This climate science is pretty complex right? I mean, they say a butterfly flapping its wings can cause a chain of events that leads to a cyclone on the other side of the world. How then can we even begin to understand what the burning of fossil fuels is going to do to our climate? The answer isn’t entirely simple, it’s often made out to be a lot more complicated that it needs to be. Here’s how I see it.
CO2 Leads Heats The Surrounding Atmosphere More than Normal Air Does
There’s some complex physics behind this one, so let’s forget about the physics and just watch this experiment which displays it perfectly:
Absolutely a simplification of what’s happening on planet Earth, however, it does demonstrate a fact that even the most sceptical of people have to agree on, ALL ELSE BEING EQUAL, CO2 causes more heat gain in the atmosphere than normal air. There are many more similar videos of experiments on the internet simulating the same cause and effect. Myth busters even have one here. But how does this fact pan out in real life, how do we model what will actually happen to the atmosphere, or more importantly the entire planet, if we keep up our current rate of carbon pollution?
Predicting the Outcomes of our Greenhouse Gas Pollution
So how do we respond to this information? To do so in an informative manner we need to determine what the likely effect of greenhouse gas pollution will be. If the effect is negligible there’s nothing to worry about. The waters really get muddied here though because although we can calculate the warming effect of CO2 if all else is equal, all else isn’t equal. In fact, it’s very complex.
Nature responds to different concentrations of CO2 in the atmosphere in a variety of ways. Some of these responses reduce temperature (mitigating effects), some increase it further (amplifying effects). For example, the ocean uptakes CO2 as the levels increase in the atmosphere (it effectively becomes a little bit more acidic), a mitigating effect. However, conversely, as the oceans warm there is a risk that buried deposits of frozen clathrates will melt and cause large releases of methane (another greenhouse gas) into the atmosphere. There are probably thousands of these mitigating and amplifying effects and many of them we haven’t even thought of, can’t quantify or can’t predict when they will take effect.
This leads us to rely on empirical modelling. Basically, take a look at history and determine what the world was like with different levels of CO2. We can do this with modern day records and also pre-historically with ice cores and fossil records. They paint a pretty obvious picture, and that there is a very strong relationship between atmospheric CO2 levels and average surface temperatures around the globe. Check out the latest research on this here conducted by Berkeley University. This is a very interesting study, it is my understanding it was set up because of some perceived discrepancies in the accuracy of similar studies conducted earlier and it was thought by many that the results would likely discredit the former studies. Well, the results are out and they support the former studies entirely. Indeed the head of the study, physicist Richard Miller had this to say:
“Three years ago, I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming,” the physicist wrote in an op-ed piece published in the New York Times.
“Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.” (See article here)
Why is he now worried, this graph probably explains it quite well:
What the above graph shows is that we can very accurately predict temperature rises with CO2 increases in the atmosphere. So although we can’t be exactly sure of all the mechanisms (mitigating and amplifying) that are leading to a warmer climate due to CO2 increases, the evidence is extremely compelling that CO2 increases result in increased temperature.
More historical records support this theory. By measuring captured air from ice cores drilled from huge glaciers dating back thousands of years and matching this to fossil records to determine sea levels we also know that higher CO2 levels in the atmosphere corresponded to times of higher sea levels (warmer atmosphere, less ice at the poles). Once again, although we don’t know all the exact mechanisms that cause the warming, the evidence is compelling that CO2 increases result in increased temperature.
Our Part in Climate Change
Now think back to that last blog post I wrote on Australia’s energy use. Taking this information, in conjunction with the evidence above, we need to take personal responsibility for climate change. It is my responsibility, as well as yours, that we are changing the climate due to our huge thirst for cheap energy and consumer goods (which rely on cheap energy to manufacture). There is no point sitting back in a comfy arm chair pointing the finger at the coal fired power station and proclaiming “they are polluting our atmosphere!”. It just so happens that the factory that made the comfy arm chair needed the power from the power station (and your TV which is receiving the images of the terrible polluting coal fired power station, was also made with the help of coal, and relies on coal to work). We all need to start drawing these connections to truly understand our responsibility.
Once the connection is made, next step is determining our response. But in order to do that we really need to know what a warmer planet means, for example, if a warmer planet is better, then why worry? I’ll explain that in some details in my next blog post on this topic.
Check out the sources of the article here:
Global Warming in a Bottle: http://www.youtube.com/watch?v=Ge0jhYDcazY
Myth Busters: http://www.youtube.com/watch?v=pPRd5GT0v0I
Oceam acidification (mitigating effect): http://en.wikipedia.org/wiki/Ocean_acidification
Clethates release (amplifying effect): http://newscenter.lbl.gov/feature-stories/2011/05/04/methane-arctic/
Prehistoric Climate and CO2 Relationships (example study): http://atripati.bol.ucla.edu