The United Nations climate change talks ended with a major global deal. Ali Velshi speaks with one of the authors of the latest U.N. report on climate change, Katharine Hayhoe, about what’s in the deal and the most important thing you can do to fight climate change. » Subscribe to MSNBC: on.msnbc.com/SubscribeTomsnbc About: MSNBC is the premier destination for in-depth analysis of daily headlines, insightful political commentary and informed perspectives. Reaching more than 95 million households worldwide, MSNBC offers a full schedule of live news coverage, political opinions and award-winning documentary programming -- 24 hours a day, 7 days a week. Connect with MSNBC Online Visit msnbc.com: on.msnbc.com/Readmsnbc Subscribe to MSNBC Newsletter: MSNBC.com/NewslettersYouTube Find MSNBC on Facebook: on.msnbc.com/Likemsnbc Follow MSNBC on Twitter: on.msnbc.com/Followmsnbc Follow MSNBC on Instagram: on.msnbc.com/Instamsnbc What’s The Most Important Thing You Can Do To Fight Climate Change? | Velshi & Ruhle | MSNBC