The first thing to be aware of is that the warming effect of carbon dioxide is strongly logarithmic. Of the 3 that carbon dioxide contributes to the greenhouse effect, the first 20 ppm has a greater effect than the following 400 ppm. By the time we get to the current level of 384 ppm, each 100 ppm increment will produce only about 0.1 of warming. With atmospheric carbon dioxide rising at about 2 ppm per annum, temperature will rise at 0.1 every 50 years for the next couple of hundred years before the effect becomes minuscule. The warming of the 20th century, as the Earth came out of the Little Ice Age, was a consequence of short, high-amplitude solar cycles. A number of solar physicists have predicted that the next solar cycle, Solar Cycle 24, will be quite weak. Based on the correlation between solar activity and the Earth's climate, a temperature decline of 2C is predicted for the mid-latitude regions over the coming decade, equating to the experience of the Dalton Minimum. Anthropogenic warming due to carbon dioxide will not ameliorate this temperature decline. Increased atmospheric carbon dioxide is wholly beneficial due to it's fertilisation effect. Efforts to inhibit Australian carbon dioxide emissions are exactly wrong in science._x000D_
FORMAL CITATION:Archibald, D, 2009. Climate change - relative solar and anthropogenic forcings, in Proceedings New Leaders' 2009, pp 67-70 (The Australasian Institute of Mining and Metallurgy: Melbourne).