Climate change denial is a form of science denial characterized by rejecting, refusing to acknowledge, disputing, or fighting the extensive evidence for anthropogenic global warming that has led to a scientific consensus on climate change. Those promoting denial commonly use rhetorical tactics to give the appearance of a scientific controversy where none exists. Climate change denial includes raising unreasonable doubts about the extent to which climate change is caused by humans, its effects on nature and human society, and understating the costs of climate change adaptation while overstating the costs of mitigating it. To a lesser extent, climate change denial can also be implicit when people accept the science but fail to reconcile it with their belief or action. Several studies have analyzed these positions as forms of denialism, pseudoscience, or propaganda.