Curvilinear Thinking on Climate Change

The MPG Illusion -- Needing Math?

Now that gas is almost $5.00 per gallon many people seem to be more than a little worried, if not about global warming than simply about the price of gas. Of course some lobbyists and commentators continue their efforts to preserve status quo, whole hog energy use that exacerbates global warming. These efforts ultimately undermine independence from foreign oil and adaptation of measures that would stem to pace of global warming. In "Communicating Climate Change", last year I wrote:

"If we've moved beyond the climate change "debate", however, as I argue we have, we've only entered another stage. I'm not sure what to call it, but it if we appropriated something like the familiar five stages of dealing with catastrophe- denial, anger, bargaining, depression, and acceptance, then maybe people have moved on to some sort of denial/bargaining phase. People get ideas about how we can buy our way out, with some carbon credits, some alternative energy, or some prizes. Again, this is procrastination. If buying our way out doesn't work, at least we've bought some time."

Science published an article the other day in their Policy Forum section from a couple of Duke business professors. "The MPG Illusion" (June 20th) argued that people misunderstand the miles per gallon (mpg) standard. The authors ask the question, if you had a choice of upgrading one of two cars with a car with a better MPG rating which would you replace? Unlike Europe, where the mileage standard is expressed in liters per 100 kilometer, in the US, miles per gallon (mpg) refers to the distance a gallon of gas will achieve in a vehicle: 1000 gallons per 10,000 miles equals 10mpg. Not very many people understand that, according to their poll.

Increases in mileage are calculated so that 30% better gas mileage means 23% less gas used. 30% greater "mpg" means greater distance per gallon of gas, instead of traveling 100 miles you would now be able to travel 130 miles, so 100%/1.3 = 76.9, 23% less fuel. Most people assume the relationship between miles driven and gas consumed is linear, but its actually curvilinear. From there, the authors argue that small upgrades, say from a "10 mpg" rated car to a "20 mpg" car, may save the consumer more on gas than upgrading from 25mpg to 50mpg.

Their goal was to see whether people ranked choices in mathematically correct ways and so they structured their question carefully. But if their point is to illustrate that the standard is deceiving, as they say in the video, why do they need to publish an article in Science, and perambulate through all the math and graphs?

Promoting a clearer standard isn't their only goal. They open their Science piece criticizing a NYT columnist who questioned the sense of giving an IRS hybrid car tax break to people who buy "a hybrid Dodge Durango that gets 14 miles per gallon instead of 12 thanks to its second, electric power source."

But doesn't the NYT author have a point? Why would the government offer a credit? The authors acknowledge this: "The basic argument is correct: The environment would benefit most if all consumers purchased highly efficient cars that get 40 MPG, not 14, and incentives should be tied to achieving such efficiency." This hat tip to clear thinking is only 27 words of their Science article, versus 1708 words explaining calculations that in effect justify why upgrading from a 1978 Cadillac or your grandpa's farm tractor to an SUV is a choice that consumers should feel good about. While the question is carefully constructed around consumer choices about two cars driven equally and yields a conclusion showing that consumers don't understand mpg math, why this question?

In effect, the authors' piece would be brilliant in a Dodge Durango or Ford ad to boost those double digit sales drops. But back to the New York Times article. Why wouldn't a person upgrade from a 10mpg car to a 50mpg car? A 10 mpg car would use 1000 gallons per 10,000 miles, and a 50mpg would use 200 gallons per 10,000 miles. 800 fewer gallons of gas. That much less pollution. $5,000 of gas, versus $1,000. Why can't we shoot for that?

Consumers are making exactly these choices. Ford sold 55% fewer SUV's last month, and 40% fewer pick-ups then in the previous year. In our last post we quoted from the NYT article, America, Asleep at the Spigot", in which Congressman Dingell (D-MI) [correction, 11/07/08], told the NYT" "He likes it sitting in his driveway, he likes it big, he likes it safe". It seems that "He" is changing "His" mind about "Big" and "Safe", when faced with $150 per fill-up. "He" is choosing a Prius instead of a pick-up.

Global Warming: Too Much Evidence

There's a direct correlation between energy cost and use, just as there's a direct correlation between increased cigarette taxes, and decreased smoking. Lobbyists routinely argue the opposite in order to justify low taxes and minimal regulation. But the fact that car owners are switching to more efficient cars is a market coup for global warming as well as free-market advocates. This should please all of us who support liberal economic policies, as well as "let the market" commentators. But paradoxically, some of columnists are still stuck with in their delusional refrains from 2005.

A Wall Street Journal blogger now claims there's too much evidence on global warming, so much that it's not believable (WSJ July 1, 2008, "Global Warming as Mass Neurosis"). "What isn't evidence of global warming?" he asks. My favorite! For years it was, "there is not enough evidence". And now, simply invert the sentence to arrive at your next phase of denial. Last year when you pulled his string he said "Not Enough Evidence!!!" and alarms rang -- Whooop! Whooop! Whooop! This year they retooled, so yank the cord to hear, "Too Much Evidence!!! Whooop! Whooop! Whooop! American Girl could immortalize his likeness as the Denier Doll from the historical series "When Carbon was King" or "When the Air was Breathable". Of course next he instructs: "[s]o let's stop fussing about the interpretation of ice core samples from the South Pole". He will no doubt shuffle around in these arguments until the water's licking up around his ankles.

He insists that global warming is either a socialist, religious, or psychological affront to our way of life by those who believe that prosperity is corrupt. Last year we wrote in "Climate Change: Fueling the "Debate", "if you're crazy-dizzy snapping your head around to follow first the one side, than the other, simply follow the money for the truth." Perhaps our columnist hasn't invested in any emerging energy markets.

Sanity and Samsø

As last year and the year before, available at our fingertips, along with the woulda-coulda-shoulda crowd and the bloviators, is the full range of serious and interesting discussions. Consumers are making changes around global warming not only by buying Priuses, but by using alternative energy sources or cutting back their energy use.

In the New Yorker this month, Elizabeth Kobert wrote a great article called "The Island in The Wind". The first part of the article was about the residents of Samsø an island in Denmark that progressed from consuming enough oil and electricity to provide energy for 4,300 people, to generating enough renewable energy through wind turbines and other sources to produce energy for the whole island and sell some back to the grid. The island accomplished this with a combination of initiative, work, leadership and community investment, but with no initial motivating monetary reward.

While generating their own energy however, the islanders didn't reduce their consumption. For that part of the story Kolbert goes to Switzerland, where the 2,000-Watt Society aims to motivate people to reduce energy consumption to 2,000 Watts per person with only 500 Watts consumed from non-renewable sources. Scandinavians consume 6,000 Watts per year per person, and US citizens consume ~15,000 Watts per year per person, so the 2,000 Watt goal gives some populations room to grow while others should strive to cut back on energy use.

When we wrote "Sea Change or Littoral Disaster" in 2006 it seemed like we'd never turn a corner. We wrote "We need no more evidence. We have decades of studies indicating that our lives will change, but its easier to wait for another headline and hope a miracle intervenes, if nothing else than in the guise of government action." Times are decidedly more optimistic. Of course there the same gradient of action, inaction, denial, and procrastination, but when I reflect on the general attitudes of the past couple of years I'm amazed at all the change happening in 2008.

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