Friday, February 15, 2013

Why we need to regulate global carbon dioxide emissions

The level of vitriol in the public sphere (as far as climate change goes) seems to getting worse recently.
I normally try to stay out of the climate debate because it's extremely complicated and I think that it's important to not be alarmist. Alarmist (to me) means either advocating for an immediate return to 300 ppm levels of CO2 in the atmosphere (which would likely have drastically negative effects on economy...and ultimately on life in general) or it means advocating for the status quo because CO2 taxes would somehow destroy the economy. The economy will not tank if we implement a market-based CO2 tax that kicks in slowly over the next 20-50 years (and that doesn't lead to higher levels of government waste/spending.)

So, the question of course is: why should we regulate CO2 emissions? The answer that most people discuss is "The Climate." Some of the more extreme climate alarmists link CO2 emissions to specific hurricanes, storms, and droughts. They often ignore any benefits of a warmer climate, and then proceed to attack anybody who isn't 110% behind their cause. This is not the way of scientific discourse, let alone discourse in general. So, I figured that I'd write an article that trying to focus on known facts.

CO2 is a known greenhouse gas. There's no debate here. The question is: what is the effect of CO2 on the climate? The answer is that it's an extremely complicated effect. It depends on the amount of water vapor in the atmosphere, along with a lot of other positive and negative feedback mechanisms. Both the weather, the climate, and the economy are extremely complicated, and extremely non-linear. This means there is no solution to the question: what is the "optimal" amount of CO2 in the atmosphere? But before we throw up our hands, let's also look at the other aspects of CO2.

CO2 is required for photosynthesis. (But even those people working in greenhouses typically don't allow the CO2 levels to exceed 1000-1500 ppm. Too much CO2 is not good for least for the type of plants that have evolved to live in an environment of 300 ppm of CO2.)

CO2 is a known acid gas, though a really weak acid gas compared with NOx and SOx. But it is still an acid gas, and it is this quality to CO2 which makes it different than other gases in the atmosphere, such as N2. Higher levels of COwill slowly cause the oceans to be less basic (i.e. lower the pH) and will increase the concentration of dissolved CO2 species in the ocean. The effect of changing pH is complicated because it's not just a change in's also a change in CO2 concentrations and possibly temperature.

CO2 is also a toxic gas a quantities above 5000 ppm for humans (and likely for other animals.) OSHA and NIOSH (as well as the equivalent safety organizations in other countries) regulate indoor air quality and air quality in confined spaces so that workers aren't exposed to CO2 levels above 5000 ppm (8-hr time-weighted averaged.) See the following sites.
According to these sites, CO2 levels between 1000 and 2000 ppm can lead to drowsiness  Levels between 2000  and 5000 can lead to headaches, sleepiness, and loss of attention. At concentrations above 5000 ppm, this can lead to nausea.

Given that many of us work in buildings, it's important to make sure that CO2 concentrations don't go above 1000 ppm. If the concentration of CO2 in the atmosphere increases from 400 ppm to ~800 ppm due to continued emissions of CO2 from fossil fuel power plants and vehicles, then it will be a lot more difficult to keep the concentration of CO2 in building below 1000 ppm. It won't be impossible to do this. I'm just pointing out the fact that, regardless of CO2 's effect on global temperatures, we will eventually want to regulate CO2 emissions so that we all don't start falling asleep and complaining of headaches/nausea. There is more than enough fossil fuels in the ground to cause the CO2 levels to go above 1000 ppm. It would be nice to hope that plants and photosynthesis micro-organisms could keep the CO2 levels below 800 or 1000 ppm, but this does seem like a risky bet.

So, in conclusion, I'd like to see more discussion on the health effects of CO2 emissions, and less on "CO2 emissions caused this storm." As somebody who works in the area of non-linear dynamics, I recognize that  there is a slippery slope to lawlessness if we start blaming tropical storms on CO2 emissions. We might as well blame butterflies in the Amazon on Hurricane Sandy. The reason that I'm writing this post is that I'd like to see people focus on those aspects of CO2 emissions which have no possible benefits (and only negatives, such as sleepiness, headaches and nausea) and which are not highly non-linear. Personally speaking, I think that more people would understand the need to regulate CO2 emissions if you tell them that higher CO2 levels will cause sleepiness, headaches, and nausea than if you tell them that it will be warmer outside. Unless of course you happen to be talking to somebody who skis, snowboards, lives in the desert, or lives on the coast...then I suggest sticking to the global warming argument.  :-)

p.s. And as should be pretty clear from his website, we can still have a growing society, even after we regulate global CO2 emissions. We just need to switch to power plants with CO2 capture/storage (along with some renewables), and we'll need to switch to vehicles that don't rely on fossil fuels. This could be battery-electric vehicles, fuel cells, or cars running on renewable-derived liquid fuels. This transition needs to happen over the next ~50 years in order to keep CO2  levels at or below ~600 ppm. But it's got to be a global transition. We can continue to grow while keeping CO2  levels below ~600 ppm. But it will require global regulation of CO2 emissions or else we'll run into the age-old "Problem of the Commons."