As global climate change intensifies, city-level carbon accounting has become increasingly important, as cities are significant sources of carbon emissions. This paper provides an overview of key steps and considerations in city-level carbon accounting methods, with a particular focus on the bottom-up approach that involves defining accounting boundaries, selecting accounting perspectives, identifying emission sources, collecting data, determining calculation methods, and performing calculations and uncertainty analyses. Additionally, the paper introduces the top-down method that uses macro-level data to estimate carbon emissions at the city level and briefly discusses emerging methods for city-level carbon accounting. The strengths and limitations of these approaches are examined. The paper also provides an overview of different databases used for carbon accounting and evaluates their appropriateness for estimating carbon emissions at the city level. It also analyzes key research topics in the literature related to urban carbon accounting. Common challenges in city-level carbon accounting are discussed, along with recommendations for future research in this field.
Citation: Lei Fan, Haoyu Guan. A comparative overview of city-level carbon accounting: Key processes and considerations[J]. AIMS Environmental Science, 2025, 12(3): 400-418. doi: 10.3934/environsci.2025018
As global climate change intensifies, city-level carbon accounting has become increasingly important, as cities are significant sources of carbon emissions. This paper provides an overview of key steps and considerations in city-level carbon accounting methods, with a particular focus on the bottom-up approach that involves defining accounting boundaries, selecting accounting perspectives, identifying emission sources, collecting data, determining calculation methods, and performing calculations and uncertainty analyses. Additionally, the paper introduces the top-down method that uses macro-level data to estimate carbon emissions at the city level and briefly discusses emerging methods for city-level carbon accounting. The strengths and limitations of these approaches are examined. The paper also provides an overview of different databases used for carbon accounting and evaluates their appropriateness for estimating carbon emissions at the city level. It also analyzes key research topics in the literature related to urban carbon accounting. Common challenges in city-level carbon accounting are discussed, along with recommendations for future research in this field.
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