Ethanol and greenhouse gas emissions: be skeptical

In the realm of science, it pays to go into things with an open mind. In the realm of human thought, an open mind is a rare event. We’re hardwired to immediately trust anything we agree with and are skeptical of anything we don’t. Because of that, we can find ourselves becoming very hypocritical, criticizing something for a perceived flaw while defending something else for the exact same flaw. If we were to do evaluate scientific research in this manner, we would be, well, exactly where we are now in the realm of global warming.

That’s why I was a bit disappointed to see this article up on Watts Up With That. Now, I don’t mean to criticize the site or its founder; they do excellent work. But he’s clearly not well versed in the realm of biofuels. So first, a brief background on this paper (pdf)and the controversy it is involved in. Back in early 2008, the idea of considering indirect land use change (ILUC) to determine greenhouse gas emissions from ethanol production was first introduced. Let’s ignore the idea of whether we should care about GHGs in the first place. The theory behind ILUC is simple and intuitive; if we grow more corn for ethanol here, we can’t make as much food. So in order to meet that demand, we’ll have to grow it somewhere else. And that means cutting down the rainforest or something to that effect. Obviously, the science is more complicated, and relies a lot on agricultural economic models. But that’s not really needed for now. This paper is an update of this concept. It claims that an increase from 2001 ethanol production (~1.7 billion gallons) to expected 2015 levels (15 billion gallons) will not reduce worldwide GHG emissions due to the added emissions from, well, cutting down the rainforest and stuff.

Now, because ethanol is disliked by the conservative community (and I won’t be getting into that), and because WUWT has a large conservative readership due to global warming also being disliked, this paper appears to have been readily accepted as fact. Fortunately, it didn’t appear to spread across the blogosphere, but I assume it would have been readily accepted at practically any conservative site. And all of those sites would be suspicious of the global warming crowd.

So what’s the connection here?

As everyone knows, the entire global warming theory is based on a model of the Earth’s climate. We’re supposed to trust that this model is accurate. Even if there’s no actual data to support it. Even if, intuitively, the climate is too complex to predict in a simple model. We assume the model is a perfect representation of reality.

That’s absurd, of course. That’s why I’m so skeptical of the global warming theory. And the more scientifically inclined “skeptic” sites, including WUWT, agree that it’s a huge pill to swallow.

Now do you see the connection? The whole indirect land use change theory is based on complex economic models. We’re supposed to trust that these models are accurate. Even if there’s no actual data to support it. Even if, intuitively, global agricultural economics are too complex to predict in a simple model. We assume the model is a perfect representation of reality.

Allow me to present exhibit A:

In the model presented in this paper, they assume a 17% decrease in export production from corn grain and a 12% decrease in exports of soy due to the increase in ethanol production. Makes sense, as we need a lot more corn to make all this ethanol. However, we’re about 60% of the way there (current US ethanol production is ~9-10 billion gallons). So some of these effects should start to be seen. And what have we seen instead?

Our corn and soy exports have traditionally increased or stayed constant since 2001, with only a couple weak years.

How about exhibit B?

The model starts with 2001 corn yields of 8.5 Mg/ha (about 3.8 tons/acre). They then go through some complex calculations to estimate the yield in 2015, and it looks like they assumed almost no change in yield.

However, in 2009, average corn yields were 4.6 tons/acre (a bushel is 56 lbs), an increase of about 20%.

Their model has nothing to do with reality.

And yet, because some people think ethanol is a scam (again, I’m not getting into that debate), they’ll readily accept this paper’s findings. While simultaneously rejecting global warming.

Rather silly, isn’t it?

Now, the question you need to ask yourself is this: can you trust me on this, given my own personal and financial interest in biofuels in general (not necessarily corn ethanol, but still…)? You should be skeptical of everything, including me. But at least I laid out some facts that you can investigate on your own, n’est-ce pas? Just as these people did. So who’s right?

Now, if you’ll excuse me, I have to get back to work on my own models that are not testable in reality… Ah, how we love the politicization of science…


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