Energy and Resources Group, ‡Goldman School of Public Policy, and §Department of Nuclear Engineering, University of California , Berkeley, California 94720, United States.
Environ Sci Technol. 2014 Jan 21;48(2):895-902. doi: 10.1021/es4034364. Epub 2014 Jan 2.
Which municipalities and locations within the United States contribute the most to household greenhouse gas emissions, and what is the effect of population density and suburbanization on emissions? Using national household surveys, we developed econometric models of demand for energy, transportation, food, goods, and services that were used to derive average household carbon footprints (HCF) for U.S. zip codes, cities, counties, and metropolitan areas. We find consistently lower HCF in urban core cities (∼ 40 tCO2e) and higher carbon footprints in outlying suburbs (∼ 50 tCO2e), with a range from ∼ 25 to >80 tCO2e in the 50 largest metropolitan areas. Population density exhibits a weak but positive correlation with HCF until a density threshold is met, after which range, mean, and standard deviation of HCF decline. While population density contributes to relatively low HCF in the central cities of large metropolitan areas, the more extensive suburbanization in these regions contributes to an overall net increase in HCF compared to smaller metropolitan areas. Suburbs alone account for ∼ 50% of total U.S. HCF. Differences in the size, composition, and location of household carbon footprints suggest the need for tailoring of greenhouse gas mitigation efforts to different populations.
美国哪些城市和地区的家庭温室气体排放量最大，人口密度和郊区化对排放量有什么影响？我们利用全国性家庭调查，建立了能源、交通、食品、商品和服务需求的计量经济学模型，用于推导出美国邮政编码、城市、县和大都市区的家庭平均碳足迹（HCF）。我们发现城市核心区的 HCF 始终较低（约 40 吨二氧化碳当量），而远郊的碳足迹较高（约 50 吨二氧化碳当量），在 50 个最大的大都市区范围内，HCF 的范围从 25 到>80 吨二氧化碳当量不等。人口密度与 HCF 呈弱正相关，但在达到密度阈值后，HCF 的范围、平均值和标准差下降。虽然人口密度导致大都市区中心城市的 HCF 相对较低，但这些地区更为广泛的郊区化导致与较小的大都市区相比，HCF 总量净增加。仅郊区就占美国 HCF 的约 50%。家庭碳足迹的大小、组成和位置的差异表明，需要针对不同人群调整温室气体减排工作。
