Urban-Scale Evaluation of Cool Pavement Impacts on the Urban Heat Island Effect and Climate Change

We implemented a context-sensitive
and prospective framework to
assess the global warming potential (GWP) impacts of cool pavement
strategies on specific roads for different cities. The approach incorporates
several interconnections among different elements of the built environment,
such as buildings and urban road segments, as well as the transportation
fleet, using specific building and pavement information from an urban
area. We show that increasing pavement albedo lowers urban air temperatures
but can adversely affect the building energy demand in the areas with
high incident radiation exposure. The heating energy savings and the
radiative forcing effect improve the GWP savings in cold and humid
climate conditions. The total GWP savings intensity is sensitive to
the city morphology and road traffic. The probabilistic results show
that cool pavement strategies can offset 1.0–3.0% and 0.7–6.0%
of the total GHG emissions of the U.S. cities Boston and Phoenix,
respectively, for a 50-year analysis period. The worldwide range of
savings can be as large as 5.0–44.7 Gt of CO2 eq.
A paradigm shift in pavement strategy selection is required in most
neighborhoods.