The City of Cape Town’s Carbon Footprint - why the numbers matter

Well, it depends. There is, as yet, no standard methodology for calculating the carbon footprint of cities (although such methods are under development). Research led by Christopher Kennedy at the University of Toronto and published in Environmental Science and Technology in 2009 was one of the first attempts to develop a methodology and make comparisons between global cities. The work was motivated by the increasing recognition of the role of cities in reducing greenhouse gas emissions.

 

Developing a universal methodology is not straightforward. Firstly, there is the issue of what to include and what to exclude. How do we define city boundaries? Do we just consider fuel use and electricity consumption within the City’s municipal area? Or do we also take into account the carbon embodied in the goods that we consume and the food we eat? Tourism is key to the City’s prosperity, but should we then include the carbon emissions from all the flights made by visitors to get here?

 

Besides these methodological conundrums, there are a number of technical and data availability issues. For example, how do we estimate methane generation from our landfills? And is all the data available to support these calculations? What is routinely measured and monitored in one city, and hence easily included in the city’s footprint calculation, may not be in another.

 

These issues make comparisons between cities tricky at best and misleading and irresponsible at worst. “Low carbon” is increasingly becoming a key criterion for investors, tourists, conference and large event organisers in selecting their destinations. So the numbers are becoming increasingly relevant and sensitive as cities compete internationally not only for investment, but also for reputational advantage.

 

Recent calculations undertaken by Sustainable Energy Africa and the Energy Research Centre at UCT to support the City’s Energy Scenarios project as part of the Climate Change Think Tank give some alternative, and arguably more representative, estimates of the City of Cape Town’s Carbon Footprint:

 

6.6 tonnes CO₂e/capita (this includes emissions associated with electricity, transport fuels, fuels used for heating and cooking and landfill emissions)

7.8 tonnes CO₂e/capita (as above but also including aviation and marine emissions)

 

These figures are now below the average per capita emissions of New York, London and Tokyo (however they have been calculated), but does this mean we can suddenly relax? Certainly not. Firstly, we should question the appropriateness of a per capita measure in our very unequal society, in which the majority of citizens consume very little, thus significantly bringing down our per capita average. This suggests that some of us may still be emitting much more than our developed country counterparts. Secondly, if we look at the numbers in a different way, say as per unit of economic output or GDP, South African cities would still perform very poorly compared to our European, North American and Asian counterparts who are more efficient and produce more economic output per tonne of emissions.

 

Cape Town’s carbon footprint is and remains unacceptably high. The Mayor is correct to encourage residents to take individual responsibility, particularly those of us with unsustainable lifestyles. The City itself is taking real steps to address its carbon footprint, not least of which is a commitment to ongoing monitoring of carbon emissions, an initiative which has been in place since 2003. Understanding our carbon footprint gives us the basis from which to set meaningful targets and develop realistic and effective policy interventions.

 

Internationally, the research community is in discussion with OECD, C40, ICLEI, UNEP, WBCSD, WRI and UN-Habitat to establish an agreed standard and methodology for determining city carbon footprints. Such a standard should also make recommendations for publishing and reporting carbon footprints to minimise the misinterpretations that may arise, which in turn could have real consequences for cities.

 

The article first appeared in the Cape Times. Published with authors permission