Why was 2015 the hottest year ever?

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Climate scientist says climate is resilient to a point, but time is running out
05:42
John Kerry: Climate change is a universal threat; we all need to be engaged
05:11
'We're in a place to win the battle': Kerry sounds hopeful note on climate (with a big 'if')
08:51
Biden launches Climate Corps; pairs new jobs with climate, infrastructure work
06:30
Kyra Sedgwick on taking climate action: 'You can't just do this halfway'
04:45
Lewis Pugh: Rivers are ‘arteries of our planet,’ we need ‘healthy rivers’ for a ‘healthy planet’
04:25
One-on-one with Spencer Glendon
07:42
Young Republicans are pushing their party on climate change
06:13
Follow the money: Fracking billionaires funding anti-renewable energy propaganda cartoons
04:41
'Insurance companies know': More people vulnerable as cost of climate disasters rises
02:28
Hayes blasts ‘deranged’ GOP climate plan: ‘Hurl ourselves into the fire’
04:31
Extreme heat, rain, and drought across the country is climate change “in all of its forms.”
03:43
Worse than a 'new normal': Bill Nye on tropical storm Hilary, climate change
04:48
Sen. Schatz: “The people of Maui are strong, but we're going to need help from everybody.”
06:42
Republican Presidential candidate Ramaswamy’s controversial views on foreign policy & climate change
07:34
At least 111 killed, hundreds missing in Hawaii wildfires as electric company sued
05:41
‘Rare and historic’: California under first-ever tropical storm watch
06:46
Maui death toll continues to rise, slow progress made on identifying victims
02:01
FEMA on support efforts in Maui 'Absolutely heartbreaking experience'
06:20
Gov. Whitmer: ‘Voters are not stupid’ and ‘they know who's really working to improve’ their lives
08:24

UP NEXT
Climate scientist says climate is resilient to a point, but time is running out
05:42
John Kerry: Climate change is a universal threat; we all need to be engaged
05:11
'We're in a place to win the battle': Kerry sounds hopeful note on climate (with a big 'if')
08:51
Biden launches Climate Corps; pairs new jobs with climate, infrastructure work
06:30
Kyra Sedgwick on taking climate action: 'You can't just do this halfway'
04:45
Lewis Pugh: Rivers are ‘arteries of our planet,’ we need ‘healthy rivers’ for a ‘healthy planet’
04:25