Wednesday, May 30, 2012

The trouble with carbon

In this series we’ve been analyzing a scholarly paper, “Solutions for a Cultivated Planet,” published Oct. 20, 2011 in the journal Nature. Lead author Jonathan A. Foley and his 20 co-authors argue that agriculture is destroying the planet through land clearing, pollution, and the generation of greenhouse gases, and will be unable in the future to feed a growing human population. The work published by Foley et al. is probably well intentioned, but the conclusions drawn are off the mark, relying as they do on a series flawed albeit popular and politically correct assumptions.

In reading the paper, one quickly realizes that far from offering workable solutions to the problems alleged, they champion a vague political approach, short on concrete ideas and long on the generality that “someone” should take care of things. While they don’t identify any specific person or institution, it seems clear they are advocating for some type of world authority to take charge of agriculture. As we pointed out in the initial installment of this series, all previous centralized approaches to agricultural production have failed miserably at the cost of millions of lives.

This time we’ll look at the problem Foley et al. see in agricultural production of “greenhouse gases,” particularly carbon dioxide (CO2) and methane (CH4), and usually lumped under the general category of “carbon.”

Foley et al. point to agriculture as the producer of  12 percent of anthropogenic (man-made) greenhouse gas production.

Before we delve more deeply into greenhouse gases, we’ll first put that number in perspective (which Foley et al. do not). All greenhouse gases, including the most abundant, water vapor, make up 2 percent of the Earth’s atmosphere. The rest is nitrogen, oxygen, and trace gases. CO2 and CH4 make up a bit more than 3.62 percent (3.62 percent CO2, 0.0017 percent CH4, a total of 3.6217 percent) of all greenhouse gases. Agriculture accounts for 12 percent of this total, or about 0.000086921 percent of the atmosphere – round it up and make it 9/100,000 (nine one-hundred-thousandths) of one percent of the atmosphere, or about 90 parts per million.

This is a small number. But small numbers can be important, so let’s look at the argument about the significance of man made greenhouse gases.

Greenhouse gases trap heat in the atmosphere, helping to keep the surface and the troposphere (the lowest level of the atmosphere) at an overall average temperature of about 15 C (59 F.).  As the popular argument goes (used by Foley et al. and thousands of others), the atmosphere was in a delicate balance before man started producing greenhouse gases during the industrial revolution by burning first coal, then oil. These added gases will reach a “tipping” point when the carbon dioxide level reaches about 400 parts per million (ppm). The present level is around 380 ppm. Once the tipping point is reached, the atmosphere could become a runaway greenhouse, sending temperatures soaring out of control, melting the ice caps, raising the sea level, and then boiling the seas away. All life on the planet would come to an end. With today’s atmosphere only 20 parts per million away from the tipping point, and agriculture already producing 90 parts per million of carbon dioxide, how much longer can man continue to grow food for a growing population before global warming destroys life?

This was a very, very scary question for most people in the late 1980’s and into the early 2000’s, when a small but vocal group of politicians, self-appointed experts, and an agenda-driven media began sounding the alarm. Prompted by the summary report of the U.N. Intergovernmental Panel on Climate Change (I.P.C.C.), Governments around the globe began spending billions of dollars to reduce man-made CO2 emissions. The U.S. Environmental Protection Agency (EPA) even labeled CO2 as a pollutant. Ethanol was touted as a safe alternative to gasoline, even though it actually releases more CO2 into the air than gasoline. A former Vice-President of the United States produced a very popular movie and declared the science settled and the debate closed. There was even a decade-long flirtation with carbon sequestration and carbon credit trading on the Chicago Climate Exchange.

But there were a couple of problems with story, regardless of how popular it was (and unfortunately, it remains popular to this day).

Firstly, a group of 43 paleoclimatologists (scientists who study past climate) began fiddling with the data they used in their climate models. After discarding some data which countered their carbon-driven warming hypothesis, and then emphasizing or adding weight to data which supported their hypothesis, they produced a now-famous “hockey stick” graph which showed two things: global temperatures began rising rapidly with the onset of the industrial revolution in the 18th century while CO2 levels were also rising. The researchers asserted that the correlation of warming and elevated CO2 proved causation; that is, carbon was driving warming. This is the conclusion they reported to the I.P.C.C.

Unfortunately, to produce this hockey stick graph, they had to delete the Medieval Warm Period (MWP, 900 A.D. to 1,300 A.D.) and the Little Ice Age (LIA, 1,300 to 1,850). Curiously, both the MWP and the LIA were present in the 1996 I.P.C.C. report while the hockey stick was absent. In the 2001 report the MWP and LIA were gone, but the hockey stick was there. Statisticians and other scientists caught on to the deception, and the 43 paleoclimatologists were severely taken to task. Later, through the “climategate” scandal, the group was found to have actively hidden and destroyed data, refused to work with other scientists, and attempted to have publication of papers countering their theory quashed. Not very scientific behavior at all.

Secondly, the Earth began cooling in about 1998, despite the fact that man-made greenhouse gas emissions were rising. Though some countries, like those in North America and Europe were attempting to curtail their emissions, other countries like China and India were producing much more as they grew increasingly industrialized. Rather than decreasing man made greenhouse emissions, there was a small but significant net increase. At the same time, geological and biological processes continued to add CO2, CH4, and other greenhouse gases to the atmosphere at a faster rate than humans possibly could.

When the planet began to cool, and greenhouse gases continued to rise, the core group of paleoclimatologists, along with many politicians and the major media, did what Professor Ian Plimer, Australia’s best-known geologist and climatologist, called “moving the goalposts.” Instead of global warming, the threat was now climate change, but the culprit was still man made carbon.

Proponents of the catastrophic anthropogenic climate change theory hold that an ill-defined “something bad” is going to happen if carbon levels keep rising. Many in the major media and famous folks from all walks of life (including a former Vice president) now claim that increased atmospheric carbon is to blame for hurricanes, tornadoes, heat waves, cold snaps, sea-level rise and fall, earthquakes, tsunamis, floods, droughts, and all manner of weather related and non-weather related phenomena.
Unfortunately for the proponents of this theory, there’s no evidence to bear this out, and plenty of evidence to refute it.

Although science has a very long way to go in understanding climate, the main climate drivers are well known. They include the sun, perturbations in the Earth’s orbit around the sun, cosmic rays, geological processes here on Earth such as plate tectonics, volcanoes and earthquakes, cloud cover, and cloud formation.

In general, the sun heats the planet to an average of about 15 C (59F.). Part of the sunshine, or electromagnetic radiation, which strikes the Earth is immediately reflected back to space by clouds and ice, and to a lesser extent, by land and water. Part of the energy warms the land and the oceans, and some of this warmth, or heat, is radiated back toward space as infrared radiation. Temperature differentials in the oceans cause currents, which move warm water from the equator toward the high latitudes, where it cools and flows back toward the equator. The warming land and oceans also transfer heat to the air, causing air currents to do essentially the same thing.

Critically, though, CO2 and CH4 are able to hold and slowly re-radiate infrared radiation in the 14-16.5 micron band. Without this slow release of collected warmth from the atmosphere’s greenhouse gases, the planet’s average temperature would be about –3 C (26.6 F., below the freezing point of water). At present CO2 and CH4 levels, these two gases capture and re-radiate nearly all the infrared energy radiated from the surface in these wavelengths. Even doubling CO2/CH4 levels to around 800 ppm would capture only a tiny bit more, perhaps enough to cause a 0.5 C increase in global temperature.

All greenhouse gases reradiate infrared radiation toward the surface, which serves to hold, but not increase, heat. They also reradiate much more heat away from the surface and toward space. The narrow wavelength band captured and reradiated by CO2 and CH4 is only a fraction of the heat radiated from surface, however. Much more heat (in the 7.5-14 and 16.5+ micron bands) is radiated and transported by atmospheric convection high into the atmosphere where it is radiated to space. Far from acting as atmospheric warming agents, greenhouse gases are actually part of a planetary cooling system. If the Earth had no water, which provides a feedback loop in the warming/cooling cycle and atmospheric turnover, there would indeed be runaway warming on Earth, just as there is on Venus, which does lack water.

Leaving aside CO2’s effect on the atmosphere, which is indeed important but certainly not a climate driver, CO2 is vital for life as we know it to exist on this planet. All plants need CO2 for photosynthesis, the process in which plants take energy from the sun and combine CO2, water and nutrients to grow. If plants had no CO2 to “breathe,” they would fare no better than an animal without oxygen. In fact, the oxygen we animals cannot do without is released by plants as a waste product of photosynthesis, and plants use the CO2 we release as metabolic waste when we exhale.

One final problem with carbon for this installment. The climate alarmists have taken to attacking carbon when they really mean CO2. Perhaps it’s a trivial complaint, particularly when this crowd has rarely, if ever, said clearly what they mean.

Nevertheless, carbon is absolutely essential to life as we know it. Carbon is the scaffolding for the other molecules that make up living organisms. Carbon is the backbone of life, providing the critical linkages in cells, tissues, proteins, amino acids, sugars, starch – and the list goes on.

There’s nothing wrong, and everything right, with being concerned about the ecology of our planet. Earth is the only home we have. Unfortunately, and sadly, a lot of people have seen fit to play fast and loose with the rules of science and journalism, and to gain in money or prestige while preying on the fears of their fellow human beings. And while doing so, they make a mockery of the fascinating and wonderful world we inhabit.
So the next time someone tells you that you, or someone else (the accuser seldom feels responsible in any way), is destroying the planet with carbon, be a little skeptical and look at the world the way it really is, and not as they tell you it is.

Next time: Media bias, and why you seldom get the whole story.

No comments:

Post a Comment