There are four pillars to global warming:
- The Earth has experienced unprecedented warming.
- Human activities, particularly the release of CO2, are the cause for this warming.
- The consequences of this warming are dire.
- We have to take immediate action in order to mitigate the damage.
1. No one argues that the Earth has warmed but is it unprecedented? Records are kept by a small number of researchers and they tend to be ideologues. The Climategate emails show that researchers have actively suppressed outside scrutiny. They have also used "tricks" on the data. Comments in the source code for a computer program used to collate multiple temperature records into a world-wide average show that the results cannot be reproduced. If there were errors in the original graphs there is no way to find them.
2. Graphs of warming do not match predictions. A lot of warming took place before heavy CO2 build-up. Warming in the last decade largely plateaued. There have been significant periods with no warming. Even the web site Real Climate published a paper speculating that the biggest warming during the 1980s and 1990s included natural cycles.
3. The real question about global warming is if it is beneficial, harmful, or benign? The most recent IPCC said in no uncertain terms that warming is harmful. They predicted that, among other things, it would deplete the source of most of India's drinking water and cause the loss of 40% of the rainforests. It turns out that these claims did not come from peer-reviewed sources. They came from advocacy papers from the WWF and Greenpeace and have been dis-proven. Worse, the head of the IPCC knew this and still took grant money to study these bogus effects. More than two dozen parts of the IPCC report have claims that are only supported by advocacy group position papers. These were inserted late in the review process. It is obvious that the original report was not scary enough and that the authors were encouraged to "punch it up" by salting it with worse-than-worst-case scenarios.
4. Why should we act immediately when we don't really know if it will be effective or if the alternative will be worse than the result of non-action?