nate_meurer

That's a good point, and good examples. I'd compare the destruction of aquifers (some of them anyway) as akin to those things.

> Water which is evaporated is also returned to the ecosystem. It falls back out as rain.

This is about as useful as saying "the water stays on Earth". The ecological damage entirely depends on the nature of the water source.

The most poignant situation is non-rechargeable aquifers. When water is extracted, the mineral structures collapse and the storage capacity is forever destroyed.

And as the other reply stated, evaporation (as from evaporative cooling) exports water out of a catchment basin so that it can't be used downstream, just as if you pumped it away.

This looks like a good review, and it definitely pertains to your effort here. Although the authors play up the positivity of their conclusions a bit (which is useful if they want to continue the research), they are also honest about the limitations of the material they cite. Many positive correlations are cited, but nearly every paragraph is laden with caveats. Here are a few pulled at random:

> However, the relationship between CO2 concentrations and upper respiratory symptoms in this study was no longer statistically significant after adjusting for the number of people in the office

> A 100 ppm increase in CO2 concentration (range, 549–1318 ppm) was positively correlated with non-specific symptoms including headache and dizziness (107 participants from 11 offices) although the correlation was not significant

> Several epidemiological studies indicate a relationship between low-level exposure to CO2 and BRSs. However, BRS is possibly influenced by other comorbid indoor pollutants, including artificial volatile organic compounds (VOCs) brought into buildings or occupant-generated pollutant

> CO2 concentration at 5000 ppm had no effect on acute health symptoms (respiratory, visual and skin-related, headache, and sensory) and performance in cognitive tests (Zhang et al., 2016).

> the relationship between low-level exposure to CO2 and the reported symptoms remain inconsistent between studies

> A relationship between low-level exposure to CO2 and BRSs is therefore very complicated to prove and strength of the evidence is very limited.

My biggest issue with all of this is that we have a ton of data from very high-CO2 environments going back decades, and still very little clear evidence of negative effects. If high CO2 concentration imposes significant cognitive costs for which the human body cannot compensate after some period of time, it seems like that signal should have become clear by now.

No, I pointed out specific flaws in those papers. You're just pretending that I'm dismissing them out of hand so you don't have to read them yourself.

Once again, the Australian study that's the source of your original assertion was very small (n=4 in each study group) and very short term (only a few hours of study time). And the paper about bicarbonate levels is a great example of data dredging, where coincident trends are implied to be causative with no further support.

I'm not saying the conclusions are wrong. They could both be right. I'm just saying that their methods are too poor to draw any useful conclusions.

> people who can't cope or perform in the high CO2 environment quit or fail

So here you are dismissing evidence out of hand by pretending not to understand it. Even if submariners are selected based on CO2 tolerance (which is silly), it wouldn't matter. The point is that the US Navy has had a large population to study for long periods of time in highly controlled environments. The same men can be examined before, during, and after exposure to very high concentrations of CO2, while other environmental variables are held constant, and the navies of multiple countries have data from many such populations over decades. That's what produces useful data, in contrast to that tiny, short Australian study you seem to be attached to.

It's an interesting article overall, but this assertion:

> Carbon dioxide is bad for cognition.

is dubious and unsupported by science. As I point out downthread, we have extensive experience with very high-CO2 environments-- at levels regularly exceeding ten or twenty times current atmospheric levels-- and as yet little good evidence of uncompensated cognitive effects.

Beyond that, modern humans live much of our lives in moderately elevated CO2 with no apparent ill effect. Without deliberate ventilation, any enclosed space like a bedroom or classroom will rapidly achieve elevated CO2 levels, often into the thousand ppm range. Again, we have lots of data, and little of it points to a practical cognitive effect.

The US Navy maintain an informal goal to keep levels on board submarines to below 8000 ppm, loosely informed by what little evidence they have of its effects on crew performance. That's twenty times the current atmospheric levels. In practice, CO2 levels often go over 10,000 ppm, which apparently still doesn't cause them much concern.

> Cognitive decline starts above 600 ppm according to air quality studies.

According to an older, small study of short duration (Mendell and Fisk at LBNL), the results of which are heavily disputed. Since 600 ppm isn't too much higher than the current level of 400+ ppm, this study is the one most commonly cherry-picked in order to instill fear in people that climate change is getting ready to damage our brains.

Just for comparison, the CO2 composition of exhaled breath is around 40,000 ppm (~4%), which is the reason that it's totally normal for CO2 concentrations in enclosed spaces like bedrooms and classrooms to reach several thousand ppm. CO2 levels in submarines average well over ten times atmospheric, and routinely reach well over 10,000 ppm.

In none of these situations have researchers found a clear and convincing long-term impact on cognitive performance. Short term yes, but our bodies and brains adapt. Some compensations appear incomplete, but others are possibly sufficient to incur health benefits from high CO2 concentrations. Notably, high CO2 levels cause blood vessels to dilate, increasing the flow of oxygen to tissues including the brain. There is in fact ongoing research into medical therapies using concentrated CO2.

Interest and military and take a distant third and fourth place respectively. Here are the rough proportions of the top US federal budget expenditures according to the Treasury Department:

- Healthcare (Medicare and Medicaid): 24%

- Social Security: 23%

- Net Interest on Federal Debt: 15%

- National Defense: 13%

And I'll point out that the enormous bill for the interest on debt is a pretty good reason to avoid ringing up so much debt in the first place.

Well yeah, it's still debt. It's still the unpaid balance of the cost of goods and services.

The essential purpose of a market for IOUs is to allow us to issue a lot more IOUs. This is critical to the industrial and technological development that has allowed us to stop living in the dirt. But liquid debt markets can also be weapons of mass destruction by allowing misallocation to compound into ruinous financial crises. Sort of like, oh I don't know, bloated, inefficient government entitlement programs funded by massive debt that can only be dealt with by a.) confiscating the labor and assets of the population by force, or b.) monetizing the debt and inflating it away, which is itself a backdoor tax on the same population.

My point is not that economic surpluses don't ever exist, but that the perceived surpluses that people invoke in order to defend the present welfare state are unsustainable, and that the system will inevitably collapse without a miraculous increase in economic productivity. Debt (both private and sovereign) is literally the thing that tells us whether a society is able to pay for the things it demands. That's not an accounting trick any more than plain arithmetic is.

Food and clothing are actually an argument against you here. Sure we waste a lot of both, and yet food insecurity is rare in the First World, and lack of clothing is pretty much the least significant part of poverty. Plus, government-forced redistribution reliably increases prices overall due to the increased costs of logistics and administration. There is no free lunch.

If you want to argue your point, you have to address the real fiscal burdens on modern societies, and the real drivers of debt across the West. The biggest components of government debt are medical care and pensions (including Social Security in the US). These are the things that are bankrupting us, not food and clothing.

Norway's fiscal discipline is certainly the exception that proves the rule. Britain's failure to steward the wealth of its half of the North Sea's bounty provides a good example of that rule.

If that's true, it's odd that so many social welfare programs across the western world are consuming an ever-growing share of GDP, incurring massive debt, and grinding toward insolvency and collapse. Exactly how much more of our money and labor do you want to take from us in order to continue this madness?