Nor, as Idsos father Dr. Sherwood Idso points out, is there any doubt in the scientific community that the temperature increase associated with an interglacial period precedes an increase in carbon dioxide concentrations. Ice core data shows this relationship quite clearly and Al Gores misrepresentation of this fact, by skewing data in An Inconvenient Truth to make it seem that carbon dioxide concentrations have historically caused, rather than followed, temperature changes is one of the more glaring errors in his film.