Spatial consumption-based carbon footprint assessments - A review of recent developments in the field

Consumption-based carbon footprint (CBCF) assessments have become increasingly important in studying the drivers of climate change from a consumer perspective. A wide range of studies and approaches for CBCF have been presented, yet a systematic and interpretative synopsis of the literature is missing. We present a comprehensive review of more than 100 CBCF studies published in Scopus-indexed journals until 2019. We analyze the methodological and conceptual development of spatially related CBCFs and provide guidance for future research. While the recent emergence of several global multi-region input-output (MRIO) models has meant remarkable development in assessment accuracy, there is space for improvement in hybrid-modeling and increasing sectoral detail. Furthermore, it was recognized that studies published under the same CBCF label actually fall into two categories with different definitions and potentially significantly different outcomes. We suggest labeling these as Areal CF (ACF) and Personal CF (PCF) in the future. ACF encompasses the CBCF of economic activities within selected geographic boundaries, and the global production and delivery chain emissions of the goods and services consumed therein, including those consumed by visitors. PCF covers the consumption of the residents of the area regardless of where the consumption takes place but excludes the consumption of visitors within the area in question. ACF analyses typically include government consumption and investments, whereas PCF analyses normally exclude these. This scope issue is seldom brought up in individual studies, and it currently takes a lot of effort and expertise to classify existing studies, which hinders their usability for policy-making. In addition, we suggest that future studies position themselves among previous studies on the same location, discuss potential reasons for differences in the results, and consider these when drawing policy conclusions.