The problem with many people (deniers) who have arguments on any issue is that they are not looking for facts to establish their own viewpoints. This becomes obvious when they, not content to say, “I strongly disagree with [idea] and believe [counter-idea],” but bluntly say, “[counter-idea]” and then proceed with that premise regardless of what anyone else says. Once that happens, those who reject the counter-idea find themselves becoming dogmatic in return to avoid appearing weak, thus degrading the general content of the discussion. The deniers rely on ingrained prejudices they know exist in many other people in order to build a following.
The opposition to evolution is entirely based on religious prejudices supported by semantic ploys, and nothing else. A lot of the “evidences” used to attack evolution are things that are exceptional in nature and when the Creationists see them, they say, “We do not know how these things could have happen, so we may safely assume that God did it.” That attitude totally denies scientific thinking. Evolution is scientific precisely because it is consistent with physical and chemical laws that were previously established via the scientific method. That Creationists do not note this obvious fact discredits them from the start.
As for the global warming issue, people have a natural tendency to deny facts that make them uncomfortable, because they know that then they will have to make great sacrifices to undo the damage that is being done and prevent more damage. The corporations and the politicians who support them play on this laziness to give excuses for not doing anything to change things. For example, the statement that increased solar output is a factor behind global warming only adds to the urgency that we keep the emissions of greenhouse gases at a low levels in the future; it does not negate our responsiblity to deal with the problem. That a few areas in the world are colder than normal is a result of warmer atmospheric conditions causing greater evaporation of water, resulting in greater cloud coverage and precipitation in areas that are prone to them, and of course this causes temperatures in those areas to fall. But the deniers forget one thing: The DESERT regions, which make nearly a third of the land area of Earth, are NOT affected by this trend and the temperatures there will remain high, resulting in great instabilities in the atmosphere, producing a greater frequency of storms.
Natural reality is complex, and science is supposed to measure that reality in all its forms. Those who attempt to reduce it to a simple formula via “logical” arguments are in fact the worst enemies of science.
Global warming deniers’ claims about a conspiracy driving the concern about global warming are a classic attempt to “turn reality upside down”. In fact, the real conspiracy is between the rich executives of the fossil fuel corporations and the conservative politicians whose servicies are paid for by the executives. Some scientists also side with the deniers, but that only indicates the extent of corruption that may exist in any profession, as well as the tendency of even people who should know better to decieve themselves.