Is Global Warming For Real?

by Bob Seitz

January 5, 2005

One of climatologists' worst nightmares about global warming is that it might possibly have begun to feed on itself, leading to runaway global warming. The searing hell that is Venus is mute testimony to what a runaway greenhouse effect can be like.

What I know about climatology could fit on the back of an envelope, with room left over for a long grocery list, but armed with my trusty pocket calculation and unbearable chutzpah, watch, as I rush in where angels fear to tread.

The Total Weight of the Earth's Atmosphere Is About 5 Quadrillion Tonnes

The Earth has a radius of about 4,000 miles or about 6,400 kilometers, giving it a 4pr2 total surface area of approximately 500 million square kilometers. The pressure at the Earth's surface is about 14.7 pounds per square inch or about one kilogram per square centimeter. This is the weight of the column of air that lies over each square inch/centimeter on the Earth's surface-- roughly 10 metric tons (tonnes) per square meter, or 10 million tonnes (metric tons) per square kilometer. Multiplying this by 500 million square kilometers yields 5 quadrillion tonnes for the total weight of the Earth's atmosphere.

The Total Weight of the Earth's Atmospheric Carbon Is About 750 Billion Tonnes

The 2005 atmospheric concentration of carbon dioxide was 380 parts per million by volume, or about 550 parts per million by weight. Multiplying 0.55 X 10-3 by 5 quadrillion tonnes leads to 2.75 trillion tonnes for the total weight of the carbon dioxide in the Earth's atmosphere.... and this happens to be the number officially quoted for the weight of the Earth's atmospheric carbon dioxide. Since the carbon in carbon dioxide weighs 3/11ths much as the carbon dioxide, the total current weight of carbon in the Earth's atmosphere is roughly 750 billion metric tons, corresponding to the above-mentioned 380 parts-per-million (ppm) concentration.

The Increase in Atmospheric Carbon Over the Past 250 Years Has Been About 264 Billion Tonnes

It's estimated that about 264 billion metric tons of carbon has been added to the Earth's atmosphere since 1751 (http://cdiac.esd.ornl.gov/trends/emis/tre_glob.htm).

Three-Fourths of the Carbon Added to the Earth's Atmosphere Since 1751 is Still There

The pre-industrial-age concentration of CO2 was about 280 ppm (through 1750), corresponding to a total atmospheric carbon level of about 550 gigatonnes of atmospheric carbon. In other words, since 1751, about 264 gigatonnes of carbon has been added to the atmosphere, and it's raised the atmospheric carbon inventory by 200 gigatonnes... about ¾ths of the carbon added over the past 250 years is still in the air, and about ¼ has been removed.

Outgassing of Methane from the World's Frozen Tundras

A climatological survey of the frozen wastes of western Siberia over the last few years has revealed that they have warmed about 5º Fahrenheit since 1965 (http://www.newscientist.com/channel/earth/mg18725124.500). They are thawing, and are now dotted with thousands of summer lakes. These lakes are outgassing methane, which is about 20 times as effective in promoting global warming as is carbon dioxide. Similar outgassing may be found in eastern Siberia, where methane is bubbling up out of the ground summer and winter.... outgassing sufficiently rapidly that it's keeping the ground from freezing. A similar situation exists in Alaska, and presumably, across northern Canada. The total amount of methane that's locked up in permafrost in western Siberia is estimated at 70 billion tonnes (one metric ton = 2,200 lbs.), with a worldwide total of about 280 billion  tonnes of methane stored in frozen soil. Since methane is 20 times as effective as carbon dioxide in trapping heat, that 280 billion tonnes would be equivalent to about 5.6 trillion tonnes of carbon dioxide, or a little over twice as much as the atmosphere's current store.

Is there a silver lining to this dark cloud? If these peat bogs dry out, then their methane will oxidize in situ and will be released in the form of carbon dioxide. Only if they remain wet will they deliver their methane to the atmosphere.

Permafrost isn't the only massive source of planetary methane. Some studies suggest that there might be 10 trillion tonnes (http://www.sciencenews.org/pages/sn_arch/11_9_96/bob1.htm) of methane trapped in seafloor ice clathrates (equivalent in heat-trapping effects to 2,000 trillion tonnes of CO2), or nearly 750 times the CO2 presently found in the atmosphere. Professor James P. Kennett has suggested that slight warming of ocean waters may have triggered clathrate releases that may have further exacerbated global warming several times over the last 70,000 years. Obviously, if this is so, it didn't lead to runaway global warming, though it may have contributed to mass extinctions in the past.

Whoops! This morning while writing this article, I came upon a just-published news release, "Past gives clue to climate impact" (http://news.bbc.co.uk/1/hi/sci/tech/4582872.stm), on the BBC website reporting the results of a just-completed study of the mass extinction that wiped out the dinosaurs at the end of the Mesozoic Age. This article states,

"The reason why temperatures shot up during the Pleistocene-Eocene Thermal Maximum (55,000,000 years ago, when the dinosaurs died out) are unclear; but carbon dioxide concentrations in the atmosphere appear to have been extremely high, about a thousand times higher than currently. The suspicion is that some kind of feedback mechanism may have been involved. One theory is that an initial warming changed the distribution of heat in the oceans so that deposits of gas hydrates on the sea floor were released, with carbon dioxide and methane rising to the surface and entering the atmosphere, causing further greenhouse warming.".

Apparently, 55,000,000 years ago, clathrates were released from their undersea storage bins, raising the concentration of carbon dioxide in the atmosphere to something like 38%. Happily, this didn't cause runaway global warming, and mammals survived to repopulate the Earth.

Is the Temperature of the Earth's Atmosphere Actually Rising?

One of the major arguments against global warming was negated in August, 2005. Radiosonde measurements of atmospheric temperatures made during the 1970's had shown temperatures that were as high as those measured today.  Then, last August, two independent reviews found  that weather balloons in the 1970's employed temperature gauges mounted on the outside of the balloons where sunlight could warm them, giving rise to spurious temperature readings that were a degree or two higher on sunny days. Once this was corrected, though, the rise in atmospheric temperature matched those of land and water.
Are CO2 Levels Actually Rising?

Of this there can be no doubt. Recently reported analyses of Antarctic ice cores have revealed that present-day CO2 levels are much higher than at any other time during at least the past 600,000 years, in keeping with measurements made using ice cores from other locations.

Other evidence of global warming are the melting of glaciers and snow caps around the world, together with the melting of polar ice caps. The snows will be gone from Kilimanjaro within twenty years. Spring is arriving earlier and fall is showing up later in most parts of the world. Also, the animal kingdom is responding with migrations toward the poles.
Skeptics and Scoffers

There is probably a Gaussian distribution of opinions about any given topic. This was certainly the case with the relationship between smoking and lung cancer, and the relationship between diet and coronary artery disease. Personality factors enter into peoples' opinions, and often steer their arguments and opinions

One of the arguments is that global warming is a natural phenomenon that just happens to coincide with our wholesale burning of fossil, with a warming profile that just happens to match the rate of rise of global carbon dioxide and global temperatures.

Another scenario has been that global warming is attributable to volcanic effluences, arguing that human activities couldn't affect the global environment on such a perceptible scale. But human activities have caused acid rain, threats to wildlife, and the partial destruction of the ozone layer. Volcanic emission of CO2 is blamed for a few percent of the CO2 released each year, but there's been no long-term increase in volcanism over the past two centuries, nor have there been changes that would match the observed profile of CO2 enrichment.

A third notion is that the Sun's output has increased over the past century, or that the Earth has been exiting an interstellar  dust cloud over the past century.
Occam's Razor and Pascal's Wager

At some point, we have to withdraw to the most probable interpretation rather than honor equally all possible interpretations. We also have to inquire after the risk/reward ratios of different responses.
If climatologists are correct about the thesis that the burning of fossil fuels drives global warming, we'll be well-advised to speed up our transition to renewable power sources... solar, wind, geothermal, biofuels... or to nuclear power. In other words, we'll be encouraged to do what we need to do anyway, only sooner. It really comes down to cost. (I've read a forecast that by 2010, solar-electric power will be cost-competitive in many markets with grid-derived power.)

If we assume that the burning of fossil fuels isn't causing global warming when it is, then humanity and most of the animal kingdom may be wiped out.  I can't think of a single good reason to burn up all our fossil fuel so that a few ultra-rich people and corporations can get richer (even though I own stock in some of those corporations) when we have, or can rapidly develop and install, renewable energy equipment. And the cost of assuming it isn't happening if it is, is horrific.

Another factor in this equation is petro-politics. The next source of U. S. oil is apt to be Africa, with all the political vulnerabilities that this implies.

One of President Bush' first official acts in the spring of 2001 was to cut the federal solar energy budget in half almost halfway through the fiscal year! As anyone who has dealt with the federal government is aware, part of an agency's budget has already been spent by February. The effect on the federal solar energy program must have been devastating. (I didn't know then that our President, our Vice-President, and our current Secretary of State were oil-company executives before they took office.)

President Bush has argued that it's too costly to U. S.-based corporations (in the richest country on Earth) to embrace alternative energy solutions. I should think that the alternative is costlier ("Lead, follow, or get out of the way"), and a number of U. S.-based corporations are trying to compete as global purveyors of alternative power equipment. General Electric, Evergreen Solar, and Daystar Technologies are among the U. S.-based companies that are marketing state-of-the-art alternative-energy equipment. The alternative is to be left waiting at the switch as the world stampedes toward alternate energy purchases.

Other Warming Influences

Sound alarming? It gets worse. Ice and snow have a high albedo (are highly reflective). As ice and snow are replaced with bare soil or open water, more of the sun's heat may be absorbed, thereby increasing the rate of global warming.

There are strong indications that the Gulf Stream is beginning to shut down (declining 30% in the past 12 years), making cold regions colder and hot regions hotter (http://www.guardian.co.uk/science/story/0,3605,1654803,00.html?gusrc=rss). A complete shutdown would lead to a 4º C to 6º C (7º F to 11º F) decline in UK temperatures within 20 years. This, in turn, would greatly increase the incidence of snow and ice in Europe.

Compensating Effects That Might Brake Global Warming

The only agency that keeps the Earth's atmosphere from reverting to carbon dioxide like Mars and Venus is the fact that we have plant life that is very effective at converting carbon dioxide back into oxygen. The argument has been made that higher concentrations of carbon dioxide in the atmosphere will stimulate plants to remove carbon dioxide faster, and to produce more oxygen. But that applies only if plant fecundity is limited by the amount of atmospheric CO2. Plants also need water, fertile soil, and sunlight. (The presence or absence of wind might be as important in altering local carbon dioxide levels as the concentration of CO2 in the atmosphere.)

It might be argued that global warming will increase the Earth's cloud cover, thereby increasing the Earth's albedo, but an increase in cloud cover would also lead to a reduction in photosynthesis.

The sectors that have sagged are Financials and Housing, because of rising interest rates, and energy for the past few weeks because of falling oil prices.  However, if interest rates stabilize early next year, these sectors might take off again as post-hurricane rebuilding occurs. Also, long-term, industrial materials and energy are expected to rebound as China and India continue to expand.

First, we can boost solar energy research into organic photovoltaic materials to try to boost their efficiencies and lifetimes. We can also explore cheaper ways of constructing existing solar cells and their ancillary equipment and mountings.

Second, U. S. industry can outsource solar cell production to Asia to avail themselves (if they haven't already done so) of  lower labor costs, as well as encouraging their own installations of alternative power generation systems.

Third, we can fund research into battery improvements. There is the prospect of upping lithium ion battery performance from its current 50 watt-hours per pound to the point (100- to 150-watt-hours per pound) where it might become a serious contender for transportation, as well as storing energy generated by solar power and wind power generators. Chromium-based batteries (affording 200- to 300-watt-hours per pound), if they can ever be realized in a cost-effective manner, would have the potential to replace internal combustion engines.

Fourth, the government could purchase and install alternative energy equipment on government buildings, thereby boosting production levels and lowering costs of alternative energy generation subsystems.

Fifth, the government could tighten fuel economy standards for automotive manufacturers.

Sixth, the government could emphasize energy conservation. We could probably meet the energy savings goals set forth in the Kyoto Treaty virtually immediately by simply replacing our incandescent lamps with fluorescents, adding insulation to our houses, and replacing our appliances with more energy-efficient models.

The last president to lead us toward energy independence was Jimmy Carter... a nuclear engineer with a 170 IQ. Restoring the kinds of energy-independence tax incentives that his administration provided would be, I should think, a step in the right direction.

The current 2006 choke point for solar power expansion lies in the world's industrial capacity to produce polycrystalline silicon.