Half a degree stole the climate spotlight in 2018
New data show limiting warming to 1.5 degrees Celsius, not 2 degrees, will make a difference
The grim reality of climate change grabbed center stage in 2018.
This is the year we learned that the 2015 Paris Agreement on global warming won’t be enough to forestall significant impacts of climate change. And a new field of research explicitly attributed some extreme weather events to human-caused climate change. This one-two punch made it clear that climate change isn’t just something to worry about in the coming decades. It’s already here.
This looming problem was apparent three years ago when nearly all of the world’s nations agreed to cut greenhouse gas emissions to limit global warming to no more than 2 degrees Celsius over preindustrial times by 2100 (SN: 1/9/16, p. 6). That pact was hard-won, but even then, some scientists sounded a note of caution: That target wouldn’t be stringent enough to prevent major changes.