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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.
Andy Skuce is a recently-retired geophysical consultant living in British Columbia. He has a BSc in geology from Sheffield University and an MSc in geophysics from the University of Leeds. His work experience includes a period at the British Geological Survey in Edinburgh and work for a variety of oil companies based in Calgary, Vienna and Quito. Since 2005, he worked as an independent consultant. Andy has published a handful of papers over the years in tectonics and structural geology that can be viewed here. He described how his views on climate change evolved in this blog post.
We have good reason to be concerned about the potential for nasty climate feedbacks from thawing permafrost in the Arctic. Consider:
The Arctic contains huge stores of plant matter in its frozen soils. Over one-third of all the carbon stored in all of the soils of the Earth are found in this region, which hosts just 15% of the planet's soil-covered area.
The Arctic is warming at twice the rate of the rest of the planet. The vegetable matter in the soils is being taken out of the northern freezer and placed on the global kitchen counter to decompose. Microbes will take full advantage of this exceptional dining opportunity and will convert part of these plant remains into carbon dioxide and methane.
These gases will add to the already enhanced greenhouse effect that caused the Arctic warming, providing a further boost to warming. There's plenty of scope for these emissions to cause significant climatic mischief: the amount of carbon in the permafrost is double the amount currently in the air.
But exactly how bad will it be, and how quickly will it cause problems for us? Does the latest research bring good news or bad?
Ted Schuur and sixteen other permafrost experts have just published a review paper in Nature: Climate change and the permafrost feedback(paywalled). This long and authoritative article (7 pages of text, plus 97 references) provides a state-of-the-art update on the expected response of permafrost thawing to man-made climate change. Much of the work reported on in this paper has been published since the 2013 IPCC AR5 report. It covers new observations of permafrost thickness and carbon content, along with laboratory experiments on permafrost decomposition and the results of several modelling exercises.
The overall conclusion is that, although the permafrost feedback is unlikely to cause abrupt climate change in the near future, the feedback is going to make climate change worse over the second half of this century and beyond. The emissions quantities are still uncertain, but the central estimate would be like adding an additional country with the unmitigated emissions the current size of the United States' for at least the rest of the century. This will not cause a climate catastrophe by itself, but it will make preventing dangerous climate change that much more difficult. As if it wasn't hard enough already.
There's a lot of information in this paper and, rather than attempt to describe it all in long form, I'll try to capture the main findings in bullet points.
The top three metres of permafrost contain about 1035 PgC (billion tonnes of carbon). This is similar to previous estimates, but is now supported by ten times as many observations below the top 1 m depth. Very roughly, the deepest deposits richest in carbon are near the Russian, Alaskan and Canadian Arctic coasts, with the poorest in mountainous regions and in areas close to glaciers and the Greenland ice sheet.
One of my pastimes is downloading data and playing around with it on Excel. I’m not kidding myself that doing this means anything in terms of original research, but I do find that I learn quite a lot about the particularities of the data and about the science in general by doing some simple calculations and graphing the numbers. There’s even occasionally a small feeling of discovery, a bit like the kind that you experience when you follow a well-trodden path in the mountains for the first time:
We were not pioneers ourselves, but we journeyed over old trails that were new to us, and with hearts open. Who shall distinguish?J. Monroe Thorington
Anyway, I downloaded some historical emissions data from the CDIAC site and played around with it. To repeat, there’s nothing new to science here, but there were a few things that I found that were new to me. First, let’s look at historical emissions of CO2 from man-made sources from 1850 to 2010. Note that for all of these graphs there are no data shown for 2011-2015.
What immediately struck me—something I hadn’t fully appreciated before—was how small oil consumption was before 1950. Both world wars were carried out without huge increases in oil use, despite the massive mobilizations of armies, navies and air forces. You can make out some downward blips in coal consumption for the Great Depression (~1930) and around the end of WW2 (~1945).
It wasn’t until after 1950 that fossil-fuel consumption went nuts. Some people have taken to calling this inflection point The Great Acceleration, there’s more on this later.
What do these emissions from different sources look like as a proportion of all human emissions over this time period?
Shell evaluates all of its projects using a shadow carbon tax of $40 per tonne of carbon dioxide. That's great. But why is the company still exploring in the Arctic and busy exploiting the Alberta oil sands?
You cannot talk credibly about lowering emissions globally if, for example, you are slow to acknowledge climate change; if you undermine calls for an effective carbon price; and if you always descend into the ‘jobs versus environment’ argument in the public debate.
Shell also has a position they call Vice President CO2, currently occupied by Angus Gillespie. Here's Gillespie talking recently at Stanford on the company's internal shadow carbon pricing strategy (hat-tip to John Mashey). It's worth watching if only for Gillespie's vivid example of the limitations of looking at averages. The slides can be downloaded here.
We found that cultural polarization over the validity of climate change science is offset by making citizens aware of the potential contribution of geoengineering as a supplement to restriction of CO2 emissions.
I will argue here that this experiment achieved no such result because the premise was wrong. Specifically, the information on geoengineering that was presented to the study participants (in the form of a fictional newspaper article) bears no relation to mainstream scientific opinion on geoengineering nor, even, to the opinions of advocates of geoengineering. Geoengineering is portrayed in the fictional newspaper article as a strategy with no uncertainty about how well it might work and, it is claimed, will "spare consumers and businesses from the heavy economic costs associated with the regulations necessary to reduce atmospheric CO2 concentrations to 450 ppm or lower". This is hardly depicting geoengineering as a "potential solution" or "a supplement" to the restriction of emissions, as is claimed in the abstract of the paper.
In fact, what Kahan et al. have demonstrated is that presenting misinformation dressed up as fact can affect people's opinions about climate change. That may be interesting as a social science experiment conducted on consenting adults, but it is not much use as a guide to effective public science communication, constrained as it is to tell the truth.
The Kahan et al 2015 paper is paywalled, but there is a 2012 version of it (updated in 2015), with the same title, similar figures, but different text, that is available online here. The study looked at two representative samples of individuals from the USA and England of 1500 each. The two samples were further split into three groups that were each asked to read one of three fictional newspaper articles. One article, used as a control, had nothing to do with climate change. The second was an article advocated tighter limits on atmospheric concentrations of CO2 (although this article contained what surely must be a typo, calling for CO2 concentrations of 175 ppm, which would send us back to depths of the last ice age). The third piece called for geoengineering on the grounds that "limiting emissions is a wasteful and futile strategy". Articles two and three both quoted a (fictional) Dr Williams of Harvard University, the spokesman of the (fictional) "American Association of Geophysical Scientists". Both of these articles contained a couple of pictures designed to appeal to or to repel people at either end of the political spectrum.
I gave a poster presentation on December 16th at the 2014 Fall Meeting of the American Geophysical Union in San Francisco. The title is: Emissions of Water and Carbon Dioxide from Fossil-Fuel Combustion Contribute Directly to Ocean Mass and Volume Increases.
You can read the abstract here and I have uploaded a pdf of the poster here. There is a picture of the poster below, click on it to make it readable, although you will need to download the pdf to make out some of the fine print.
Some of the numbers changed a little bit between the time I submitted the abstract in August and now. I found one or two small errors and recalculated the uncertainty range using Monte Carlo analysis. “Min” and “Max” values bracket the 90% confidence interval. In the title I used “directly” to distinguish the physical effects of emissions on ocean volumes from the more “indirect” (and bigger and better-known) contributions of emissions to sea-level rise via the effect of emissions on global warming.
Estimates of the incremental emission effects of individual oil sands projects like the Keystone XL (KXL) pipeline are sensitive to assumptions about the response of world markets and alternative transportation options.
A recent Nature Climate Change paper by Erickson and Lazarus concludes that KXL may produce incremental emissions of 0-110 million tonnes of CO2 per year, but the article has provoked some controversy.
Comments by industry leaders and the recent shelving of a new bitumen mining project suggest that the expansion of the oil sands may be more transportation constrained and more exposed to cost increases than is sometimes assumed.
Looking at the longer-term commitment effects of new infrastructure on cumulative emissions supports the higher-end incremental estimates.
President Obama (BBC) has made it clear that the impact of the Keystone XL (KXL) pipeline on the climate will be critical in his administration’s decision on whether the pipeline will go ahead or not. However, different estimates of the extra carbon emissions that the pipeline will cause vary wildly. For example, the consultants commissioned by the US State Department estimated that the incremental emissions would be 1.3 to 27.4 million tonnes of CO2 (MtCO2) annually. In contrast, John Abraham, writing in the Guardian (and again more recently), estimated that the emissions would be as much as 190 MtCO2 annually, about seven times the State Department’s high estimate (calculation details here).
The variation in the estimates arises from the assumptions made. The State Department consultants assumed that the extra oil transported by the pipeline would displace oil produced elsewhere, so that we should only count the difference between the life-cycle emissions from the shut-in light oil and those of the more carbon-intensive bitumen. In addition, they estimated that not building KXL would mean that bitumen would instead be transported by rail, at slightly higher transportation costs. Abraham simply totted up all of the production, refining and consumption emissions of the 830,000 barrels per day (bpd) pipeline capacity and did not consider any effect of the extra product on world oil markets.
Neither set of assumptions is likely to be correct. Increasing the supply of any product will have an effect on a market, lowering prices and stimulating demand (consumption) growth. Lower prices will reduce supply somewhere. The question is: by how much?
The Athabasca Glacier in the Canadian Rocky Mountains is probably the easiest glacier in the world to access by car. It's just a few hundred metres' stroll from the nearest parking lot on the magnificent Icefields Parkway in Alberta. The problem is, the stroll keeps getting longer by about 10 metres every year. Since 1992, the snout of the glacier has retreated about 200 metres, requiring tourists anxious to set foot on the glacier to walk a little further. The glacier has lost about 2 km of its length since 1844 (Geovista PDF).
The Athabasca Glacier seen from the access trail. This point is about halfway from the parking lot and the current snout of the glacier, which is about 200 metres away. In the centre background is the ice-fall from the Columbia Icefield. The marker shows where the glacier snout was in 1992, coincidentally the year of the Rio Earth Summit. It is just possible to make out some people walking on the glacier on the left-hand side.Click for big.
An editorial by the Editor-in-Chief of Science Magazine, Marcia McNutt, conditionally endorses the Keystone XL (KXL) pipeline. Her argument is that:
the absence of the pipeline has not stopped oil sands development and the building of the pipeline will not accelerate oil sands development;
President Obama can extract concessions from the Canadians to reduce emissions and upgrade the bitumen in Canada.
Both of these arguments are wrong; let me explain why.
Pipelines promote production
The Mildred Lake oil-sands plant in Alberta. Note the tailings pond behind the huge yellow piles of sulphur, a by-product of bitumen upgrading. The sulphur may come in handy later for use in solar radiation management. Photo Wikipedia
While attending the recent AGU conference, some of us were struck by a statistic presented by Professor Richard Alley: On average, a person's contribution of carbon dioxide waste to the atmosphere is forty times greater than their production of solid trash to landfills when measured as mass.
It can be difficult to grasp the huge quantities of CO2 that we emit. It’s an invisible gas with no odour and we are not used to thinking about amounts of gas in terms of mass. But we do have a good sense of how much solid waste we throw out, since we all have to lug our garbage to the curb. If we had to do the same with our greenhouse gases, instead of one can a week, we would have to haul forty.
Every time we see a garbage truck, let’s imagine forty others following it, all taking our carbon dioxide to a dump site. When we hear of municipal politicians struggling to find new landfill sites, imagine the problems we would have finding forty subterranean landfill sites if we ever tried to dispose of our CO2 in the subsurface instead of dumping it freely into the air.