全球智库信息集成服务系统(G2TT): Impact of population growth and population ethics on climate change mitigation policy.

G2TT

来源类型	Article
规范类型	其他
DOI	10.1073/pnas.1618308114
	Impact of population growth and population ethics on climate change mitigation policy.
	Scovronick N; Budolfson MB; Dennig F; Fleurbaey M; Siebert A; Socolow RH; Spears D; Wagner F
发表日期	2017
出处	Proceedings of the National Academy of Sciences 114 (46): 12338-12343
出版年	2017
语种	英语
摘要	Future population growth is uncertain and matters for climate policy: higher growth entails more emissions and means more people will be vulnerable to climate-related impacts. We show that how future population is valued importantly determines mitigation decisions. Using the Dynamic Integrated Climate-Economy model, we explore two approaches to valuing population: a discounted version of total utilitarianism (TU), which considers total wellbeing and is standard in social cost of carbon dioxide (SCC) models, and of average utilitarianism (AU), which ignores population size and sums only each time period’s discounted average wellbeing. Under both approaches, as population increases the SCC increases, but optimal peak temperature decreases. The effect is larger under TU, because it responds to the fact that a larger population means climate change hurts more people: for example, in 2025, assuming the United Nations (UN)-high rather than UN-low population scenario entails an increase in the SCC of 85% under TU vs. 5% under AU. The difference in the SCC between the two population scenarios under TU is comparable to commonly debated decisions regarding time discounting. Additionally, we estimate the avoided mitigation costs implied by plausible reductions in population growth, finding that large near-term savings ($billions annually) occur under TU; savings under AU emerge in the more distant future. These savings are larger than spending shortfalls for human development policies that may lower fertility. Finally, we show that whether lowering population growth entails overall improvements in wellbeing—rather than merely cost savings—again depends on the ethical approach to valuing population.
主题	Air Quality & ; Greenhouse Gases (AIR) ; Mitigation of Air Pollution (MAG)
关键词	population, climate change, social cost of carbon, social welfare, emissions
URL	http://pure.iiasa.ac.at/id/eprint/14915/
来源智库	International Institute for Applied Systems Analysis (Austria)
引用统计
资源类型	智库出版物
条目标识符	http://119.78.100.153/handle/2XGU8XDN/130994
推荐引用方式 GB/T 7714	Scovronick N,Budolfson MB,Dennig F,et al. Impact of population growth and population ethics on climate change mitigation policy.. 2017.