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Eco-Justice Notes
The E-mail Commentary from Eco-Justice Ministries

Refresher Course
distributed 2/26/10 - ©2010

This week's issue of Eco-Justice Notes is underwritten by Reid Detchon of Bethesda, Maryland. His generous support helps make this publication possible.

The East coast of the United States has been hit by a series by record snowstorms recently, and quite a few prominent crackpots have used those weather events as an occasion to dismiss "global warming." (They of course don't mention the shortage of snow in Vancouver, and the disruption that dry ground has caused for the winter Olympics.)

The simplicity of "if it snows a lot, it can't be getting warmer" is at odds with the complexity of climate systems. Indeed, major snowstorms are entirely consistent with the physics of the greenhouse effect. But those who have used blizzards for denial are not attacking the science. They pay no attention to an established body of research with detailed models and reputable predictions -- because there is nothing there to attack. The science is rock solid. So, those who are opposed to the steps needed to bring healing to our planet resort to distortions and character attacks to discredit reputable scientists, politicians and other advocates.

Unfortunately, when the grandkids of a US Senator build an igloo on the Capitol grounds, and put up a sign calling it Al Gore's new home, that makes the news. It does not take much mocking or questioning to sow seeds of doubt and confusion in an easily distracted public -- a point made well in an excellent article by Bill McKibben this week.

Today, I want to offer a very brief refresher course on climate change. Let's go back to the very basics, and reaffirm the evidence for this matter of great concern.

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There are two things to keep in mind: (1) the well established science about the greenhouse effect, and (2) undisputed measurements about greenhouse gasses. Any discussion of climate issues that does not start with those two points is wrong.

It was only in the 1600s that the presence of different gasses in the atmosphere was discovered. Oxygen, hydrogen, nitrogen and carbon dioxide were identified as parts of the atmospheric mix. Simple experiments showed, for example, that a candle burning under a glass dome would go out after using up a small percentage of the total volume of air -- the oxygen -- because the remaining gasses don't support combustion. (I did the same experiment in a high school science class.) Carbon dioxide was identified as one of those gasses by Joseph Black in 1754.

British physicist John Tyndall is the one who, in the late 1850s, pointed to carbon dioxide as the gas that reflects infrared radiation and warms the planet, what we now refer to as the greenhouse effect. The essentials of what he described have been unquestioned for over 150 years. We now know that other trace gasses also have strong greenhouse properties. Methane is one of the most significant of those in today's climate crisis.

The greenhouse effect explains why Earth maintains a livable temperature -- our planet would be an ice ball without that warming influence. It explains why Venus is so hot, and accurately describes the temperatures of the atmosphere on Mars and on Saturn's giant moon Titan. No reputable scientist disputes the presence or the functioning of greenhouse gasses, on Earth or any other planet.

The human impacts on Earth's atmosphere were discerned not long after Tyndall's discovery. In 1896, Swedish chemist Svante Arrhenius published an article that stated, "We are evaporating our coal mines into the air." He concluded that adding so much carbon dioxide must be causing a warming effect with "a change in the transparency of the atmosphere."

Correction 10/6/10: I have been informed that this widely used quotation did not come from Arrhenius. The chemist did make very detailed calculations about human impacts on global temperatures from burning coal -- but he did not write about "evaporating our coal mines" or express concern about that warming.

It was obvious to those who thought about it that the amount of carbon dioxide in the atmosphere was increasing, but the scale of that increase was hard to document. The groundbreaking work on that front is attributed to Charles David Keeling, starting in the 1950s. In the mid 50s, Keeling measured CO2 levels of 315 parts per million in winds blowing off the Pacific Ocean, an good expression of the global average concentrations. Keeling's continuing research, from an observatory in Hawaii, are familiar in a now-familiar rising zig-zag graph. Carbon dioxide levels fluctuate by season, but edge up a bit every year, because "we are evaporating our coal mines", oil fields and forests into the air.

Countless researchers have added to Keeling's measurements. Into the 1990s, the levels of CO2 rose by about 1 part per million per year, and are now going up by 2 ppm. The current levels of CO2 are listed as 387 ppm -- 72 parts per million higher than what Keeling measured 55 years ago. That's a 23% increase.

Whenever I consider climate change, whenever I listen to debates about what is happening to our planet, I go back to these two central realities. (1) Greenhouse gasses warm a planet, with an effect that depends on the concentration of the gasses. (2) The concentration of carbon dioxide and other powerful greenhouse gasses has been increasing rapidly in Earth's atmosphere, especially because of human impacts through the last century. A multitude of measurements show that the planet is warming, just as the greenhouse theory predicts.

Unless somebody can provide a description of other factors at work, then we can have confidence that rising amounts of CO2 will translate fairly directly into rising temperatures. (Some atmospheric cooling factors have been described, and their relatively minor effects are part of the standard climate models.) As I often say, the burden of proof now falls on those who say that the planet is not warming. As far as I know, no scientist has provided a theory or model to show why the greenhouse effect is not shaping our planet.

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God's creation is an orderly, if very complex, place. There are rules that describe and define how things work on this planet, and across the universe. Things like the chemical composition of atmospheres and oceans can be described, and changes in those compositions have predictable effects.

On our little planet, our "Spaceship Earth", humans are now having a definite effect on those natural systems. Among other things, our burning of fossil fuels and wide-spread deforestation have increased the concentration of greenhouse gasses, and the planet is warming.

A few big snowstorms on the East Coast don't change that fact. A few injudicious emails between climate scientists doesn't change the indisputable truth of the core research.

The tactics of those who claim that a localized snowstorm disproves global warming are slimy and despicable -- and I lament that they are fairly effective in our sound-bite media world. An igloo with a sarcastic sign conveys an easy, simplistic and lying message.

In the face of those lies and misdirections, in the face of an increasingly disinterested public, we need to be persistent in naming the two most basic facts. The greenhouse effect is real. Increasing levels of carbon dioxide are strengthening that effect, and warming the planet.

Remember those two points. Repeat them often. Because, unless we hammer home those basic details, we will never make any headway in addressing the climate crisis.

Shalom!

Peter Sawtell
Executive Director
Eco-Justice Ministries

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