An Assessment of Global Macroeconomic Impacts Caused by Sea Level Rise Using the Framework of Shared Socioeconomic Pathways and Representative Concentration Pathways

Osamu Nishiura,Yasuaki Hijioka,Junya Takakura,Kiyoshi Takahashi,Shinichiro Fujimori,Makoto Tamura

doi:10.3390/su12093737

Abstract

Coastal areas provide important services and functions for social and economic activities. Damage due to sea level rise (SLR) is one of the serious problems anticipated and caused by climate change. In this study, we assess the global economic impact of inundation due to SLR by using a computable general equilibrium (CGE) model that incorporates detailed coastal damage information. The scenario analysis considers multiple general circulation models, socioeconomic assumptions, and stringency of climate change mitigation measures. We found that the global household consumption loss proportion will be 0.045%, with a range of 0.027−0.066%, in 2100. Socioeconomic assumptions cause a difference in the loss proportion of up to 0.035% without greenhouse gas (GHG) emissions mitigation, the so-called baseline scenarios. The range of the loss proportion among GHG emission scenarios is smaller than the differences among the socioeconomic assumptions. We also observed large regional variations and, in particular, the consumption losses in low-income countries are, relatively speaking, larger than those in high-income countries. These results indicate that, even if we succeed in stabilizing the global mean temperature increase below 2 °C, economic losses caused by SLR will inevitably happen to some extent, which may imply that keeping the global mean temperature increase below 1.5 °C would be worthwhile to consider.

Highlights

IntroductionAt the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change, the Paris agreement was adopted as a new framework from 2020, when the second commitment period of the Kyoto Protocol ends [1]
In recent years, climate change has become a great concern worldwide
We compare the results among scenarios and compare them to the inundation impacts introduced to the computable general equilibrium (CGE) model

Summary

Introduction

At the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change, the Paris agreement was adopted as a new framework from 2020, when the second commitment period of the Kyoto Protocol ends [1]. The Paris agreement aimed to mitigate climate change and to adapt to its adverse impacts. In the Paris agreement, the importance of support for developing countries that are especially vulnerable to climate change is emphasized [2]. Low-lying coastal areas are among the main places threatened by exposure to climate change. Because of the geographical and socioeconomic conditions in particular low-income countries, the damage caused by SLR is considered a major threat among climate change impacts, and one that can harm their economic growth. An economic assessment of SLR and adaptation measures for it would be meaningful for policymakers

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