【論文発表】世界的なコンクリート生産拡大とその砂・気候危機への影響

著者

Takuma Watari, Zhi Cao, André Cabrera Serrenho, and Jonathan Cullen

掲載誌

iScience, 2023, 26, 5, 106782, Link

要旨

Concrete production poses multiple sustainability challenges, including resource over-exploitation and climate change. Here we show that growing global demand for buildings and infrastructure over the past three decades has quadrupled concrete production, reaching ∼26 Gt/year in 2020. As a result, annual requirements for virgin concrete aggregates (∼20 Gt/year) exceeded the extraction of all fossil fuels (∼15 Gt/year), exacerbating sand scarcity, ecosystem destruction, and social conflict. We also show that despite industry efforts to reduce CO2 emissions by ∼20% per unit of production, mainly through clinker substitution and improved thermal efficiency, increased production has outweighed these gains. Consequently, concrete-related CO2 emissions have tripled between 1990 and 2020, and its contribution to global emissions has risen from 5% to 9%. We propose that the policy agenda should focus more on limiting production growth by changing how concrete structures are designed, constructed, used, and disposed of to address the sand and climate crises.