Following President Trump's comments refuting a US government report on climate change, we talk to Katharine Hayhoe -- one of the scientists who wrote it. She explains why it's so hard to get Republicans and Democrats on the same page about climate change. » Subscribe to NBC News: nbcnews.to/SubscribeToNBC » Watch more NBC video: bit.ly/MoreNBCNews NBC News Digital is a collection of innovative and powerful news brands that deliver compelling, diverse and engaging news stories. NBC News Digital features NBCNews.com, MSNBC.com, TODAY.com, Nightly News, Meet the Press, Dateline, and the existing apps and digital extensions of these respective properties. We deliver the best in breaking news, live video coverage, original journalism and segments from your favorite NBC News Shows. Connect with NBC News Online! Visit NBCNews.Com: nbcnews.to/ReadNBC Find NBC News on Facebook: nbcnews.to/LikeNBC Follow NBC News on Twitter: nbcnews.to/FollowNBC Follow NBC News on Instagram: nbcnews.to/InstaNBC Co-Author Of Climate Change Report Responds To President Donald Trump | NBC News Signal