London scoping - ukcip

Final Report
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explored in Tokyo include ‘green roofs’, i.e. using vegetation grown on roof tops to limit heat
gain and to increase heat loss by evapotranspiration from the roots of the trees and shrubs. Such
green roofs do appear to have had some success in temperature moderation within buildings, but
one downside is that they increase the humidity of the air in the immediate vicinity of the
building. Chicago also has a programme of encouraging green roofs (www.cityofchicago.org/
Environment/Airpollution). The Japanese Construction Ministry is also investigating
constructing a large heat exchange system covering some 123 hectares in the centre of Tokyo,
including the Marunouchi business district and Ginza shopping area (Reuters 2002). Water
would be pumped in buried pipes and would collect waste heat from air conditioning systems
before being sent to a heat exchange system on the Tokyo waterfront, where cooler sea water
would be used to absorb the heat. The cooler water would then be pumped back to collect more
waste heat from the city, cooling the local air temperature by between 0.4 and 2.5°C. The
scheme is currently only an idea and would be expensive, costing about $350 million dollars
(pay back time of 30 years due to lower air conditioning costs) (Reuters 2002).
Social Responses to Warmer Domestic Properties
A larger proportion of Londoners live in flats and apartments and in multiple occupancy
dwellings than elsewhere in the UK. This limits the responses which can be undertaken to some
extent, since you cannot simply ‘go into the garden/backyard’ to cool down. Very few of the
flats being built in London have balconies, but this is a well established method for coping with
high summer temperatures used in buildings on the continent. In the social impacts workshop
conducted during this study, there was a joke about ‘Affordable Balconies’ for London, but
more seriously it was proposed that building guidelines might explore whether outside space
could be enhanced for all new domestic and commercial property.
Another obvious adjustment to hotter weather is to open windows and doors to let cooler air
replace hotter inside air. This is not always feasible, however, due to the greater risk of crime
arising from open doors and windows, as well as traffic noise and traffic-related pollution. One
finding from the heat wave in Chicago in the mid-1990s was that poorer households felt less
able to open doors and windows because they felt more vulnerable to crime (stakeholder input
to workshop, May 2002). Given that security and crime consistently emerge as prime concerns
of Londoners, and as the top priority for action to improve London as a place to live (MORI
2002), the reluctance to opening doors and windows could easily be as real a phenomenon in
London as it is in cities such as Chicago. This would affect less affluent neighbourhoods
disproportionately and hence increase social inequity.
A further adjustment to hotter weather is be outside more often. This would require dwellers of
flats and apartments without balconies to utilise communal space, or public spaces such as parks
and gardens, so increasing pressure upon these. Whether local parks would be sufficient to cope
with a greater demand for more outdoor spaces is not known and depends upon behavioural
change which is impossible to predict. There might well be ‘improvisation’ in such a situation,
utilising street corners, areas outside shops, or outdoor facilities in pubs and cafes. Access to
such areas would not be even, however, since they may not be designed to cope with those with
disabilities for example. Also, such impromptu congregations are unlikely to be welcomed by
all local residents, some of who would perhaps complain about noise and disruption, feel
threatened, etc. An interesting question is whether newly-built housing today should
incorporate design aspects that take account of the likely greater demand in future for more
outdoors living. This might be at the individual dwelling level or communally, e.g. shared areas
of barbecues, outdoor get togethers and entertaining, etc. In Australia, for instance, public