Some Facts about Global Warming

Last night I was flipping through radio channels and I paused to hear a political pundit going on about how there is no global warming, and that it’s all a lie to keep us afraid and to make money for the Liberal Green Machine. His sole piece of evidence for his claim was that it snowed in New Orleans. I nearly fell out of my seat. Here is a well known radio personality, formerly a politician and an FBI agent, presumably an intelligent person, and he’s spreading this idea based on a single point of data that shows an abysmal lack of understanding of the scientific process in general and the phenomenon of climate change in particular.

I had thought that the debate over the existence of Global Warming had been decided. The data is in, the average temperature of our planet has gone up. The only thing that is still up for debate is whether or not the human race caused it. But with talking heads peddling their agendas, and they can be convincing or they wouldn’t be effective at their jobs, without the basic facts its hard to know whether to listen to the doomsayers or the naysayers. So, I’ve done a little research and gathered together some facts from neutral, reputable, scientific sources. What I found was interesting, and, while I expected some of it, I was completely surprised by other facts about what is going on with our planet.

The Scientific Method

A basic understanding of how science works is necessary to fully appreciate the weight of the evidence. It’s important to understand the steps scientists use to determine when their ideas have merit, and when they need to go back to the drawing board. Here are the basic steps involved:

  1. Observe a phenomenon.

  2. Formulate a Hypothesis to explain the phenomenon.

  3. Test the Hypothesis.

  4. If the data gathered supports the hypothesis you have a theory, if it does not, you must modify your hypothesis to incorporate the new data and test it again, go back to step 2 and repeat until the your hypothesis explains what has been observed.

  5. Once you have a theory that fits all the facts and it has been throughly tested it must be published for peer review so that other scientists can pick it apart, find flaws with it, point out where you are wrong, duplicate your experiments or re-evaluate your data, and generally put you through a rigorous process of defending your theory. If other scientists find any flaws with your theory, you must go back to step 2 and do it all over again.

  6. Repeat, ad infinitum. Anytime the observable data contradicts the theory the theory must be scrapped or modified. Theories that stand the test of time, after all this poking and prodding trying to prove them wrong, are generally considered reliable models.

So how long has the idea that CO2 and temperature are related been around?

The idea that CO2 in the air is an important determinant of global temperature is actually quite old, it was first theorized by Svante Arrhenius (1859-1927) in a paper published in Philosophical Magazine 41, 237-276 (1896)” [1]

So the basic theory of the Greenhouse Effect has been around since 1896 – over a hundred years – and it is still going strong. No evidence has been found to disprove the theory that the amount of CO2 in the atmosphere has a direct correlation to global temperature.

There is a caveat however – it is important to point out that correlation does not imply causality. In fact there is data to suggest that there is a lag, and temperature rise actually comes before a corresponding rise in CO2 [2]. So, just because a theory stands the test of time it does not mean that the implications of that theory are not up for debate. This is one small example of why there is so much contention about Global Warming.

Our Complicated Climate

Here is the crux of the matter – our climate is so complex that there is no one easy indicator or explanation. There are so many forces and variables that drive our weather that it is difficult to predict local weather more than about three days out with any degree of accuracy. But by taking thousands of data points from all over the globe spanning over a hundred years, we can see that temperatures have been rising [3]. In fact, temperatures, on average , have been increasing steadily over the past 40 years and are higher now than at any time in the past 2000 years [4].

Now, the reason I emphasize on average is this: just because some areas may experience an unusual cold snap or winter storm it does not mean that the Earth is not warming up. Greater warming means that weather patterns will shift in unaccustomed ways – not that the whole Earth will suddenly become as sunny and warm as Miami. More heat adds more instability to the climate, allowing for such things as wind-driven arctic fronts moving farther south faster than usual and causing snow in New Orleans. Or stronger hurricanes, or tornadoes in winter, or extended and more severe fire seasons driven by stronger and more frequent Santa Ana winds. But here’s the confusing part: just because global warming is one explanation for changes in our climate, it doesn’t mean it’s the only explanation, or that the extreme weather of the past few years is a direct result of temperature increases. The jury is still out, and scientists are still gathering data. But just because science isn’t certain what affect warming will have on us doesn’t change the facts – warming is happening.

There have been periods in distant prehistory when the Earth’s temperature was much higher than it is now [5], and those who argue against global warming love to point this out, but this argument is something of a red herring. The reason global warming is such an important topic is because it affects our lives today. We did not have cities teeming with millions of people during the Mid-Cretaceous Period. In fact, it would be better if it were a man made condition because we would then have a chance to reverse it. The earth, and life on it can, and will, survive a rise in temperatures, and humans are adaptable enough that our race will survive. But will our quality of life? Flooded cities, and the threat of drought and the loss of thousands of acres of viable farmland would have a very real impact on the survival of millions of people. So it is important to sort out the tangle of forces that impact our climate so we can plan for future changes – regardless of whether we caused them or they are natural occurrences.

The Sun

Gases in our atmosphere are not the only things that affect our planet’s temperature. The biggest influence is our source of heat – the Sun. The sun goes through 11 year cycles in which the number of sunspots ebb and flow. There is evidence that during periods of low sunspot activity the Earth receives less warmth from the sun – periods of almost no sunspot activity such as the Sporer, Maunder, and Dalton minimums seem to coincide with dips in global temperature [6]. It just so happens that we are in the midst of a sunspot minimum during 2008/2009 [7], which could account for a year or two of lower temperatures in the midst of a general warming trend.

So, while there is no doubt that Global Warming is real and is happening right now, there is debate about its causes and it’s results. Every day we have more data, and we move closer to answers, but currently we don’t have those answers. And if anyone tells you that they know, beyond a doubt, what the deal is with Global Warming, ask them to prove it, because we’d all like to know.


  1. Library 4 Science – Global Warming Greenhouse Science

  2. Science Bits – The Inconvenient Truth about the Ice Core Carbon Dioxide Temperature Correlation

  3. Met Office – Climate Change: fact 2

  4. NOAA/National Climactic Data Center – A Paleo Perspective on Global Warming –

  5. NOAA/National Climactic Data Center – A Paleo Perspective on Global Warming –

  6. Sunspots and Climate –

  7. NOAA – Solar Cycle Progression –