Revisiting the urbanization-emissions nexus: Heterogeneous effects and urban growth thresholds in sub-Saharan Africa

The purpose of this study is to analyse the distributional effects of urban population growth on climate change in sub-Saharan African (SSA) countries over the period 2000 - 2024. Given the high heterogeneity in emission levels and urban growth patterns across SSA, we employ Fixed-Effect Quantile Regression (FE-QR) to uncover distribution-specific effects that average models (OLS) may obscure. The ensuing outcomes are as follows: (i) urban population growth has a positive net effect on CO 2 emissions based on the OLS estimate; (ii) urban population has a negative net effect on CO 2 emissions at the 10th, 25th, and 50th quantiles. Furthermore, there is an avoidable urban growth threshold of 8.52%, 8.42% and 8.88% at the 10th, 25th and 50th quantiles, respectively in order to minimise CO 2 emissions in SSA countries. Policy inferences are presented. This study expands existing literature by revisiting how urban population growth influences climate change using quantile regression as an innovative technique within the context of a climate-vulnerable region.