EPA administrator Lee Zeldin has announced the rollback of 31 environmental regulations. Presidential Distinguished Professor of Earth & Environmental Science at the University of Pennsylvania Michael Mann joins Katy Tur to provide insight on these rollbacks and the devastating consequences they could have on the environment. For more context and news coverage of the most important stories of our day click here: msnbc.com » Subscribe to MSNBC: youtube.com/msnbc » Subscribe to MSNBC on TikTok tiktok.com/@msnbc » Subscribe to MSNBC on Instagram instagram.com/msnbc Download our new MSNBC app for the latest breaking news and daily headlines at a glance: msnbc.com/information/download-msnbc-app-n1241692 Follow MSNBC Show Blogs MaddowBlog: msnbc.com/maddowblog MSNBC delivers breaking news, in-depth analysis of political headlines, commentary and informed perspectives. Find video clips and segments from The Rachel...