This is a serious (no joke!) Mankiw follow-up video about climate change; START AT THE 4:55 MINUTE MARK. I don’t have a downloadable version of this, but if YouTube is blocked in your country you can get an earlier (and inferior) version of most of this material if you right-click here and choose “save as” to download an MP4 file to your computer. (To play it, PC users might need a free download of this QuickTime player.)