Suburbs and climate change: a home-grown brawl

Cox goes on to hint at the most critical point, one that the Griffith trio conveniently dodge. The argument that correlation isn’t causality cuts both ways. If it isn’t valid to argue for causality in the direction of distance from the core, detached housing, more car use and lower population density to lower emissions, it’s just as invalid to do so in the opposite direction of proximity to the core, multi-unit housing, less car use and higher population density to lower emissions.

Green activists and planning dons are waging a campaign to impose their compact city vision on the rest of us, despite homebuyer preferences and the interests of a vital economic sector. Surely they’re obliged to prove their case. After the ACF atlas, Cox’s analysis and the failure to turn up usable evidence, that’s a challenge. The Griffith trio acknowledge this problem, but add “we read it differently”. The difference, though, is just a resort to obfuscation: “[i]n our opinion, current empirical evidence suggests influences on household greenhouse emissions and energy demands are complex and context dependent …”

Moving on, the Griffith boys fire a secondary shot at Cox’s method. While he treats household GHG emissions as a single factor (or variable), the “built environment” affects emissions from each set of household activities (travel, housing, recreation, food, clothing and so on) in different ways. Without specific research, however, they can’t show how Cox’s findings should have been otherwise. Their discussion amounts to little more than supposition.

Let’s finish where we started. Why was the ACF so blasé about the spatial dimension of its findings? Because GHG emissions are a function of overall consumption. Consumption shaped by low-density housing, whether it concerns transport, energy or infrastructure, doesn’t figure prominently in the composition of aggregate consumption. According to the atlas, it’s swamped by the profusion of consumption patterns across the urban landscape. This leads to a conclusion the ACF won’t like: if the object is to cut GHG emissions, singling out low-density suburbia represents a poor ordering of priorities.