Tuesday, July 8, 2014

No quick fixes on CO2

One of the reasons the climate crises rages on with no solution in sight is that even those who passionately believe there is a problem cannot seem to focus on what (or who) is causing it.  These are people with the carbon footprint of a medium-sized Indian village who somehow believe that their sincerity plus some small symbolic action is enough to let them off the hook.  They drive a hulking SUV but rationalize this decision because they buy "protected wildlife" license plates.  They live in houses with 6000 sq. ft. (558 m2) of air conditioned living space but that's OK because they are vegetarians so their diet doesn't require cows that pass methane as part of their digestion.

Well yes, cow farts do contribute (slightly) to climate change but the big problem is still too many fires.  The biggest problem, by FAR, when discussing climate change is that folks seem utterly confused by the SCALE of the problem.  Take for example, the Very Large Crude Carrier pictured below.  Named Alexander the Great, it can haul 340,000 cubic meters of crude at a time.  That's 90 MILLION gallons—the majority of which will soon be CO2.  There are about 600 hundred VLCCs and while there is overcapacity, these ships are regularily moving product.  A coal train moves about 20,000 tons per trip and since coal is almost all carbon, that means this coal train will eventually become over 60,000 tons of CO2.  Just one proposed project of shipping coal from the Powder River Basin to the Puget Sound for export to China will require 10 loaded trains per day!

That's a lot of cow farts.  And while cow farts are methane, which is a much more serious greenhouse gas than CO2, it degrades.  By contrast, CO2 is one of the more stable molecules known to chemistry.  So while the vegetarian probably does some good by reducing the need to raise so many farting animals, he probably more than spends his "savings" buying exotic veggies in the dead of winter that have been shipped from the other side of the planet.

Fortunately, most of the climate scientists can count and they are trying to remind everyone that we should not get distracted.  No matter what else we may need to do, we simply cannot escape the problems caused by excessive CO2.  (And since CO2 is a direct result of fire, we simply cannot escape the need to rebuild our societies so that they do not need to start so many fires.  my friendly amendment)

Quick fixes won’t solve CO2 danger

By Tim Radford

New research backs up the growing body of evidence that the only way to limit global warming in the long term is a serious cut in carbon dioxide emissions from burning fossil fuels.

LONDON, 6 July, 2014 − Once again, US scientists have come to the same conclusion: there really is no alternative. The only way to contain climate change and limit global warming, they say, is to reduce carbon dioxide emissions.

It won’t really help to concentrate on limiting methane emissions, or even potent greenhouse gases such as hydrofluorcarbons, or nitrous oxide, or the soot and black carbon that also contribute to global warming. Containing all or any of them would make a temporary difference, but the only thing that can work in the long run is a serious cut in carbon dioxide emissions.

Raymond Pierrehumbert, a climatologist at the University of Chicago, combined new research and analysis and a review of the scientific literature. He reports in the Annual Review of Earth and Planetary Sciences that although livestock emissions such as methane are – molecule for molecule – potentially more potent as global warming agents than carbon dioxide, there remains no substitute for reducing the burning of fossil fuels.

“Until we do something about CO2, nothing we do about methane or these other things is going to matter much for climate,” he said.

Same solution

The conclusion is not a new one. The same solution was recommended by a Californian-led team in June, and university researchers in Oxford, UK, and Bern, Switzerland also said much the same in November last year.

Other greenhouse gases certainly contribute to global warming, and researchers have urged new ways to to be adopted to contain global temperature rises by reducing grazing herds, or by introducing better livestock management, or by making a concerted effort to limit all the other short-lived pollutants.

But, Prof Pierrehumbert argues, that is the point: methane, hydrofluorocarbons and nitrous oxides are all short-lived gases. Remove them, and there is a benefit. But carbon dioxide lingers in the atmosphere, and goes on being a greenhouse gas. Any extra CO2 in the atmosphere will go on warming the planet.

Global thermostat

A one-ton–a-year reduction in methane brings a single lowering of the global thermostat, but a reduction in carbon dioxide of one ton a year yields a climate benefit that stays. That is because, had it been emitted, it would have gone on and on raising global temperatures.

Right now, according to the Earth Policy Institute, coal still accounts for 44% of fossil fuel emissions, oil accounts for 36%, and natural gas accounts for the remaining 20%.

Subsidies for fossil fuels in 2011 added up to more than $620 billion, while renewable energy that year received just $88bn in subsidies.

In the last 200 years, the planet has warmed by 1°C, and 2013 marked the 37th consecutive year of above-average temperatures. The institute calculates that 4 billion people alive today have never experienced a year that was cooler than last century’s average. – Climate News Network more

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