Warm for a 1000 Years

Stabilization of Carbon Dioxide (1)

In January of 2009 Susan Solomon and colleagues published a paper called Irreversible climate change due to carbon dioxide emissions. The article appeared in the Proceedings of the National Academy of Sciences. This paper focused specifically on carbon dioxide in the atmosphere and made the argument that the effects of man-made carbon dioxide on the climate would last more than 1000 years – their definition of irreversibility.

The lifetime of carbon dioxide in the climate system, specifically in the atmosphere is more difficult to calculate than for many greenhouse gases. This is because of the role of the oceans and the terrestrial ecosystems. A balance develops between the terrestrial carbon dioxide, the carbon dioxide in the ocean and in the atmosphere. While one can find citations that the lifetime of carbon dioxide in the atmosphere is on the order of 100 years, Solomon and her co-authors point out that when one considers how long today’s “excess” carbon dioxide from industry influences the climate, it is in excess of 1000 years. It for this reason that if we stopped burning fossil fuels immediately, that the Earth’s surface would continue to warm and remain warm.

( Roger Pielke, Sr. wrote a piece, Narrow Thinking In A New PNAS Paper “”Irreversible Climate Change Due To Carbon Dioxide Emissions” By Solomon Et Al 2009 challenging not the science-basis analysis of Solomon’s paper, but stating that it exaggerated the role of carbon dioxide relative to other causes of climate change. Solomon’s paper is quite clear that it is focusing on carbon dioxide.)


The Solomon paper highlights the fact that the decisions we make today with regard to carbon dioxide emissions will be consequential for the future. That is, what we do in the short term matters a lot to the stabilization of atmospheric carbon dioxide. Stabilization is the word that is used to mean limiting the amount of carbon dioxide to some specified value. The Solomon paper affirms that we must be anticipating and preparing for adaptation to global warming and sea level rise. They also note the likely intensification of the dry season in dry parts of the world.


Another paper that I find useful is by Bryan Mignone and his co-authors. The paper is Atmospheric stabilization and the timing of carbon mitigation . The paper appeared in 2008 in Climatic Change . This paper evaluates the difference between starting a 1% per year reduction of carbon dioxide emissions versus continuing our greater than 2% per year increase. If we started this reduction then we could stabilize the concentration of carbon dioxide at about 475 parts per million (ppm) , which can be compared with current values, about 390 ppm, and the pre-industrial value of about 280 ppm. Every year we delay, we commit to an extra 9 ppm.

One of the goals of limiting carbon dioxide in the atmosphere is to avoid “dangerous climate change.” Often numbers such as 450 and 550 ppm have been posed as the maximum amount that is allowed. Jim Hansen has been arguing that we are already in the realm of dangerous climate change and that we need to target a stabilization amount of 350 ppm. His arguments are made on an examination of past climates, and calculations of the amount of warming that can tolerated to stabilize ice sheets, sea ice, alpine glaciers, and ocean acidification. ( see here as well)


Barring sustained economic retraction, which we fight with all of our might, carbon dioxide will continue to increase for many years. Even though several countries and states have announced plans to have measurable reductions by 2020, and politicians talk about 50 – 80% reductions by 2050, the path to that reduction is not obvious. Technological development and deployment of new technology is needed. Not only is it required to develop alternative energy sources enhance efficiency, but it is necessary to develop sinks of carbon dioxide. Every time I walk through this problem, no matter by which path, I come to the conclusion that we will be required to not only sequester carbon dioxide, but also to develop the technology to remove carbon dioxide from the atmosphere. We cannot rely upon the ecosystems and the oceans; it’s too much carbon dioxide.


Next blog will focus on modeling studies that show the impact that different stabilization strategies might have on the climate.

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Ye Olde Stabilization Blog: A Strange Urgency




Figure 1: Stabilization of Atmospheric Carbon Dioxide as a Function of Emissions (from IPCC).