Global Warming Questioned by British Documentary

A week or two ago, a new documentary called “The Great Global Warming Swindle” was brought to my attention on a friend’s blog. While I haven’t seen the documentary, an article written about the documentary by Thomas Sowell contains enough inaccurate statements to make me question the validity of the documentary it references. I have taken a number of meteorology classes. Much of meteorology focuses on radiation, which also happens to be the root of the entire global warming issue. (Global warming is just the earth and it’s atmosphere absorbing more radiative energy than it emits.) I’ve picked out a few choice quotes from the article, and debunk them below.

There is no question that the globe is warming but it has warmed and cooled before, and is not as warm today as it was some centuries ago, before there were any automobiles and before there was as much burning of fossil fuels as today.

This statement is simply incorrect. While it is true that the globe’s temperature varies over the course of thousands of years as a result of Milankovitch cycles and other causes, there has not been any time in the past 650,000 years when the global average temperature has been higher than it is today. What the author is most likely referring to is the Medieval Warm Period (800-1300 AD). During this time, the average temperature was higher than normal in the European region and perhaps part of northern Asia. However, when you compare the average global temperature of both the Medieval times and current day, the average temperature today is much higher than it was back in Medieval times.

According to these climate scientists, human activities have very little effect on the climate, compared to many other factors, from volcanoes to clouds.

According to the IPCC report released earlier this year (page 4), human activities have a higher effect on global climate than natural sources. Furthermore, natural sources such as volcanoes and clouds actually cool the earth rather than warm it.

Clouds both cool and warm the atmosphere. Low clouds like a thunderstorm or thick layer of uniform stratus clouds cool the earth quite a bit, and reflect radiation from the sun back into space. High clouds, like the thin haze-like cirrus will trap some of the radiation the earth is emitting and warm the atmosphere slightly. The prevalence of low and mid level clouds wins out here with a cooling effect.

As for volcanoes, eruptions do release ash and greenhouse gasses up into the stratosphere and this has been measurable after relatively recent eruptions like Mount St. Helens. Since volcanic eruptions are relatively rare, their contribution to global climate is minimal to the extent that I’m not sure why the article or the documentary even brought up the issue. Usually, the ash dominates by blocking solar radiation for a net cooling effect, and after an eruption locations nearby would notice solar dimming.

While the effects of clouds and volcanoes combined will cool the earth’s climate significantly, CO2 and methane from anthropogenic sources have an even larger warming effect. Furthermore, the article brings up these two sources as if they are causing global warming instead of humans, when in fact they are acting as a negative feedback to the damage humans are causing.

These climate scientists likewise debunk the mathematical models that have been used to hype global warming hysteria, even though hard evidence stretching back over centuries contradicts these models.

I’m not sure what “hard evidence” the author is referring to, but there are several climate models developed at various universities and scientific institutions worldwide. Most of these models are tested from 1960 on forward, because we have solid temperature measurements worldwide during this time period. All of the best models match the warming that actually occurred during this time frame, and this reinforces the validity of these models. Again, I refer to the IPCC report (page 11) that shows output from up to 14 different climate models matching temperatures over the past 100 years only when they include anthropogenic forcing as opposed to just including natural climate forcing.

What is even scarier than seeing how easily the public, the media, and the politicians have been manipulated and stampeded, is discovering how much effort has been put into silencing scientists who dare to say that the emperor has no clothes.

Hmm…I’ve actually read several news articles reporting the contrary: the government often censors scientific reports written that support the global warming problem.

Academics who jump on the global warming bandwagon are far more likely to get big research grants than those who express doubts — and research is the lifeblood of an academic career at leading universities.

Actually, these grants can be used as leverage by the government to silence scientists. Release your findings, we pull your funding. Most researchers choose a topic they are interested in exploring, rather than focus on topics that have grant money available. Grant money is available through the NSF for a multitude of scientific topics.

Furthermore, this assumption of researchers “going after all the money” for selfish reasons is only valid if the researchers themselves got to keep most of the money. This is far from the case, and oftentimes researchers will only receive money directly from the grant if they buy their salary out from teaching classes at a university. Researchers still don’t get any increase in salary, they just won’t have to teach as many courses.

In politics, even conservative Republicans seem to have taken the view that, if you can’t lick ’em, join ’em. So have big corporations, which have joined the stampede.

While there is nothing I can say to completely disprove this statement, I can say that global CO2 emissions from businesses in the U.S. increase every year… If big corporations were jumping on the global warming bandwagon, wouldn’t emissions decrease?

Furthermore, why is global warming a political issue? It’s known that the earth is getting warmer, and it is also known that if there are lower CO2 concentrations in the atmosphere, the earth wouldn’t be as warm (this has been scientifically proven, by simply looking at the chemical makeup of CO2 and how it reacts to different wavelengths of radiation)… Wouldn’t the logical next step be to try and reduce CO2 concentrations in the atmosphere to return temperatures to around normal? I don’t see this as a liberal vs. conservative issue.

The difference is that we have the hardest and most painful evidence that there was a Holocaust. But, for the global warming scenario that is causing such hysteria, we have only a movie made by a politician and mathematical models whose results change drastically when you change a few of the arbitrarily selected variables.

Actually, I think we have much more information about global warming than just models and a movie. Google Scholar shows about 152,000 articles on global warming…

As for the “arbitrarily” selected variables, I would hardly call them arbitrary. I haven’t researched any one climate model so deeply that I would know how it works, but if the variables are anything like the hundreds of specified conditions used in meteorological forecast models, I would imagine they are comprehensive. Modeling is difficult, and at this point we just aren’t sure how some variables will change as the temperature increases. However, this only brings the models’ accuracy into question 100 years from now, and does not discredit the fact that the earth is warming because of anthropogenic forcing right now. From page 11 of the IPCC report, you can see that the model output matched the actual temperature much more closely when anthropogenic variables were taken into account. This alone is pretty significant evidence that the human race is effecting the earth’s climate beyond the natural environmental variations.

If you want to run a climate model on your own computer and learn more about what is involved, check out EdGCM.

If you would like to read more about the issues brought up in this documentary, here is a very lengthy discussion over on RealClimate.org (529 comments on the posting at this time). Large universal topics like this deserve to be debated. Fortunately, scientists have already discussed the issue extensively over the past couple of decades. Governments, corporations, and to some extent the media don’t like what has been discovered and are deciding to take issue with it. Unfortunately, this just delays actually doing anything to help the environment and return things to the way they were.