WHAT IS CLIMATE CHANGE?
THE SCIENCE IS SETTLED
We know it’s happening, and we know why: carbon pollution from fossil fuels is warming our planet and throwing natural systems out of balance. You don’t have to look far to see the results. Hotter temperatures, stronger storms, rising seas, and so much more, threatening the health of our families and the future we pass on to generations to come.
WHAT’S GLOBAL WARMING AND CLIMATE CHANGE?
Some people use the terms “climate change” and “global warming” interchangeably, so to get to a definition of the one, we’re going to talk about them both because they are profoundly linked but not exactly the same thing.
“‘Global warming’ refers to the long-term warming of the planet. Global temperature shows a well-documented rise since the early 20th century and most notably since the late 1970s,” according to NASA. “Worldwide, since 1880 the average surface temperature has risen about 1° C (about 2° F), relative to the mid-20th-century baseline (of 1951-1980).”
This rise in global temperatures is causing our climate – the average weather patterns for a particular region over a long period of time, typically 30 or more years – to change.
So, “climate change” is a broad, general term for these changes. It’s largely the consequence of the warming described above, and includes everything from the increasing incidence of extreme weather events like powerful hurricanes and severe drought to more frequent flooding and longer-lasting heat waves. It’s the accelerated ice melt we’re seeing in Greenland, Antarctica, and the Arctic and the related rise in global sea levels rise. It’s worsening pollen seasons, spreading vector-borne diseases, and much, much more.
THIS IS WHAT WE KNOW:
Carbon pollution from burning fossil fuels like coal, oil, and natural gas is warming our planet and causing climate change.
It’s simple: the more carbon pollution in the air, the more the sun’s energy gets trapped as heat. Which means things keep getting hotter. You’ve almost certainly heard the phrase “global warming”? In fact, the world has already gotten nearly 1°C warmer since 1880.
Warmer temperatures have real consequences for all of us—not just for polar bears. Sea levels around the world have risen nearly 20cm (7.8 inches) since 1901, swallowing entire islands and creeping closer to populated areas of great coastal cities like New York, Melbourne, and Dakar.
Plus, extreme weather events like hurricanes, floods, and droughts are becoming more frequent and intense. Witness the devastation in 2017 as Hurricane Harvey tore through the Caribbean and the southern US, destroying homes and leaving millions without power for weeks and even months.
“The warming that we’ve seen in the last 30 years is clearly due to human-made
— JAMES HANSEN Former director, NASA Goddard Institute for Space Studies