Today’s review article (partly) turns on its head the assumption by urban planners that intensification of the urban population is a worthy objective from an environmental and infrastructure point of view. This is based on a comprehensive cradle to grave assessment of CO2 emissions. Results indicate that a densely populated population core emits more than their suburban cousins for all categories of emissions except ground transportation because of the higher consumption of goods and services there. This conclusion may not be true of cities where the high consumer population lives in the suburbs but is a clear signal for planners to make their assessments on more than a transportation basis. Density may be a preferred option for other reasons but not necessarily for climate mitigation.
Key Quotes:
“Contemporary urban planning follows design principles that are often referred to as the ‘five Ds’, namely, density, diversity, design, distance to transit, and destination accessibility”
“dense urban structure reduces vehicle miles traveled (VMT), which in turn reduces CO2 and other air emissions..At the same time, it is known that urban development patterns have a larger influence on daily commuting, while recreational transit is more dependent on the socioeconomic background of the consumer”
“carbon dioxide equivalent (CO2e) emissions are substantially higher in the dense downtown area than in the surrounding suburbs, which is suggested to imply that the increased consumption due to the higher standard of living increases emissions more than the higher density is able to reduce them.. carbon load of 14.7 ton CO2e per capita in Helsinki DT with nearly 10 000 inhabitants km−2 compared to 12.0 ton CO2e in the Helsinki SU with less than 3000 inhabitants km−2”
“climate policies should give higher priority to the energy consumption of buildings, to alternative energy production and distribution modes, as well as to low carbon consumption within the city”
“dense and diverse urban structure can be justified from a number of other ecological and social considerations such as exploiting readily available infrastructure, protection of wetlands or other natural habitats, or restoring greenfields for recreational use”
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- Car makers 'reducing emissions' (autonetinsurance.co.uk)
- Wastewater recycling can multiply greenhouse gas emissions (eurekalert.org)
- Carbon Reduction Targets: How Do Different Sectors Compare? (greenresearch.com)
- Business insurance holders 'need single emissions reporting format' (premierlinedirect.co.uk)
- Electric cars key to greener future (autonetinsurance.co.uk)
- Steps to reduce overall carbon emissions associated with concrete pavements by about 50 percent (nextbigfuture.com)
- Canada's Emissions Trends (climateinsight.wordpress.com)
- EU Is Overrating Biofuels Benefits (technologyreview.com)
- Are Motorcycles "Greener" Than Cars? (volokh.com)
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