0:00:01.896,0:00:05.216
Why is 1.5 degrees such a big deal?

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Because to warm our entire planet up[br]by 1.5 degrees Celsius

0:00:10.170,0:00:12.478
requires a lot of heat.

0:00:12.502,0:00:16.156
All this extra heat melts glaciers,[br]which raise sea levels.

0:00:16.180,0:00:19.726
If the ice sheets of Antarctica[br]and Greenland melt completely,

0:00:19.750,0:00:22.478
millions of people's homes[br]will be under water.

0:00:22.799,0:00:25.176
The extra heat also intensifies weather,

0:00:25.200,0:00:28.070
making wet places wetter, dry places drier

0:00:28.094,0:00:30.616
and increasing the ferocity of storms.

0:00:30.640,0:00:34.716
That 1.5-degree increase[br]also won't be distributed evenly.

0:00:34.740,0:00:38.296
The coldest nights in the Arctic[br]might get 10 degrees warmer.

0:00:38.320,0:00:41.602
The warmest days in Mumbai[br]might get five degrees hotter.

0:00:41.626,0:00:44.476
Over the past 10,000 years,[br]we've been lucky.

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Earth's climate was stable[br]and our civilizations flourished.

0:00:48.260,0:00:53.696
But as our climate gets more unstable,[br]so will our economies and our societies.

0:00:53.720,0:00:55.153
We'll all suffer,

0:00:55.177,0:00:57.638
and the vulnerable will be hit hardest,

0:00:57.662,0:00:59.415
unless we act now.

0:01:02.363,0:01:03.949
[Countdown

0:01:03.973,0:01:06.753
Take action on climate change[br]at Countdown.ted.com]