Category: Science

Right now, the atmospheric concentration of carbon dioxide (CO2) is around 385 parts per million (ppm), up from about 280 ppm before the Industrial Revolution. Scientists, economists, and others disagree about what figure to accept as a ‘safe’ maximum concentration, with uncertainty enduring both about what temperature increase any particular concentration level will mean and what the social, political, physical, and biological consequences would follow.

Probably the most cautious group of all, with regards to what concentration is safe, is Bill McKibben’s 350.org, with their target of a reduction to 350 ppm. One major supporter is top NASA climatologist James Hansen:

If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm.”

By contrast, many environmental organizations have expressed support for targets between 450 ppm and 550 ppm, usually while hoping that such an increase would not generate more than 2°C of additional warming. Whether it would do so or not depends primarily on the relative strength of feedbacks within the climate system.

With extremely aggressive cuts in human greenhouse gas emissions, it could be possible to stabilize concentrations below their current levels. One major reason for this is the oceans. When CO2 is added to the atmosphere, it is akin to adding more CO2 to the area of air at the top of a soda bottle. Left alone, some of that extra CO2 will end up dissolved in the soda. In precisely the same way, if human beings were to stop emitting CO2 today, the levels would gradually begin to decline, until the amount of CO2 dissolving into the ocean became equal to the amount bubbling out of the oceans: a stable equilibrium with constant macroscopic properties. As such, the oceanic acidification that arises from climate change does, to some extent, reduce the amount of warming that would result from any set quantity of CO2 emissions.

Recentlly, Bill McKibben appeared on The Colbert Report, where he did quite a good job of getting his message across despite Colbert’s unique style of interview. (Link for those in Canada)

It has long been common knowledge that there is a general correlation between rising income in states and falling fertility. While women in very poor states give birth to an average of around eight children, those in the richest places can only expect to give birth 1.5 times on average. Because individual wealth is generally rising around the world, it has been assumed that this transition will help to stabilize the global population sometime this century.

Research by Mikko Myrskyla, at the University of Pennsylvania, suggests that things may not be so clear-cut. While rising income does correlate with lower fertility in states with a low grade in the Human Development Index (HDI), the trend seems to reverse when scores rise above about 0.9, out of a possible 1.0. Back in the 1970s, no state scored higher than 0.89. Now, more than two dozen do.

The research suggests that wealthy states with high HDI scores will not see their populations peak and begin to contract, but rather that they will stabilize and level off. This has a number of implications. Firstly, it could mean that the long-anticipated pension and health crises associated with having fewer workers per retiree might be less severe than expected. Secondly, it could affect immigration patterns and policies. Many people have been assuming that immigration would be the only way for rich states to maintain their populations. If this proves untrue, it could have a significant political, social, and economic impact. Thirdly, stable populations with rising wealth and very high rates of per capita resource and energy usage (and waste production) could spell special trouble for the climate and the environment generally.

When it comes to global population, it is difficult to know what sort of policies would promote environmental sustainability. As I suggested before, reproductive abstinence in the rich world does seem like a plausible way to reduce the total biophysical impact of humanity. It seems fair to say that the probability of any social and economic arrangement being compatible with environmental sustainability rises as the global population falls. A world with three billion people seems fundamentally less likely to experience environmental catastrophe than one with the same political and economic systems but a population of nine billion. Preventing an excessively high population from developing is thus a way of hedging against very bad outcomes, while making it more likely that there will be sufficient resources and waste-absorption capabilities for all those alive to live decently. If Myrskyla’s research is correct, one mechanism for achieving that aim that was previously considered all-but-automatic may in fact not be.

Giving testimony before a Congressional committee, former House Majority Leader Dick Armey argued that climate change cannot be a threat because god would not allow human beings to destroy the Earth:

Let me say I take it as an article of faith if the lord God almighty made the heavens and the Earth, and he made them to his satisfaction and it is quite pretentious of we little weaklings here on earth to think that we are going to destroy God’s creation.

By comparison, some religious individuals and organizations (including the Vatican and Archbishop of Canterbury) have argued that dealing with climate change is a religious duty.

Ignoring for the moment the question of whether any kind of supernatural beings exist, it does seem plausible to me that a fair number of people have a deep psychological assumption that something inherent to the universe would prevent the wholesale transformation of the Earth by human beings, at least if that transformation was a highly destructive one. For some, the balancing mechanism is a deity, for others ‘laws’ of technology or economics, and for others the (flawed) notion that natural systems are self-correcting. I recall a short story in which a man had the false belief that the fact that trains passing each other are drawn closer by the low pressure zone between them. He believed that the same phenomenon would help him stick to the train as he advanced up the outside of it. When it comes to environmental thinking, many people might be falsely comforted by similar misconceptions.

Dealing with climate change probably requires us to collectively appreciate that we have the power to totally unbalance the natural world, to an extent that our ecological niche could be threatened. Furthermore, we are actually actively doing so. As the proverb says, if we don’t change course, we might end up where we’re headed.

Incidentally, if there were an omnipotent, omniscient, benevolent god, it would be rather difficult to understand what it could have had in mind in setting up the relationship between fossil fuels, greenhouse gasses, and climate change. It’s a bit like leaving poisoned cupcakes out where your children will find them. Providing such a potent and easily accessible form of energy, but with dire long-term consequences that people took a while to figure out, seems like cruel game-playing. Of course, it is very hard to look at what happens in the world and believe that there is an omnipotent being out there looking out for us.

As mentioned before, the Swedish company Vattenfal has a carbon capture and storage (CCS) demonstration plant in Germany. The idea was to separate pure oxygen from air, burn coal in it, then ship the resulting carbon dioxide (CO2) to an injection facility 150 miles away by truck. The liquified CO2 was then to be injected 3,000 metres underground in a depleted gas field.

Now, due to local opposition, the CO2 is simply being vented into the atmosphere. The company has been unable to secure a permit to bury the carbon, so plans to begin doing to by March or April of this year have been scrapped.

It is hard not to be of two minds about this. On one hand, it is a justified blow against those who assume CCS will be a cheap and simple way to deal with climate change. There are big economic, safety, and effectiveness questions that need to be answered. At the same time, it will not be possible to answer those questions without the kind of demonstration plant Spremberg could be.

A world in which safe, effective, and affordable CCS technology exists is one where catastrophic and runaway climate change is less likely. This is true for both direct and indirect reasons. Directly, fossil-fuel fired plants with CCS would emit less than their non-CCS counterparts. Also, facilities that burned biomass and buried the carbon could actually be net-CO2-negative. Indirectly, making it possible to keep using fossil fuels a bit longer would lessen the level of opposition to the transition to a low carbon economy, particularly when it comes to poor, large, and rapidly developing states like India and China.

We will have to wait and see how other CCS pilot projects – in Europe and elsewhere – develop over the span of the next few years.