If you want to know how much carbon dioxide a motor vehicle emits per mile, you can create an insanely complex mathematical model to generate fake numbers in a laboratory or you can analyze actual emissions from actual cars driving on actual roads. Which method do you think will give you more accurate results? If you said, “What is real world testing, Alex?” Ding Ding Ding Ding. You’re a winner. Go to the head of the class.
It is assumed the methane emissions from industrial operations in the US amount to 8 gigagrams, equivalent to just under 9,000 tons. Why? Because that’s what industry sources say they are. But when researchers from Cornell University and the Environmental Defense Fund decided to do some real world testing, they found the reality is quite different.
Using a Google Street View car equipped with a high-precision methane sensor, they drove on public roads in the vicinity of 6 fertilizer factories in the Midwest. Most fertilizer is made from ammonia, which in turn is derived from natural gas.
“We took one small industry that most people have never heard of and found that its methane emissions were three times higher than the EPA assumed was emitted by all industrial production in the United States,” said John Albertson, co-author and professor of civil and environmental engineering. “It shows us that there’s a huge gap between a priori estimates and real world measurements.”
“But natural gas is largely methane, which molecule-per-molecule has a stronger global warming potential than carbon dioxide,” Albertson says according to Science Daily. “The presence of substantial emissions or leaks anywhere along the supply chain could make natural gas a more significant contributor to climate change than previously thought.”
What they found by driving downwind from those 6 fertilizer plants (there are several dozen fertilizer factories in the US), is that total methane emissions from that one industry alone, which is a small part of the US industrial sector, total 28 gigagrams. Compare that to the 8 gigagrams the EPA says are emitted from all industrial activity in America.
Don’t be too hard on the EPA, though. Its numbers are based on what industry tells it. To put things in perspective, the fertilizer industry tells the EPA its methane emission are just 0.2 gigagrams per year. That means actual methane emissions from making fertilizer are 140 times what the industry says they are. Apply that to all industrial activity and you soon find that rather than the 8 gigagrams a year the EPA thinks is happening, the actual number is closer to 1,120 gigagrams or 1,234,589 tons of the stuff.
“Even though a small percentage is being leaked, the fact that methane is such a powerful greenhouse gas makes the small leaks very important,” said Joseph Rudek, co-author and lead senior scientist at Environmental Defense Fund. “In a 20-year timeframe, methane’s global warming potential is 84 times that of carbon dioxide.”
So, 84 times 1,234,589 equals…..somewhere around 100 million tons of carbon dioxide. And that’s just from the US. There’s a pretty good chance fertilizer is made in other countries as well, so the methane emitted worldwide probably totals a truly staggering amount.
All of which suggests using fossil fuels to sustain the human community is a foolish thing to do. Converting to electric cars is all well and good, but it will take a full frontal assault on all fossil fuel use to save us from ourselves.
The Cornell/EDF study can be found in the journal Elementa.
Note: It is well known that I am not a world famous mathematician. Any inaccuracies in the numbers cited above I blame on my high school math teacher. Hopefully they will not detract from the overall message, which is that fossil fuels are bad for all living things, particularly humans.