Development of a new index of global waming potential for short-lived replacement compounds for CFCs

2014 Fiscal Year Final Research Report

• Project/Area Number: 22241009
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental impact assessment/Environmental policy
• Research Institution: The University of Tokyo
• Principal Investigator: Ryoichi Imasu 東京大学, 大気海洋研究所, 教授 (40334255)
• Co-Investigator(Kenkyū-buntansha): 齋藤 尚子 千葉大学, 環境リモートセンシング研究センター, 助教 (50391107) ; 田村 正則 独立行政法人産業技術総合研究所, 環境化学技術研究部門, 主任研究員 (40357489) ; 陳 亮 独立行政法人産業技術総合研究所, 環境化学技術研究部門, 主任研究員 (70371060)
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 代替フロン / 放射強制力 / 地球温暖化係数 / 環境技術 / 気候変動 / 気象 / GWP

Outline of Final Research Achievements

Most acceptable candidates as replacement compounds for chlorofluorocarbons (CFCs) are hydorofluoroethers (HFEs) and hydrofluoroolefins (HFOs). The rate constants of reaction of these chemical species with OH radical were determined by laboratory experiments. Based on these constants, atmospheric lifetimes of the compounds were estimated, and global warming potentials (GWPs) were updated. On the other hand, chemical transport model based on a global circulation model (GCM) have been developed to calculate the global distribution and radiative forcing of these replacement compounds in the atmosphere. After achieving a stable state in concentration of the compounds in interest, globally integrated radiative forcing can be evaluated. We propose, as a conclusion, to use these values as a new measure to represent more reliable climate impacts of replacement compounds which have shorter lifetimes in the atmosphere.

Free Research Field

大気物理学

Academic Significance and Societal Importance of the Research Achievements

IPCCの第4次報告書において報告されたヒドロフルオロカーボン(HFC)の代替物質であるヒドロフルオロエーテル(HFE)やヒドロフルオロオレフィン(HFO)などの物質の地球温暖化暖化ポテンシャル(GWP)値について、より信頼度の高い値を提示することができる。これにより、実際に使用するHFEを選択する判断基準がより明確になることで、HFCからHFEへの転換を促すことに繋げられる。