In defence of AGW, this link argues that heat fluctuations from within the Earth are far too small to contribute to global warming.
http://www.skepticalscience.com/heatflow.html The interesting thing is that according to fig. 4 energy produced by fossil and nuclear sources is already 1/3 of the energy flow from within the Earth. If LENR can really replace all other energy sources and if the demand for energy grows a hundred times then the "holy grail of energy" could bring about a global heat pollution problem. Harry
