Tuesday, June 2, 2015

Climate Change Part 20: Mitigation

--> Note: This program first aired March 28, 2015.

We’re reaching the end of our story about climate change, and the question that remains is: What do we do about it? Last week we looked at various proposals for geoengineering, methods of mimicking and manipulating natural processes in order to accelerate the removal of carbon dioxide from the atmosphere. Next we review the Intergovernmental Panel on Climate Change’s 2014 report on climate change mitigation efforts. The IPCC defines mitigation as anything that reduces the sources or enhances the sinks for green house gasses. Geoengineering is all about enhancing the sinks, so today we focus on reducing the sources.

To read an IPCC report is to realize there is not just one model or one set of predictions out there. You have to sift through 8 or more different alphanumeric codes, each one representing a different climate mitigation scenario, from good to bad to the worst; business as usual. Policy makers and scientists have recently coalesced around one scenario in particular as the one we should be aiming for as we move into the future. Unless there is some kind of zombie apocalypse, the best case scenario is to reach a stabilized carbon dioxide level of 450 ppm by the year 2100. The thought is that this carbon dioxide level would keep the world at a 2 degree Celsius or less average temperature increase, an increase that would change things, but hopefully not catastrophically. You may have heard the figure 350 ppm floating around out there, it’s also the name of a significant climate action coalition who’s goal is to promote fossil fuel divestment and get the Earth back to an atmospheric carbon dioxide level of 350 ppm—the last level thought to be “safe” for sustaining life as we knew it on the planet. We’ve blown past 350, hitting a historic 400 this past year. At this rate, 450 sounds pretty optimistic to me.

So how does the IPCC propose we do this? By reducing carbon dioxide, and other green house gas emissions. When quantified, it means, by the year 2050, green house gas emissions 40-70% lower than emissions from 2010. That sounds like a big drop doesn’t it? Where are we going to cut all these green house gas emissions? If you look at the 2010 spectrum of green house gas emissions, you will see different economic categories of sources: the energy supply sector, agriculture/forestry, industry, transportation, and buildings. The largest source of these is easily the energy supply sector, basically where heat and electricity are generated, electricity that then goes to various places, including industry, buildings and a little bit of transportation to get used. Fossil fuels are used to generate this energy. Energy is what fuels the modern economy, it was easy access to energy that allowed the industrial revolution, and it is continued easy access to energy that enables our extremely comfortable standard of living in the industrialized 21rst century. Economic and population growth are the “most important” drivers of increases of carbon dioxide emissions from fossil fuels. When we look to the energy supply sector to decrease its emissions, we need to remember that economic growth is what raises people out of crushing poverty, and with populations increasing, more people than ever need that lift. This is why developing nations balk at strict emissions agreements. They don’t see a viable path to economic development without an energy supply driven by fossil fuels, and thus by turning away from a fossil fuel economy, they doom their citizens to continued poverty. What is clear at this point is that “peak oil” or “peak any fossil fuel” is not going to be the limiting factor in the fossil fuel economy in any time frame relevant to the current climate situation, so decarbonizing the economy in a way that can still allow for economic development, especially in the developing world, will have to be done consciously, by choice. The IPCC estimates that we need 3 to 4 times the amount of zero or low carbon energy (from sources including renewables, nuclear power and fossil or biofuels that utilize carbon capture and sequestration technology), and to do that significant investment is needed, particularly in the next two decades.

In other words, there is no time to waste. The IPCC report says it best, and I quote it here: “Delaying mitigation efforts beyond those in place today through 2030 is estimated to substantially increase the difficulty of the transition to low longer-term emissions levels and narrow the range of options consistent with maintaining temperature change below 2 °C relative to pre-industrial levels.”  Clearly now is the time. Right now.

Even with this imperative, it was heartening to read the Summary for Policy Makers version of this report, in that the work is clear, what needs to be done is clear, and it some how miraculously, while an enormous task, doesn’t seem impossible. When you see the weird volatility in oil prices, and the industry’s response to low oil prices, investment in renewables makes a lot more sense. The divestment movement seems a little less out in left field when viewed from standing on a $40 barrel of crude oil. What this report does is help triage our mitigation efforts, after reading it I can see that we need to focus our big efforts on the energy sector. In terms of global mitigation that needs to be our focus in the next twenty years if we are to have any hope of holding off the changes that could diminish the quality of life for all of us living on this planet. Reduce, reuse, recycle, yes, but also and perhaps more importantly, support zero carbon power initiatives too.


IPCC “Climate Change 2014L Mitigation of Climate Change http://mitigation2014.org/

Science Daily digest of the slowing of the Gulf Stream (includes link to original study): http://www.sciencedaily.com/releases/2015/03/150323132746.htm

About the “Pause” in global warming from the Pacific oscillation http://www.decodedscience.com/global-warming-ocean-heat-sink/49728

The Skeptical Scientist take on the Pacific oscillation: http://www.skepticalscience.com/print.php?n=2647

A really different take on climate mitigation, and our individual responsibility for it: https://orionmagazine.org/article/forget-shorter-showers/