- Measures that could limit the high economic and health costs of rising urban temperatures are a major priority for policy makers
- Changing 20 per cent of a city’s roofs and half of its pavements to ‘cool’ forms could save up to 12 times what they cost to install and maintain, and reduce air temperatures by about 0.8 degrees
May 29, 2017 University of Sussex see full article here
- Overheated cities face climate change costs at least twice as big as the rest of the world because of the ‘urban heat island’ effect, new research shows. …The urban heat island occurs when natural surfaces, such as vegetation and water, are replaced by heat-trapping concrete and asphalt, and is exacerbated by heat from cars, air conditioners and so on. This effect is expected to add a further two degrees to global warming estimates for the most populated cities by 2050. Higher temperatures damage the economy in a number of ways — more energy is used for cooling, air is more polluted, water quality decreases and workers are less productive, to name a few….Although cities cover only around one per cent of Earth’s surface, they produce about 80 per cent of Gross World Product, consume about 78 per cent of the world’s energy and are home to over half of the world’s population. Measures that could limit the high economic and health costs of rising urban temperatures are therefore a major priority for policy makers…The cheapest measure, according to this modelling, is a moderate-scale installation of cool pavements and roofs. Changing 20 per cent of a city’s roofs and half of its pavements to ‘cool’ forms could save up to 12 times what they cost to install and maintain, and reduce air temperatures by about 0.8 degrees….
Francisco Estrada, W. J. Wouter Botzen, Richard S. J. Tol. A global economic assessment of city policies to reduce climate change impacts. Nature Climate Change, 2017; DOI: 10.1038/NCLIMATE3301
Climate change could make cities 8C hotter – scientists Monday 29 May 2017 Guardian UK
Under a dual onslaught of global warming and localised urban heating, some of the world’s cities may be as much as 8C (14.4F) warmer by 2100, researchers have warned. Such a temperature spike would have dire consequences for the health of city-dwellers, rob companies and industries of able workers, and put pressure on already strained natural resources such as water. The projection is based on the worst-case scenario assumption that emissions of greenhouse gases continue to rise throughout the 21st century. The top quarter of most populated cities, in this scenario, could see temperatures rise 7C or more by century’s end, said a study in the journal Nature Climate Change.