Global industrialization and urbanization processes enabled a diverse cement production boom over the past three decades, as cement is the most important building construction material. Consequently, the cement industry is the second-largest industrial CO2 emitter (∼25% of global industrial CO2 emissions) globally.
The past three decades have witnessed a soaring emission increase by 1.9 times of the global cement industry (0.86–2.46 Gt), but the emission patterns varied considerably worldwide and were significantly shaped by the surging emissions from the emerging countries.
Consistent with previous studies, a typical lifetime of 40 years is assumed for all units regardless of differences in country, kiln type, and operating year.
The Asian countries showed an emission increase by 5.3 times during 1990–2019 and emitted 70.3% (1.73 Gt) of the total CO2 emissions from the cement industry in 2019 compared to only 32.1% (0.28 Gt) in 1990, which is consistent with their increased cement production. The dramatical growth of this region was represented and led by the development of China and India. With rapid urbanization and industrialization, China’s CO2 emissions from the cement industry increased by 7.2 times (7.5%/year) from 0.15 to 1.24 Gt during 1990–2019, accounting for 50.3% of global emissions in 2019. However, the emissions from China have remained stable since 2014 following the peak cement demand, reflecting the demand saturation associated with socioeconomic development.
CO2 emissions in India also increased considerably by 4.4 times (6.0%/year) and climbed to 0.22 Gt in 2019 but have not reached a zenith. Considering India’s growing economy and large population, the CO2 emissions are expected to keep increasing with infrastructure expansion in the near future.
Similar to China and India, the other countries in Asia showed an emission increase by 2.3 times during 1990–2019 and contributed 11.2% (0.27 Gt) of the total CO2 emissions in 2019.
Due to their large emissions and rapid growth, the Asian countries should be the ones most targeted for future emission mitigation.
The Middle East and Africa contributed to 10.4% of the total CO2 emissions in 2019, and the emissions climbed 2.6 times in the past 30 years, reflecting the great potential as a future emission hotspot.
In contrast with the emerging countries mentioned above, the OECD and EU showed steady emissions (−0.3% growth rates per year) during 1990–2019, contributing to 14.6% of total CO2 emissions as of 2019.