WEBVTT 00:00:01.950 --> 00:00:05.240 [Kristen] Why is 1.5 degrees such a big deal? 00:00:05.240 --> 00:00:10.170 Because to warm our entire planet up by 1.5 degrees Celsius 00:00:10.170 --> 00:00:12.510 requires a lot of heat. 00:00:12.510 --> 00:00:16.180 All this extra heat melts glaciers, which raise sea levels. 00:00:16.180 --> 00:00:17.950 If the ice sheets of Antarctica 00:00:17.950 --> 00:00:19.750 and Greenland melt completely, 00:00:19.750 --> 00:00:22.850 millions of people's homes will be underwater. 00:00:22.850 --> 00:00:25.200 The extra heat also intensifies weather, 00:00:25.200 --> 00:00:28.110 making wet places wetter, dry places drier, 00:00:28.110 --> 00:00:30.660 and increasing the ferocity of storms. 00:00:30.660 --> 00:00:34.740 That 1.5-degree increase also won't be distributed evenly. 00:00:34.740 --> 00:00:36.480 The coldest nights in the Arctic 00:00:36.480 --> 00:00:38.320 might get 10 degrees warmer. 00:00:38.320 --> 00:00:41.650 The warmest days in Mumbai might get five degrees hotter. 00:00:41.650 --> 00:00:44.500 Over the past 10,000 years, we've been lucky. 00:00:44.500 --> 00:00:48.260 Earth's climate was stable and our civilizations flourished. 00:00:48.260 --> 00:00:50.580 But as our climate gets more unstable, 00:00:50.580 --> 00:00:53.720 so will our economies and our societies. 00:00:53.720 --> 00:00:57.700 We'll all suffer and the vulnerable will be hit hardest 00:00:57.700 --> 00:00:59.153 unless we act now.