If keeping below 450 ppm is said to be improbable – since the Copenhagen treaty talks so far have shown little if any progress – is 350 just a dream?
No. It is still possible. But we must act now. According to James Hansen and many others such as Lester Brown and his Plan B, we need to work on the things we can now, not prescribe some reduction scenario to take place – hopefully – over the next 20 or 30 or even 50 or 100 years.
Hansen is blunt.“The most important thing is to have a moratorium on new coal fired power plants that don't capture CO2 and then to phase out the dirty coal use over the next 2-3 decades.”
The argument is that all things being equal, the Earth will continue to absorb CO2, and CO2 would only go up to a bit more than 400 if we phase out coal use. But then we have to take at least 50 ppm out of the atmosphere, and that is possible with improved agricultural and forestry practices.
It is important to point out that the various goals for 2050 are not a sufficient way to look at the solution. A good fraction of the carbon dioxide that is put in the atmosphere from burning fossil fuels will stay in the air for a very long time, about a fifth of this stays in there for about a thousand years. We need to recognize the size of the reservoirs of oil, gas and coal. Coal is by far the largest of these. It is also the one which is conceivable to stop. It's very difficult to see how we can prevent the oil from being used and the carbon getting in to the atmosphere because it comes from vehicles. In the case of coal, if it is to be used, it could be restricted to power-plants that can capture and store the CO2. That becomes a practical way to look at reducing emissions and for many it's a better way than saying lets reduce it 80% or 90% or 60% or any particular number because we really can't let 40% or 20% of the coal to continue to be used.
The critique of the coal moratorium approach is that phasing out coal is economically and politically unworkable or impractical or flat out impossible.
To be sure, 50% of power generation in the US is coal. China is booming and opens a new coal plant every 10 days. Without coal Germany becomes beholden to Russian natural gas. Our integrated global economy, it is said, cannot affordably move away from coal.
Carbon capture and sequestration deep underground is promoted as the solution. In isolated cases this may be practicable. But this technology is still seen as being 10-12 years away from realization – 10 years that we don’t have. Further, it has not been shown to be cost-effective at this point. Finally, the sheer scale of the task: to sequester just 10% of the current CO2 production would require the equivalent of all pipelines currently in use by oil – an investment of trillions of dollars to handle 100% of the task.
However, in the United States, the tide has perhaps turned. The Carbon Principles announced by the three largest US banking institutions – Morgan Stanley, JP Morgan Chase and CitiBank – all but closed out loans for new coal plants that cannot demonstrate how they will meet foreseeable new regulations concerning emissions. This business decision was followed by prominent energy leaders and investors to change course. Warren Buffet, T. Boone Pickens and even Google have launched nearly a half trillion dollars of investments in clean renewable energy to replace coal – at a lower cost. In addition more than 60 new coal plants have been stopped.
By phasing out coal and moving away from fossil fuels to clean renewable energy sources, greater efficiencies in urban and building design, clean mobility solutions and with the help of reforestation and improved agricultural practices, the target level of no more than 350 ppm is still feasible, but just barely – time has run out for procrastination.
By any and all measure, the task now for civilization is Herculean. It must begin now.