A development of reduction scenarios of the short-lived climate pollutants (SLCPs) for mitigating global warming and environmental problems

Teruyuki Nakajima,Kei Yoshimura,Shingo Watanabe,J Kurokawa ,Gakuji Kurata,Toshihiko Takemura,Toshimasa Ohara,Yuji Masutomi,Kayo Ueda,Haruo Tsuruta,T Mäki ,Yongqiang Yu ,Makiko Nakata,Daisuke Goto,Tatsuya Hanaoka,Kentaroh Suzuki,Syuichi Itahashi,Kengo Sudo,Chieko Suzuki,Xerxes Seposo,Tomoko Nitta,Keiya Yumimoto,Toshihiko Masui,Shuyun Zhao

doi:10.1186/s40645-020-00351-1

Abstract

This study presents the results of the ERTDF S-12 project for searching an optimum reduction scenario of the short-lived climate pollutants (SLCPs) to simultaneously mitigate the global warming and environmental problems. The study utilized REAS emission inventory, Asia-Pacific Integrated Model-Enduse (AIM/Enduse), MIROC6 climate model, NICAM non-hydrostatic atmospheric model, and models for estimating environmental damages to health, agriculture, and flood risks. Results of various scenario search indicate that it is difficult to attain simultaneous reduction of global warming and environmental damages, unless a significant reduction of CO2 is combined with carefully designed SLCP reductions for CH4, SO2, black carbon (BC), NOx, CO, and VOCs. In this scenario design, it is important to take into account the impact of small BC reduction to the surface air temperature and complex atmospheric chemical interactions such as negative feedback between CH4 and NOx reduction. We identified two scenarios, i.e., B2a and B1c scenarios which combine the 2D-scenario with SLCP mitigation measures using End-of-Pipe (EoP) and new mitigation technologies, as promising to simultaneously mitigate the temperature rise by about 0.33 °C by 2050 and air pollution in most of the globe for reducing damages in health, agriculture, and flood risk. In Asia and other heavy air pollution areas, health-care measures have to be enhanced in order to suppress the mortality increase due to high temperature in hot spot areas caused by a significant cut of particulate matter. For this situation, the B1b scenario is better to reduce hot spot areas and high-temperature damage to the public health.

Highlights

The concept of the short-lived climate pollutants (SLCPs) has been created in the development of global warming mitigation policies to identify anthropogenic atmospheric compositions that produce positive radiative forcing
According to the IPCC special report on global warming of 1.5 °C (IPCC 2018), these global warming mitigation goals require a significant reduction of long-lived greenhouse gases (LLGHGs) emission at a level of almost zero by 2050, which demands the maximum effort of the society
This paper summarizes the key results of the S-12 project that aimed at searching an optimum mitigation path of Shortlived climate pollutants (SLCP) reduction, conducted in Japanese fiscal years of 2014–2018, through four research theme activities, i.e., (1) analysis of air quality change and development of emission inventories, (2) selection of mitigation technologies and scenario development, (3) investigation of SLCP impacts on the climate and environment, and (4) development for shared tools and a high-resolution atmospheric modeling to link a large variety of scales from regional to global

Summary

Introduction

The concept of the short-lived climate pollutants (SLCPs) has been created in the development of global warming mitigation policies to identify anthropogenic atmospheric compositions that produce positive radiative forcing.

Results

Conclusion