New York City could cut greenhouse gas (GHG) emissions by 90% by 2050 by implementing a portfolio of energy reduction measures using existing technologies, according to a report released last week by the Urban Green Council.
The Council’s underlying arithmetic is emblematic of the prevailing portfolio-based approach to climate change mitigation – namely, strategies for reducing GHG emissions. The so-called “stabilization wedges” concept was introduced nearly a decade ago by two Princeton professors, Rob Socolow and Stephen Pacala, in a paper published in Science, “Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies.”
The wedges paradigm, which provides a framework for formulating emissions reduction strategies based on currently available technologies, quickly became the gold standard in the field of climate change mitigation. And for good reason. It was (and still is) a very effective and pragmatic way to package discrete mitigation strategies into a single platform, which could be optimized in much the same way that investment portfolios are optimized.
If Superstorm Sandy taught us anything, it was that mitigation by itself will neither prevent climate change from wreaking havoc on society nor protect us when it does. Indeed, climate change mitigation measures may make the damage and disruption caused by climate change considerably worse in some circumstances. Pro-active adaptation to climate change – or, strategies for enhancing society’s ability to cope with the negative effects of climate change – begins with breaking down the mitigation stovepipe.
The climate system is not a stovepipe and any policy response to climate change that pretends otherwise is likely to be the road to ruin. This has vast implications for energy and urban planning protocols, including the Urban Green Council’s 90×50 vision.
By framing decisions and objectives narrowly, the wedges paradigm (at least as applied in scores of analyses like the 90×50 report) prevents robust consideration of the complexity and uncertainty inherent in responding to climate change.
By way of example, imagine choosing between two policy options – A and B – for responding to the threat of global warming. Option A would reduce GHG emissions by 90% by 2050, but only if the future unfolded as anticipated. Option B would reduce GHG emissions by 70% by 2050, but would do so across a range of possible futures. A wooden application of the wedges model would prioritize the former over the latter.
In Power to the Edge, David Alberts and Richard Hayes, leading U.S. military strategists at the U.S. Department of Defense’s Command and Control Research Program, emphasized the shortcomings of optimization strategies:
This fixation on optimality often results in the selection of an option that sacrifices agility in the hopes of achieving the best possible result in the current case. For example, such options include the selection of a military option that will work if an adversary does what is expected, a network that has only the links that are expected to be used, or a process that restricts participation, but is fast. When things go right, they go very right. When things do not go as anticipated, they may not work at all. This form of gambling is not a good bet . . . .
The same can be said – and said emphatically – about the prudence of gambling in this form in the context of climate change.
By deepening reliance on the conventional electric grid and eliminating the use of natural gas in New York City buildings altogether, the Council’s mitigation strategies would likely exacerbate the vulnerability of New York City’s energy systems to extreme weather and other adverse impacts of climate change.
In 2007, the Intergovernmental Panel on Climate Change concluded that: “It is essential to look at how the various components of the energy-supply chain might be affected by climate change . . to ensure that any mitigation programs adopted now will still function adequately if altered climatic conditions prevail in the future.”
“The tradeoffs between resilience and efficiency are seldom acknowledged in the planning process,” P. H. Longstaff, an associate professor at Syracuse University, concluded in an essay published by George Mason University’s Center for Infrastructure Protection.
Rather than masking the trade offs between efficiency and redundancy, the wedges should illuminate them.