Wednesday, 17 September 2014

Climate Change - part 2

 Update: Click here for parts 1, 3, 4

Welcome to part 2, I hope you enjoyed part 1 and understand I am not a fundamentalist climate scientists who is forcing stuff down your throat without some serious thought.

As I pointed out in the first post, everyone pretty much agree global warming is happening. As such I have included a graph below which demonstrates this. Similar graphs to this caused a lot of controversy by making the claim that there is a link between the rise in anthropogenic gases and climate change.

 (Source)
As you can see from this graph there has been a dramatic increase in carbon dioxide (CO2) and methane (CH4) over the past 150 years which coincides with the industrial revolution and mass manufacturing. From there it is easy to make the logical leap to say that the greenhouse effect is due to this increase in CO2 and CH4, as they are greenhouse gases which can in fact cause a greenhouse effect. This is even corroborated further by the research which shows that CO2 increase proceeds a temperatures rise, see image below. As such if we are to look at the current CO2 levels we are surely in for some serious heat in the not to near future.

For this reason I believe that the predicted rise attributed to anthropogenic gas emissions is completely reasonable. However, even if we are to dismiss this CO2 relation for a moment there is still reason to be concerned. This brings me to my first study (link is subscription)  which I really think proves that we should be worried.

This manuscript shows that an increase in CO2 in the atmosphere leads to an increase in the emission of NOx and CH4 gases from the soil i.e. bacteria in the soil. Basically what is happening is that plants are getting placed under stress by an increased CO2 concentration which leads to an unexpected result i.e. NOx and CH4 emissions from the soil bacteria. This is not what is expected and in fact points to the fact that the earth is not this ideal CO2 remover that everyone thought. It would have been if this CO2 adsorption by plants had not lead to this side effect, but this is not what is happeing.

This is not the first study that shows this type of link between increased CO2 in the atmosphere leading to increased other anthropogenic gas emissions, and it won't be the last, but its the one that caught my eye.  So why did this make me double take? This result is important  as CH4 is a far more potent greenhouse gas and usually we think that with an increased CO2 leads to more vegetation as plants absorb it. However, in this case it means even if plants are absorbing more CO2 and producing more leaves, thereby offsetting (slightly) the increase in CO2 in the atmosphere, this in turn leads to an increase in CH4 in the atmosphere.

This is just one study that makes me realize that the human contribution to climate change could in fact lead to dire consequences.