This is my answer from another question, but I copied it for here:
This is crazy. That colorless, odorless, tasteless, non-toxic gas called carbon dioxide is not a pollutant. It is a trace gas in the atmosphere. It underpins all life on Earth. It is plant food. All plants require CO2 for photosynthesis, and plants (especially photosynthetic micro-organisms) are the pillare supporting all life on Earth. The slight increase in CO2 over the last 35 years from 325 ppmv to 385 ppmv has increased grain yields.
It is really disturbing that you use the term "denier". A scientific consensus does not equate scientific fact. Consensus is a political term, NOT a scientific term. Just as "belief" is a religious term and not scientific.
You know what drives me nuts? Almost every time a global warming story is featured on television, there is a background image of a cooling tower on a coal-fired power station. The visible plume is not CO2, it is H2O. The plume of minute water droplets is the visual stimulus to support the popular view that CO2 is a pollutant of human origin.
When governments can change the galactic path of the Solar System, the variable energy emitted by the Sun, change cosmic ray flux, the wobbles in the Earth's orbit, the behaviour of bacteria and plate tectonics and ocean currents, then I will be convinced that they can change the climate.
I wonder if you can explain why the planet was warmer than today in the Medieval, Roman and Minoan warming periods, and there was no form of industry?
Or even look to today, we have been cooling since 1998. The computer models did not predict that. They said that after 1998 the planet would keep warming indefinatley.
So to the Anthropogenic Global Warming "believers", they have created a religion where logic, questioning or contrary data are not permitted.
Let me ask you this. What information would you need to reverse your stance on the theory of manmade global warming? Think about it. If you have no answer, then you are akin to an irrational, fanatical belief in an ascientific theory rooted in miscalculations and incomplete data.
Jonathan Swift once said "it is useless to attempt to reason a man out of a thing he never reasoned into".
Life has been very hard in cold times, war, famine, disease, poverty, struggle to survive. More people die in winter than in summer, there is more depopulation in global cooling events than in global warming events, and yet we are the first generation on planet Earth to fear warmth.
Source(s):
My Brain, Heaven & Earth by Prof. Ian Plimer