argue they're making solar panels factories "as fast as they can" even though they're completely wrong.
Is there anything you can buy to reduce indoor CO2 levels without exchanging outdoor air? Is bubbling air through a tank of algae the only solution available to consumers? I'd love some product recommendations from HN, if anyone has one.
Air exchange is the most economical solution. You can’t stuff enough plants in a typical home to make a measurable difference and there are other pollutants such as VOCs that air exchange will address. Here are the two least expensive options I know of:
1) Get a CO2 monitor and partially open a couple windows whenever the level is above 800 ppm. Cost: $60.
2) Get a good air filter such as an IQAir HealthPro+ and pair it with a ducting adapter such as https://www2.iqair.com/sites/default/files/documents/InFlowW.... This will allow you to constantly exchange your indoor air with filtered fresh air. If you don’t want to install a wall intake for the duct, you can connect it to a window adapter like what is used for portable A/C units. Cost: $1,500.
Ive been very happy with this one. Bought it mainly for fire season out here in California but seems good for monitoring the collapse of human civilization too.
It doesn’t track co2. You can have 0 pm2.5 and still be in a stuffy room with too much carbon dioxide (which is quite common in Poland in Winter for example. Air cleaners remove pm2.5, people keep windows shut to keep pollution and cold air from getting in, and they get crazy amounts of co2 indoors).
Just talking about CO2 has negative cognitive impacts, as this thread demonstrates. People will apply any stretch of the mind they can to avoid having to face the problem.
The remarkable collective insanity is that we can't be sane collectively. It takes only a minority to make collective action impossible and individual action pointless.
So you can buy an air monitor but all it's going to do is affirm that the inevitable is actually happening.
I don't think what you describe as 'insanity' is at all confined to climate change though. It actually seems weird to me to be surprised that we find it hard to take collective action on this.
We're talking about a (in relation to a human lifetime) gradual process, with costs relatively far in the future. Experimental evidence shows all sorts of costs are exponentially discounted over time — so why should this be any different, for people taking individual actions or deciding whether to elect pro-environmental governments? Other problems are just more pressing: what to feed your kids without them whining about vegetarian food; how to pay the rent; how to get promoted if this requires long distance travel; enjoying time with friends and family if they live at a distance.
Most people, in most places, at least acknowledge the issue. It doesn't mean they're jumping up to pay the costs, but it's an ordinary discussion about responsibility and economics rather than an assault on science.
The delusions are largely limited to one country, for whom this is not merely about the difficulty of collective action but a paranoid belief that it's a massive global hoax. That's a whole new level of delusion.
If people aren’t going to combat climate change on the bases of mass extinction and threat to all advanced civilization as we know it, I don’t expect they will be persuaded by ill health effects.
I wouldn't count on that necessarily. Mass extinction and threat to all advanced civilization seems abstract, your own ill health seems more personal. https://en.wikipedia.org/wiki/Framing_(social_sciences) You often see news stories with a personal frame to drive them home, rather than a situational frame.
Though I don't know, indeed, you might have it right, it might make no difference.
Hundreds of millions ignore the obesity impact on their health. And that’s something you can feel right away. I seriously doubt people are going to pay attention to something so intangible.
I doubt they ignore it. People that are obese and fine with it are a minority. That doesn't mean it's easy to stop being obese. Compared to obesity, CO2 doesn't have genetic factors, the science on it is clear, there are easy solutions to monitor it. You could also do something like make people do a test in a CO2-heavy room and in a CO2-light room. On the other hand, you can't show obese people what it's like to not be obese, or non obese people what it's like to be. The two situations are very different.
False. It’s not that hard to fool yourself into thinking that you will be able to navigate the societal disruption that will be caused by climate change, especially if you have money. If you have the resources you can move north, pay more for food, hide behind the security services. But no one wants to imagine living inside a literal bubble or seeing their grandkids crippled by CO2 poisoning. Escaping the heat and its effects is one thing—it’s entirely a different thing to have to escape the atmosphere.
Water pollution like this is a localized phenomenon. The concentration of CO2 in the atmosphere is not. What the study is saying is that there may be no environmentally safe outdoor spaces anywhere in the world at the end of the century. This has never been the case previously, even when environmental pollution has gotten out of control in certain places.
It’s not about it being local(which I bet it’s not anyway). The point is that we can witness an example of people literally drinking mud. And they still continue polluting what’s left of the water.
I thought the same thing then I saw how people freaked out over COVID and it gave me some hope. I thought masks would never catch on as much as they did. So perhaps there’s room for manipulating people into effective action if we can find the right triggers.
I frequently try to express this to people and I don't know how to get it across sometimes. Our representative republic has been so clogged up by corporate interests that we can't even pass infrastructure that would benefit most of those same corporate interests at this point. I have basically zero faith that we will be able to address climate change in any meaningful way.
'Advanced civilization' is the reason the human animal is deeply sick; if we saw any other animal population with 15% requiring psychiatric medication, [1], 40% obese [2], with fertility rates plummeting below replacement rate [3], we would conclude that this animal species was deeply distressed and experiencing a social collapse reminiscent of those observed in Calhoun's rat utopias. [4] But because we evolved a highly capable rationalization mechanism, people are able to convince themselves that things are OK even as various trends worsen. (A common justification is 'we're not animals, we can ignore out instincts - meanwhile, everything we do is driven by instinct.)
Even from an environmental perspective, sure, burning fossil fuels isn't sustainable and has disastrous ecological impacts. I agree. So does battery production, microchip production, industrialized farming, etc. We are polluting and destroying the ecosphere with all of our 'advanced' civilization, not just climate change. The air and water are filled with all kinds of man-made poisons, not just fossil fuels, and we're inventing more every day.
This is not a problem that can be solved with more technology.
That's why I don't worry too much about climate change. If it gives us a systemic collapse sooner rather than an even worse one later, that's a good thing. More people will survive at a higher level of culture. I don't see anything upsetting about this. People thrived most of the time for most of human history prior to the Industrial Revolution.
> For starters we need to shut down all coal plants and thermal coal mines (physically occupy them if necessary)
So are you personally enlisting in the marines or somewhere else? Also, who’s gonna pay for green energy for a billion Asians? Since it’s them who’s adding most new coal plants.
It’s easy to say “occupy if necessary” sitting on a couch. It’s ridiculous how people throw words like this. And statistically speaking, the majority of commentators here never even held an assault rifle in their lives.
Mice in the CO2-exposed group were housed within a semi-sealed, custom-made 393-L exposure chamber... the exposure chamber was also fitted with two 80-mm fans that ran continuously... Mice in the control group were housed in the same type of cages in the same room, but not within the exposure chamber.
So the exposure group were in a semi-sealed chamber where other toxins might have accumulated, and were subjected to continuous fan noise. Whereas the control group were not in a chamber and were not subjected to fan noise.
I don't think one can draw any valid conclusions from this experiment. They should have put both groups in the same type of chamber, both with fans, but just not introduced CO2 into the chamber for the control group.