New Jersey November 20, 2019 3:11 am ‘Late Night': Al Gore Calls Climate Change Most Serious Challenge Al Gore calls climate change the most serious challenge human civilization has ever faced and talks about an upcoming global event for climate change awareness. Local 0:34 City College of New York goes remote as protests continue 14:23 NYPD arrests around 100 protesters at Columbia University 29:11 NYPD moves in on protesters at Columbia University making dozens of arrests 1:45 NYPD enters Columbia University in riot gear to clear protest 3:24 Mayor Adams and the NYPD urge protesters to leave Columbia University