Pnas 114 (46) (2017)

Authors
Marc Fleurbaey
Princeton University
Mark Budolfson
Rutgers University - New Brunswick
Abstract
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.
Keywords population  climate change  social cost of carbon  social welfare  emissions
Categories (categorize this paper)
Options
Edit this record
Mark as duplicate
Export citation
Find it on Scholar
Request removal from index
Revision history

Download options

PhilArchive copy


Upload a copy of this paper     Check publisher's policy     Papers currently archived: 70,079
External links

Setup an account with your affiliations in order to access resources via your University's proxy server
Configure custom proxy (use this if your affiliation does not provide a proxy)
Through your library

References found in this work BETA

Weighing Lives.John Broome - 2004 - Oxford University Press.

Add more references

Citations of this work BETA

Fossil Fuels.Kian Mintz-Woo - forthcoming - In Benjamin Hale, Andrew Light & Lydia A. Lawhon (eds.), Routledge Companion to Environmental Ethics. New York: Routledge. pp. 317-326.
Can Parfit’s Appeal to Incommensurabilities Block the Continuum Argument for the Repugnant Conclusion?Wlodek Rabinowicz - 2019 - In Paul Bowman & Katharina Berndt Rasmussen (eds.), Studies on Climate Ethics and Future Generations, Vol. 1. Institute for Futures Studies.

View all 6 citations / Add more citations

Similar books and articles

Climate Ethics and Population Policy.Philip Cafaro - 2012 - WIREs Climate Change 3 (1):45–61.
Climate Change and Optimum Population.Hilary Greaves - 2019 - The Monist 102 (1):42-65.
El demonio de la superpoblación.Ludi Simpson - 2012 - Astrolabio: Nueva Época 8.
Climate Change, Intergenerational Equity and the Social Discount Rate.Simon Caney - 2014 - Politics, Philosophy and Economics 13 (4):320-342.

Analytics

Added to PP index
2020-05-20

Total views
27 ( #422,998 of 2,506,032 )

Recent downloads (6 months)
9 ( #81,150 of 2,506,032 )

How can I increase my downloads?

Downloads

My notes