Feb 9, 2016
I remember one Nova program several years ago saying that human produced about 1 watt of energy per square meter for all land area and that is contributing to global warming. It is obvious to me as a physicist to know that the program is seriously wrong. The two main factors for global temperature control is solar input and earth's radiation output. Green house gas (GHG) cause global warming because the radiation output with lowered emissivity need to radiate at higher temperature, therefore partially return to the original radiation energy level. The small difference that cannot be compensated is the stored thermal energy (heat) of global warming. With solar energy input at about 5000 times human generated energy and the fourth power radiation energy dependence, the slight increase in energy output can only cause less than 0.05 C temperature increase. Apparently, some people related to Nova program also noticed this mistake and the program withdraw from broadcasting shortly afterward. I know from this experience that Nova program is not completely trustworthy. I hope the producer would check with more knowledgeable people before the broadcasting. Global warming is real, but the prediction for disaster is far from proven. Having too many alarmist projecting distant future problem without clearly relating the realist time frame will erode Nova credibility.