CO2 zero emission as the key concept of ICEF
ICEF started in 2014 and I served ICEF as the chairman of its steering committee. ICEF held its first forum in October 2014 and its second in October 2015. ICEF 2014 gathered audience of around 800, and ICEF 2015 gathered more than 1,000 from all over the world. In this sense these forums were successful. However after the two forums I felt that the focal point of the meetings was not so clear and discussions in the forums were distributed in broad areas, particularly in case of their plenary sessions. Therefore it is I felt indispensable at the beginning of the third ICEF forum to stress the importance of setting the goal we should reach by the future efforts for mitigating global warming and I did it at the third forum held in October 2016. The goal introduced at that time is “zero net anthropogenic emission of CO2”.
Then why I introduced this goal to ICEF? You may recall Article 4 of Paris agreement ratified in November 2016 which stressed the need to achieve a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century. The main differences between the goal being proposed in this paper and the above Paris agreement lies firstly in replacing greenhouse gases by CO2 and secondly in omitting the time limit we should achieve the goal.
Why did I make such difference in the proposed goal? The reasons are as follows.
1) CO2 is actually most influential among greenhouse gases to the rise in global mean surface temperature (GMST). IPCC AR5 WG3 assessment report(1) tells that the past trends and simulation results of global climate models show anthropogenic emission of CO2 are approximately linearly related to the rise in GMST . In other words in order to achieve stabilization of GMST zero anthropogenic emission of CO2 is required.
(IPCC report did not take anthropogenic absorption of CO2 into account, which was almost nothing in the past. If, however, we take absorption of CO2 into account we add the word “net” at the top of emission.)
2) Most greenhouse gases have shorter life time in the air than CO2 (For example the lifetime of CH4 is 12 years while that of CO2 is more than several thousand years).
3) The stabilization of GMST is the basic condition we should achieve in future. To limit the rise in GMST to some degrees and by some specific year are additional conditions.
4) We will develop innovative measures to mitigate climate change but development of some measures may take time to put into practice. Nuclear fusion and space solar power systems are typical examples. For the long term future we should develop such measures even if it takes time, as these technologies are almost resource free non carbon technologies. Stabilization of GMST is, regardless of when and at what level, to be realized eventually.
It is however not an easy task to realize net zero anthropogenic emission of CO2. Together with development of innovative technologies we should revise the structure of our social and economic systems for this purpose. I earnestly hope that ICEF will be the ground for discussions toward such total system innovations.
1. Climate Change 2013, The physical science basis, IPCC-SPM, p.27