[A-AS04] 大気化学

[AAS04-16] メタン・対流圏オゾンの放射強制力の低減を目指して：アジアにおけるCH₄, NO_x, NMVOCの排出削減目標

*秋元 肇¹、永島 達也¹、谷本 浩志¹、Klomont Zig²、Markus Amann² (1.国立環境研究所、2.国際応用システム分析研究所)

キーワード：極端気象、短寿命気候汚染物質、アジア排出規制

In order to reduce impacts of climate change, including potential further increase of damages due to extreme events related to global warming, reduction of burdens of CH₄and tropospheric ozone in Asia are discussed. In order to mitigate the inevitable further increase of radiative forcing (RF) of ca. 0.8 W m^-2by 2040 caused by the increase of CO₂in 2040, feasible reduction of the industrial RF of methane (CH₄) and tropospheric ozone (trop-O₃) to the 50% of the values in 2011 are targeted to compensate 50% of the RF increase of CO₂. The remaining RF of CH₄and trop-O₃(0.26 and 0.22 W m^-2, respectively) correspond to the historical levels in 1960-1970. The necessary reductions of anthropogenic emissions of CH₄, NO_xand NMVOC in Asia in 2040 to the level of 1970 from that of 2010 have been estimated to be 35% CH₄, 44% NO₂, and 22% NMVOC from those of 2010 assuming the same necessary reduction ratio as for the global emissions. The estimated reductions have been compared with the reduction amount proposed in the Solution Report prepared under UN Environment Asia Pacific Office in 2018. The presumed reduction of the Asian emissions by 2030 through introducing of proven control measures are 27, 57 and 55% for CH₄, NO_xand NMVOC. Thus, the reduction of RF of more than 50% from the reference year of 2010 is feasible for trop-O₃if the emissions of NO_xand NMVOC from other part of the world could be reduced coherently. Further efforts would be necessary for the reduction RF of CH₄by more than 50% of the present value.