There are many theories, some of which are not convincing and some of which point out the difference in degree of the progress of global warming; in summary, any of them does not show a scientific ground for denying the influence of global warning caused by greenhouse gases originated from fossil fuel.
反証可能性に至っていないもの、地球温暖化の進行程度の差を指摘するものなどが多く見られ、いずれの場合も化石燃料由来温室効果ガスの地球温暖化効果自体を否定する科学的根拠が示されているわけではない。