Al Gore November 20, 2019 12:11 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. US & World Videos 5:49 Kelly Clarkson hilariously attempts handmade pasta with chef Evan Funke 1:59 Ellen DeGeneres jokes about being ‘kicked out of show business' 1:36 O.J. Simpson's cause of death revealed 2:03 Does Shakira still believe in love following Gerard Piqué split? 2:36 Super dad makes Mario-themed obstacle course for son's birthday