Calculating Global Warming
I have a background in Science and have studied Maths, Physics and Meteorology at University, so I suppose I should be qualified to make such a calculation.
Of course, I don't have millions of government money to spend on super-computers, however I feel if you can't prove Global Warming on a humble home PC and a bit of research, then we are left just trusting that the guys paid to wear white-coats know what they are talking about.
To give you a quick overview of my method, I have divided the atmosphere into ten equal layers (equal in weight). I have assumed a constant input of sunlight then calculated the energy balance from radiation and convection between the ten layers. The method requires some good data on how different Greenhouse gasses absorb different bands of infrared light.
Cutting to the chase, these are the results I got:
If I simulate an atmosphere of a pre-industrial world, I get a surface temperature 0.5 degrees less than current.
If I simulate an atmosphere with twice as much CO2 as today, I get a surface temperature 0.7 degrees warmer than today.
If I simulate an atmosphere with twice as much CO2, twice as much Methane and Nitrous Oxide, I get a surface temperature 1 degree warmer.
Here is the detailed result of my work:
Tenperature Results - Graph
Tenperature Results - Table
Note that there are some more significant warmings at heights associated with an air pressure of 350hPa - that is probably about 10-12 kilometres high I suppose. To understand the graph and table above - the temperatures are in Kelvins and 273 degrees Kelvin is roughly 0 degrees Celsius. A pressure of 1000 hPa is roughly the air pressure at the surface of the earth, so think of the vertical axis as being height from surface.
If you want to see all the modelling in its ugly technical glory, It is all here:
So, what does this all mean?
Firstly, it shows that with some data and a bit of programming know-how and understanding of physics, you can prove that the Anthropogenic theory of Global warming is true.
I am still a long way off from confirming the scary predicaments that the professional climate modellers are warning us of!
So, this hard-work has in many ways shifted me off the climate-skeptic position straight back onto the fence. Yes, humans are warming the earth - but probably not that much.
I have been thinking hard about what my model has missed, and this may be it. If one degree of warming can cause snows in the Northern Hemisphere to melt earlier then, perhaps the soils can absorb more sunlight and warm the planet further?
I really don't know? such feedbacks require a far more sophisticated modelling technique, but I doubt it is the difference between 1 degree and 10 degrees of warming!
Nevertheless, maybe 1 degree of warming is still significant in itself? we have already warmed the earth half a degree according to my model, and the way we go through fossil fuels at an exponentially increasing rate, who says we won't go past doubling the greenhouse gasses in the atmosphere?
Maybe my model says we still have plenty of time to act, but that is hardly a message to tell the world, who are trying to find excuses not to act even with the worst possible scenarios.