10 ■ CITIES AND CLIMATE CHANGE
Understanding Climate Impacts in Cities
One basic requirement for adaptation planning in any city is a sound analysis of
possible climate impacts. In itself, this is a challenge of substantial complexity—
there is considerable uncertainty on what future climate impacts might be for
a given city, although our knowledge and modeling capabilities are constantly
improving, for example, with downscaling climate models. In “Urban Heat
Islands: Sensitivity of Urban Temperatures to Climate Change and Heat Release
in Four European Cities,” McCarthy and Sanderson show how urban areas can
be included in regional climate models, using the cases of Athens, Cairo, Lon-
don, and Moscow. Th e authors focus on the “urban heat island” eff ect, which
arises from heat released through human activity in cities, such as the heating
and cooling of buildings, traffi c exhaust, and even human metabolism. Urban
buildings and structures absorb heat during the daytime and release it at night,
leading to an increase in nighttime temperatures. Th e authors caution that
future heat waves may be underestimated if fi ner features at the urban scale are
not included in model simulations. Th e potential for applying this analysis to
other cities is considerable and would enable individual cities to fi ne-tune their
knowledge of potential changes in local temperatures.
In general, modeling eff orts are well situated within a broader fi eld of work
on assessing climate risks in cities. Bulkeley and others and Heinrichs and oth-
ers analyze how cities are already anticipating and planning for future climate
impacts. One of the symposium’s commissioned research papers by Mehrotra
and others also addressed this need: It presented a framework for climate risk
assessment in cities and emphasized the importance of distinguishing among
the diff erent types of risks faced by diff erent cities. Th e forthcoming Urban Risk
Assessment, an approach for assessing disaster and climate risk in cities, is being
developed by the World Bank with UNEP and UN-HABITAT and proposes a
unifi ed methodology for this purpose. It represents another important step in
bringing the fi elds of disaster risk management and climate change adaptation
closer. Although both communities of practice have the common aim to support
decision making under uncertainty, they have largely operated in isolation from
each other until recently (Tearfund 2008).
Climate Adaptation and the Urban Poor
An important issue when considering climate change adaptation, especially in
developing countries, is to ensure adequate focus on the urban poor. Signifi cant
literature can be found on the economic impacts and costs of adaptation to
climate change (see, for example, World Bank 2010b). Evidence is also avail-
able that the number of people aff ected by disasters is on the rise, and within