Sunday, December 16, 2012

Getting Serious About Global Warming

First, truth in advertising. I am what modern progressives call a “global warming denier.” This is not to say that I deny the climate is changing—it has certainly changed over the course of recorded human history and even earlier.1 What I deny is that we are experiencing an abrupt and unprecedented warming period caused solely by human activity, specifically the burning of fossil fuels in the context of the rise of technology and western civilization. I have various reasons for this belief.2

Correlation is not causation. This is a principle in science, captured in the logical fallacy post hoc ergo propter hoc, or “after this therefore because of this.” Yes, carbon dioxide levels have increased in the atmosphere. Yes, temperatures seem to have risen in the 20th century. But carbon dioxide is a weak greenhouse gas, affecting heat radiation much less than either water vapor or methane, which are also present in the atmosphere. And other causes could explain the temperature rise.

One is the sun. Sunspots are directly related to solar output—more spots means more radiated energy. The number of sunspots at the peak of each eleven-year cycle, which have been recorded over the 23 cycles since spots were first noticed in the 17th century, has been gradually increasing as the sun recovered from a Maunder minimum, when very few spots were observed at all. The maximum of these increasing peaks seems to have occurred in cycle 23, at the start of the 21st century, which also coincides with the greatest recorded warming. The current cycle, number 24, may be much lower. And long-range predictions are for a much less active solar output in future cycles.

Another possible explanation lies in the tendency of weather stations to be located in or near cities. The recorded temperature rise in the late 20th century also coincides with a worldwide trend toward controlling the temperature of our indoor environments. Anyone who has stood next to an air-conditioner knows that to make the indoors cooler, you must expel heat to the outdoors. This and the longer-range urban heat island (UHI) effect—where cities are warmer than the countryside because their infrastructure includes heat-radiating pavements and building materials that retain daytime solar radiation—may contribute to the recorded temperature rise in the Industrial Age.

However, both sunspots and urban heating are also cases of correlation, not necessarily causation. For me, the origin of any change in climate may be suggested but cannot be proven except by massive experimentation. And tinkering with the climate in such experiments would likely change the nature of the conditions originally to be observed.

Computer models are not proof. All of the projections of where the recently observed warming trend will lead are based on computer modeling. Computers are not magical machines which never make mistakes, and even the most thoughtful and comprehensive models are not reality. Weather is an incredibly complex system, full of variables and influences that often conflict with and cancel each other. If it is difficult to predict weather patterns out for more than a few weeks, it is much more difficult to predict climate changes out for a century. There are too many variables we don’t understand, too many patterns we have observed for only a couple of hundred years.3

Every model makes certain assumptions and tries to control certain variables in order to avoid the chaos of this complexity. Even with the best will and intention of remaining perfectly neutral in choosing these assumptions, so as not to influence the outcome, the model make still has to make some choices. Models always come with margins of error and probability. They are rough guides, not predictions. And the more complex the system to be modeled, the more error-prone the model will be.

Consensus is not science. Much political talk about climate change mentions the “scientific consensus.” Like belief, the word “consensus” has no place in science. Until the late 1700s, when Antoine Lavoisier demonstrated the role of oxygen in respiration and combustion, the scientific consensus held that an element called phlogiston was released in a fire. Until the late 1600s, when Newton demonstrated his laws of motion, the scientific consensus held with Aristotle that objects fell to earth because they were attracted to the center of the universe, which happened to be this planet.

The only scientists who speak with authority on the matter of climate change are the tight-knit group of those who are actively sampling climate data and making models, and not all of them agree with the results of the most popular models. Ten thousand geologists, astrophysicists, sociologists, and linguists who happen to concur with the dominant view do not make it so.

But I’m willing to have an open mind. Even though I believe the case for looking ahead to the year 2100 and confidently predicting a rise in temperature of 3°C and a rise in sea level of 6 meters is far from proven, and even though I believe the resulting conditions won’t mean the end of productive human life, merely a change in the patterns we know today,4 let’s agree that carbon burning is a real problem and that we must do something serious about it starting now—if now isn’t actually too late.

But let’s also agree that the solution won’t be achieved by polite half-measures like driving a Prius, adjusting the thermostat, or remembering to turn out the lights when you leave a room. If we want to avoid the catastrophic predictions of the climate models, we’re all going to have to sacrifice. A lot.

Our civilization isn’t based largely on carbon burning because coal companies and oil companies are greedy and vicious and have duped the rest of us into doing a bad thing. We burn carbon because it’s a chemically active element that enthusiastically makes and breaks atomic bonds and releases large amounts of energy—less than the burning of hydrogen and oxygen, to be sure, but more than almost any other element. We humans arrived at burning fossil carbon deposits after millennia of trying the renewables: burning wood, grass, and various animal waxes, fats, and dungs for light and heat, or turning wheels with dammed up water and catching the wind for motive power. These energies drove the Egyptians, Persians, Greeks, Romans, and other cultures to a certain level of technology and quality of life. But it wasn’t until western civilization discovered the energy density of coal and oil that we could begin applying science and technology to solving life’s problems.

Today the U.S. economy generates more than 50% of its electricity from coal burning, and more than 90% of our transportation depends on oil. While cleaner-burning natural gas can substitute for either of these resources,5 and natural gas is becoming more available in this century because of hydraulic fracturing of deep shale deposits, using natural gas means we are still dependent on fossil carbon. To break from carbon completely requires our technology to endure a double-whammy. First, we would have to replace half of our existing generation with solar, wind, or biomass—sources that are less energy-dense and so would require more infrastructure and inputs than the coal-fired power plants they replace. Second, we would have to increase our electric generation overall, because electricity—whether by beam, wire, or battery—is the obvious replacement for petroleum in our transportation system.6 Our electric grid will have to deal with much higher demand from less energetic resources.7

I’m not saying it can’t be done. The transition can be effected over time, both by building new infrastructure and by reforming the way humans now use energy. My own favorite solution is to use photovoltaic satellites to harvest solar energy from orbit—where the radiation intensity is about ten times stronger than on the planet’s surface—both to fill the energy grid and to electrolyze seawater into oxygen and hydrogen for use as a motor fuel. These systems would be relatively inefficient but they would have the advantages of continuous operation, no moving parts, low maintenance, long operating life, and pure capital investment without operating or fuel costs. For a path to this, see my novel Sunflowers.

But over the short term, in the next ten to twenty years, which is when we will have to remake the world’s—not just the U.S.’s—energy infrastructure if we are to avoid catastrophe in the year 2100, the transition will not be gradual or seamless.

If we have to take down 50% of the U.S. electric supply over the next five or ten years—as some scientists and politicians have proposed—that means halving the amount of energy available. Unless you already have a roof made out of photovoltaic tiles, you would be faced with getting by on half the electric energy you use now. Think of the utility offering you the choice of service either mornings or evenings, or on Monday-Wednesday-Friday vs. Tuesday-Thursday-Saturday. And no falling back on lighting candles or using a gas-powered generator, as they do in Baghdad when the power’s out, because those sources would put huge amounts of carbon into the air. For the rest of the time you can either sleep or go for a walk. Think of being allowed to buy gasoline at the level of a World War II “nonessential use” ration card: four gallons a week. That’s fine if you ride a scooter and get 90 mpg, terrible if you drive an SUV and get about 17 mpg.8 For the rest of us, the choice is to cram onto inadequately designed buses and public transit systems. Air travel, railroads, and similar long-distance transportation would go under similar rationing.

Achieving an adequate response to global warming would require the federal government to assume wartime powers in peacetime. It can be done. America did it in the 1940s. England put up with wartime rationing until well into the 1950s. You could say the Soviet Union put up with conditions even more extreme during most of the 20th century. And places like Afghanistan, Ethiopia, Angola, and Mongolia live with vastly reduced carbon footprints to this day.

As far as I’m concerned, the economic catastrophe of dealing with global warming is worse than the prospect of wheat farming in northern Siberia and Saskatchewan, enduring an orderly evacuation of Florida and Louisiana, and paying for eventual redevelopment among the Hudson Valley highlands. Over the next four generations we will have time to adjust, ameliorate, compensate, and relocate. … And maybe the horse won’t sing after all.9

1. Indications from recorded history suggest warming periods in Roman times and the late Middle Ages (the latter perhaps coinciding with the collapse of Mayan civilization in Mesoamerica and other native American populations in the U.S. Southwest due to drought), and of cooling periods in the early Dark Ages and at the start of the Enlightenment in Europe (particularly the “Little Ice Age” of the 17th and 18th centuries). These indications would tend to prove that weather patterns shift every couple of centuries. We also have the fact of the corpse dated to about 3,300 B.C. in the Ötztal Alps, from a man who lay down in a hollow, died and was covered by snow that became a glacier, and was exposed by the melting of that glacier in 1991. The question, for me, is not whether human carbon burning caused the melting, but what forces caused that hollow to be free of ice 53 centuries ago.

2. And yes, the word “belief” has no place in science, which depends on observation, hypothesis, and proof through experiment. But as the following examples suggest, belief has a lot to do with the interpretation of what’s really going on with our climate.

3. Much discussion of climate change focuses on the fact that polar sea ice is visibly melting in our satellite surveys. But we’ve been watching with satellites for only about forty years, and scientists have been visiting and recording conditions in the polar regions for less than two centuries. If there are long-range cycles associated with glaciation and sea ice, we haven’t been around long enough to understand them.

4. It would be a catastrophe if the temperature and the sea rose all at once, but they won’t. Humanity will have about 90 years to adjust to fading property values in Florida, Louisiana, Bangladesh, and Vietnam and to relocate from high-value coastal cities whose waterfronts today command billions of dollars in real estate prices. Two hundred years ago, much of that land was swamp. A hundred years from now, much will lie out beyond the seacoast. But higher carbon dioxide levels and a warmer planet will provide benefits, too: accelerated vegetation growth, improved use of lands now lost to tundra and freezing winters, and lower costs for heating and snow removal. One man’s catastrophe will be another’s opportunity.

5. Cleaner burning means two things. First, breaking the hydrogen bonds around the carbon atom in methane and then replacing them with the oxygen bonds in making carbon dioxide yields more heat energy that simply forming the oxygen bond when burning coal. So natural gas produces less carbon dioxide for a given energy yield. Second, methane as a gas has none of the residual slag (i.e., non-carbon material) in unprocessed coal that puts fly ash and radionuclides into the atmosphere.

6. I have seen presentations about growing genetically modified algae in tanks that would produce and secrete an oil-like lipid that could be refined as fuel. One estimate suggested that an algae farm the size of the state of Maryland, placed under the brilliant sunshine of the Nevada desert, could replace all of the U.S.’s energy needs. I see only two problems with this. First, algae need carbon dioxide to grow, and adequate amounts would not be available in the ambient atmosphere over a Maryland-sized set of ponds; the operators would have to capture the gas elsewhere and pipe it into the pond. Second, the one thing conspicuously missing from the Nevada desert is water. Depending upon the algae’s tolerance for salt, the operators would have to pump brackish seawater in from the coast, and perhaps take the extra step of desalinating it, all at a great expense in energy. Most of these alternative energy schemes are still at the stage of conceptual engineering—which means that the proponents have worked out the basic theory, but we’re a long way from solving the practical problems.

7. What about nuclear power? Don’t get me started on nuclear! Everyone thinks utilities went off nuclear power in the 1980s after the partial meltdown at Three Mile Island. Actually, utilities stopped ordering new nuclear plants in the early 1970s, when the true economics of the fuel cycle became clear. Having been told in the ’50s and ’60s that nuclear generation would be “too cheap to meter” because of its low fuel cost, utilities started massive building programs. What became evident by the late ’60s, however, was that the combined carbon and electrical energy inputs required for mining uranium ore, purifying it to the uranium oxide called “yellowcake,” converting that to uranium hexafluoride gas, concentrating the gas in centrifuges, converting the concentrated gas to metal pellets, and assembling those pellets into fuel rods—all consumed more energy than could be obtained by fissioning the unstable uranium inside the rods. Add in the high capital cost of the power plant with all its safety measures and the problems of storing or reprocessing the hot spent fuel, and the resource becomes uneconomic. People keep proposing new designs and technologies hoping to make nuclear attractive, but it remains a complicated way to burn diesel fuel out in the desert so as not to create carbon-dioxide pollution along our coasts and rivers.

8. President Obama has talked about how gasoline prices “would necessarily skyrocket.” But that’s economically backward. Finding ways to raise the price to restrict use will simply penalize the poorest among us, force those in the middle class to make canny tradeoffs between the residual value in their SUVs and the price of fueling them, and leave the richest unaffected. If you really want to restrict the use of a commodity, you set an artificially low price and then diligently prosecute any supplier who charges more. If the federal government mandated a price of 50 cents per gallon, it would drive the oil refiners out of business. Of course, we would experience a brief black market in super-priced fuel. But the infrastructure of refining, transporting, and dispensing gasoline and diesel oil would be harder to conceal than the manufacture, smuggling, and sale of potable alcohol during Prohibition.

9. Larry Niven and Jerry Pournelle’s wonderful novel The Mote in God’s Eye attributes to Herodotus the story of a thief brought up before the king. He bargains with the king to spare his life if within a year the thief can teach the king’s favorite horse to sing hymns. When the thief is taken back to jail, another prisoner tells him what a fool’s bargain he has made, because the horse will never sing. But the thief says a lot can happen within the year: the king might die; the horse might die; or he himself might die. And maybe the horse will sing.

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