Demographic Transition From Rural to Urban Areas

From 2000 until 2030 the urbanized areas will be nearly tripled1 because of the demographic transition from rural to urban. The use of dark building materials, such as asphalt and concrete, leads to a lower albedo in urbanized areas than in natural environment2, fostering local and global warming. In turn, the increase in urban albedo might support climate stabilization efforts3. Here, we investigate the potential effect of the increase in albedo in a representative set of European cities relying on instantaneous radiative forcing (IRF), urban cooling and the consequent effect on mortality, ozone formation and energy use. Apart from any geographical distinction, cities show that the increases in albedo in compact cities have a cooling potential and may provide better living conditions being motivating for local governments. Besides, wide cities may have a better potential on IRF contributing to purse global common good. Altogether, stratified and multilevel policies might be applied to mitigate global and local climate according to the level of the potential deriving benefits and co-benefits.

The contribution of cities to global climate change mitigation and energy use gains increasing attention4. As progress in addressing climate change remains stuck in complicated negotiations5 on an international level, cities might be the appropriate spatial scale to address multi-faceted challenges such as climate change6. Cities’ decision-makers successfully implement local climate-change mitigation measures to pursue co-benefits and cost-savings6 but reluctantly react to top-down imposed mitigation and adaptation plans7. However, as the efforts of climate change mitigation remain local, any single city will hardly leave measurable benefits...

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...nts. Sol. Energy doi:10.1016/j.solener.2012.07.003

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