Introduction

Rearranging urban spatial parameters, such as land-use mix and transportation, could reduce CO2 emission because urban form influences the volume of CO2 generated by households. This influence is felt in part through the design and density of residential buildings, which foster different energy consumption behaviour. Another part relates to lower transport energy use (Moriarty, 2002; Troy, Holloway, Pullen, & Bunker, 2003). The reduction could be more significant as the transportation sector alone contributes to a quarter of greenhouse gas (GHG) emissions in some cities (Stead, 1999). Despite the general recognition that land-use change can influence the use of certain transportation modes (Ewing & Cervero, 2001), and that the reduction of travel and modal split are relevant to GHG emission control (Department of Infrastructure, 2001), two major questions remain to be answered: (1) How do urban spatial parameters affect household CO2 emissions?; and (2) What urban planning policies can be introduced to change these parameters?