Getting Cities to Zero Carbon by 2050
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It's possible. Read some recent, creative work done on a scenario developed for the City of Seattle.This article is a cross-posting in Grist, which cross-posted it from ThinkProgress Green, by Brad Johnson, who is authoring an impressive array of work.
The Seattle scenario gets to a 90 percent reduction. Clearly, a great surprise, but a 100 percent reduction, or even net positive (reducing existing carbon) is possible. This is a good step forward in a larger, on-going project, the innovation of which will be harnessed to transform the economy.
One of the troubling aspects of this work is it's apparent boldness within the "stretch" constraints of reasonableness. We need real boldness, which always looks and sceptics paint as impossible from current positions, but which will look only somewhat challenging in retrospect.
Why do we need greater boldness and apparently "impossible" results? The general recommendation that came out of the IPCC work in 200?? 7?, was to aim at a 2 degree Celsius increase in global warming, the accomplishment of which would be highly ambitious.
Subsequent dialogue critiqued this goal for two reasons. First, the associated CO2 levels and GHG reduction path only had a 50 percent probability of staying at 2 degrees or less, after which catastrophic (irreversible) climate change occurs. Second, successful stabilization at 2 degrees would result in about 400 ppm CO2, above the 300-350 ppm that many scientists came to feel is a "safe" range, both of which are above the pre-industrial level of 280 ppm, which is associated with the relatively stability of the climate we know that has proved to be relatively benign and supportive of human survival for the past 650,000 years.
Subsequent targets developed by many practitioners used whatever seemed realistic under the circumstances. They may or may not have referenced the IPCC work, but these practitioner targets rarely, if ever, equaled or exceeded the IPCC scenarios.
Unfortunately, the big policy fall-back solution of "adaptation" is really a solution of species suicide masquarading as pragmatism unless it is coupled with other policies that truly stabilize climate change at 1 degree warming or less. This scenario requires limiting peak global GHG production between 2015 and 2020, with an absolute decrease to zero by 2050 <<check this later, but zero is close to correct>>. Any scenario that pushes the peak production out beyond 2020 will stabilize climate warming at something above 1 degree C even if GHG production goes to zero by 2050, unless the decrease occurs more quickly.
As it is, if we stopped emitting GHGs today, we would face 100 years of global warming before CO2 levels returned to a safe level below 350 ppm. This is because of the lag times overwhich CO2 remains in the atmosphere <<provide more details later>>.
To push the challenge further, accumulating evidence since the IPCC report indicates that climate change is occurring more quickly than in the IPCC models. Thus, the effective response to avoid catastrophic climate change of our BAU scenario requires compressing the GHG reduction scenarios of the IPCC modelling. Limit the peak sooner (2012-2015!) and reduce to zero more quickly and sooner (2030?)!.
Given humanity is 50 years late in responding to this issue, given that doing so will require and result in an economic transformation that promises greater levels of prosperity and security, for what are we waiting? Do it ASAP! But that is just my opinion, or is it? Read/listen to Lester Brown, Thomas Friedman, and Peter Senge <<link forthcoming-google Necessary Revolution in the meantime>>, the three great synthesizers of our day that provide a detailed account of the climate change and sustainability challenges and how responding to them will require and create higher quality, prosperous and secure regenerative economy and society.
See this other post for more precision on the scenarios and citations.
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