4 ■ CITIES AND CLIMATE CHANGE
Th e rest of this introduction presents the main conclusions and key mes-
sages emerging from the symposium from across all fi ve clusters. Th ese are
organized broadly into sections on mitigation and adaptation, with a fi nal sec-
tion on priorities for future work.
Cities and Climate Change Mitigation
Cities are critical in global eff orts to mitigate climate change. Although ques-
tions remain about how exactly GHG emissions should be attributed geographi-
cally, most of the world’s GHG emissions are ultimately attributable to cities,
which are centers of economic activity. Cities are responsible for two-thirds of
global energy consumption, and this proportion is expected to grow further
(IEA 2008). Yet, because of their density, effi ciency, and adoption of innovations
and new technologies, cities can also provide solutions for reducing emissions.
Measuring City GHG Emissions
A fundamental step for cities when it comes to climate change mitigation is to
quantify the GHG emissions attributable to cities. Emissions must be measurable
to be manageable; cities will otherwise not be able to set meaningful targets for
emissions reductions, to track progress toward achieving such targets, or to obtain
fi nancing readily. In response to this need, much has already been achieved at the
city level. ICLEI’s (International Coalition for Local Environmental Initiatives,
now known as Local Governments for Sustainability) Cities for Climate Protec-
tion (CCP) campaign, for example, features a fi ve-milestone process that includes
establishing a baseline emissions inventory. In 2009, CCP had grown to include
more than 1,000 local governments worldwide (ICLEI 2010).
Various methodologies for measuring city GHG emissions have been devel-
oped in Europe and North America—such as Bilan Carbone, the Greenhouse
Gas Regional Inventory Protocol, the International Local Government Green-
house Gas Emissions Protocol, and Project 2 Degrees—raising questions of con-
sistency and comparability. Although most eff orts have sought to follow IPCC
guidelines, considerable variation is found among these methodologies, for
example, in terms of the GHGs covered and of the sectors (such as energy, waste,
transport, and embodied emissions in food and other materials consumed)
included (Bader and Bleischwitz 2009). Signifi cant questions exist with regard
to the treatment of emissions associated with transport to and from a city and of
emissions embodied in materials consumed within a city but produced outside it.
Another basic methodological issue lies in the defi nition of the city for the pur-
pose of measuring emissions, whether based on administrative borders, a defi ned