Urban–rural disparities in household carbon footprints in Colombo, Sri Lanka
摘要
Households are major contributors to greenhouse gas emissions; however, spatial disparities in household carbon footprints (CFPs) remain underexplored in low- and middle-income countries (LMICs). This study presents the first comprehensive comparison of household CFPs between urban and rural settings in Sri Lanka. A community-based cross-sectional survey was conducted among 1569 households in the Colombo District using stratified multi-stage cluster sampling. Households with at least two adults and one child under 18 years were included. Data on household energy use, food and beverage consumption, travel, goods and services, and housing (including waste generation and water use) were collected using a validated tool adapted for Sri Lankan households and verified against utility records. Urban households (n = 1205) reported significantly higher mean CFPs than rural households (3515.6 vs. 2766.8 kgCO₂e; p = 0.001). Energy use was the largest contributor to CFPs in urban areas (mean = 1049.7 kgCO₂e), whereas travel dominated in rural households (mean = 834.7 kgCO₂e). Within these domains, urban households generated significantly higher emissions from electricity use (747.6 vs. 371.1 kgCO₂e), waste disposal (456.4 vs. 227.4 kgCO₂e), water consumption (51.3 vs. 26.9 kgCO₂e), and milk intake (276.4 vs. 164.8 kg CO₂e) compared to rural households. On a per-capita basis, emissions were 27% higher in urban than in rural areas (1010.1 vs. 794.9 kg CO₂e; p = 0.003). These findings highlight the importance of addressing behavioural diversity between urban and rural populations in climate mitigation. Urban policies should prioritize household energy efficiency, sustainable consumption, and improved waste management, whereas rural strategies should focus on expanding access to clean cooking fuels and low-emission transport options. By providing evidence from a South Asian LMIC, this study adds to the limited global literature on household-level emission disparities and informs the design of equitable, context-specific climate mitigation strategies.