Category: Environment

The critics of the science of global climate change act as if climatology and the science if global climate change are somehow complicated, obscure, or esoteric. They also act as if it is a new-fangled theory, dreamed up by modern day Luddites. Both are simply not true.

The science of climate change is very basic, very simple. Most people have personal experience with the underlying science behind “global warming.” Most of us have done a simple science experiment, probably in High School, where we added salt into water and noted that it changes the freezing point. The basic idea is that an impurity in a solution changes the physical properties of the solution. Adding salt to water changes the freezing point.

Air is a gaseous solution of nitrogen, oxygen, argon and some trace elements. There is also gaseous – or vaporous – water in the air. Changes in these elements, or in other impurities in the air, change the physical properties of the air, particularly its ability to retain heat.

Believe it or not, must people have first-hand experience with this phenomena. Humidity, which is the measure of water vapor in air, changes the ability of air to retain heat. Most everyone knows this. The humidity in the air is why it typically stays warm at night in the summer. If, for example, it gets up to 86 degrees on a humid summer day, it might only cool off to the low 70’s at night. But if it gets up to the same 86 degrees on an early fall day, a day with low humidity, it may cool off into the 50’s at night. Anyone who has spent time in the desert has also experienced this effect. It may get into the 90’s or 100’s during the day, but it often cools down into the 40’s and 50’s at night. Places in the tropics, where the humidity is high, may also reach the upper 90’s during the day, but only cool into the low 80’s at night. The reason is that the water vapor in the air helps the air retain heat, or in the case of the desert, the lack of moisture in the air allows the air to cool quickly once the sun is down.

This is part of what is known as the greenhouse effect. The idea was first developed by the French scientist Joseph Fourier in the 1820’s. A British scientist named John Tyndall did studies in the 1850’s that helped explain why water vapor in the atmosphere held heat. He also said that other impurities in the air, including carbon, could help the atmosphere retain heat. Finally a Swedish named Svante Arrhenius put it all together in what is now known as the “Greenhouse effect”. There are two components. One component is that the impurities in the air alter the heat retention properties of the air, and the other component is that the impurities in the air alter the ability of the atmosphere to block infrared radiation emanating from the planet. So humidity allows the air to retain heat. Arrhenius did his work in the later early 1900’s.

Arrhenius also noted that increases in carbon dioxide in the atmosphere would cause the atmosphere to retain heat. Arrhenius actually thought that heating the atmosphere would be a good thing, and would help prevent a new ice age which might destabilize humanity. In a book called “Worlds in the Making” published in English in 1908 he said that if “the quantity of carbonic acid [CO2] in the air should sink to one-half its present percentage, the temperature would fall by about 4°; a diminution to one-quarter would reduce the temperature by 8°. On the other hand, any doubling of the percentage of carbon dioxide in the air would raise the temperature of the earth’s surface by 4°; and if the carbon dioxide were increased fourfold, the temperature would rise by 8°.” (p53) [See, e.g. the American Institute of Physics, which has an excellent history of the science behind Global Climate Change at: http://www.aip.org/history/climate/index.htm]

His numbers were off for a number of reasons, including the ability of the oceans to absorb carbon dioxide, but his description of the basic science of global warming, or climate change, was dead on. Raising the amount of carbon dioxide (and other carbon based impurities) in the atmosphere alters the ability of the atmosphere to retain heat and causes the atmosphere, and the planet as a whole, to heat up.

This has been the dominant model of climatology ever since (with a brief foray into global cooling, as discussed below). So we have known for well over 100 years that adding carbon to the atmosphere would warm the planet. The terminology changed recently because it was clear that the impact was not simply warming. The additional heat in the atmosphere manifests itself in disruption of normal weather patterns, and can result, as it did the past winter, in unusually cold temperatures in some regions. So now we use the more accurate terminology of “climate change” but the scientific principles remain the same. They are simple, and well established scientific principles, and they are principles that have been around for over 100 years.

Conservatives like to point out that in the 1970’s there was supposedly a great deal of concern about “global cooling” and the possibility of a new ice age. They like to refer to this to imply that scientists are a bunch of idiots and frequently get things wrong. The implication is that if they were so off base in the 1960’s regarding the possibility of “global cooling,” they’re most likely off-base now with claims of global warming. It’s a nice argument but is completely untrue.

Here’s the basic story of “global cooling.” My details are taken largely from a paper published by the American Meteorological Society called The Myth of the 1970’s Global Cooling Scientific Consensus, which is available at: http://journals.ametsoc.org/doi/pdf/10.1175/2008BAMS2370.1]

As noted previously, scientists have understood since the 1890’s that adding carbon based gases, particularly carbon dioxide or CO2, to the atmosphere would lead to increased atmospheric temperatures.

But in the 1950’s and 1960’s the amount of smog and visible pollutants (known as aerosols) were becoming a major concern. Some scientists suggested that the amount of pollution could block solar ration and potentially lead to the cooling of the planet. Just as a day is cooler when it is cloudy than when it is sunny because the clouds block the solar radiation, perhaps smog would have the same effect.

In the late 1960’s a few scientists published articles in peer reviewed journals and gave talks at climatology meetings presenting these ideas. But this was, based on an analysis in the AMS paper, a distinctly minority view.

Unfortunately the story was picked up by the “main stream media” and Newsweek published a story in 1975 called “The Cooling World.” The New York Times also published two articles discussing the possibility of global cooling. The Times, unlike Newsweek, did note that this was far from a consensus view on the impact of pollution on the environment. In fact, as noted above, it was the decidedly minority view. There is a chart on page 9 of the paper (Fig 1, pg. 1333 of the original Journal article) that shows the number of papers on global warming versus papers on the possibility of cooling in the peer reviewed journals. There was one article discussing the possibilities of global cooling in 1967, two in 1971, and one in ’74. ‘76, and ’77. In contrast, there was 1 warming article in ’65, ’67, ‘69 and 1971. There were two in 1970, 4 in ’71, 3 in ’74, 7 in both ’75 and ’77, 4 in ’76, 8 in ’78 and 5 in 1979. All total for the period, there were 7 cooling articles, 44 warming articles, and 20 that discussed issues of climate change but were neutral as to whether the overall climate may warm or cool.

Climatologist debated the issue, analyzed the data, and found it lacking. The “debate” over “global cooling” in the late 1960’s and early 1970’s took place in scientific journals, and shows how science works. An idea is proposed, and then it is analyzed and written about in journals. If facts support the idea it becomes consensus science. If facts don’t support it, it gets dropped. This is precisely what happened with the scientific discussion of global “cooling.”

Global cooling was proposed in the mid-1960’s as a plausible idea, but climatologists and other scientists analyst the information and determined that it was incorrect. The idea was dropped by climate scientists. Unfortunately the fact that the debate, or actually only part of the debate, became public, gave the general public the sense that there was disagreement or discord in the science. Nothing could be further from the truth. The “debate” over the possibility of global cooling shows that science works.

The modern world is the world of science getting it right. Computers and cell phones are dependent upon silicon computer chips that are the product of advanced materials sciences that rely, in part on the teachings of quantum mechanics to explain how electrons are transmitted within the chips. Modern communication technology, including cell phones, the internet, wireless communications, and data transmission satellites are all the product of modern science, including esoteric number theories, quantum mechanics, and advanced astronomy and cosmology that allow the precise positioning of geosynchronous communication satellites. It all works because science got it right.

We live increasingly long and healthy lives because of scientific advances in medicine, which are dependent upon modern understanding of biology, which is largely dependent upon understanding how genes operate and interact, and all of this is dependent upon the process of evolution. We live long and healthy lives, we benefit from many marvels of modern medicine, because science gets it right.
Every time a person uses a cell phone, logs onto the internet, uses GPS to determine their location or get directions, or benefits from modern medicine, they are essentially endorsing the modern world of science. They may not realize it, they may even doubt the science, but the reality is that modern technology works because science got it right.

I’m baffled then when I hear people, particularly intelligent people with advanced degrees, question the science of climate change. The science of climate change is based upon the same scientific principles, theories, methods and protocols that make computer chips work, that allow cell phones to make a call, that send rockets with rovers to Mars, that create disease resistant crops, and that eradicated diseases and improved health around the world.

How have all of these scientific advances worked, when somehow science gets it wrong regarding climate change?

The scientific principles underlying climate change are extraordinarily simple. No quantum mechanics, no warping of the space time continuum. The scientific theories underlying climate change has been around for well over a century, and in that time has been tested and confirmed. Like it or not, we live in the world of science getting it right. And that applies to climate change.