In the new video above, Bill Nye the Science Guy explains why climate change is much more than a buzzword. “It’s a real and serious issue,” he says.

In fact, the world’s leaders are debating what to do about it this week in Paris. It’s true Earth’s climate has changed through time naturally due to slight changes in the planet’s orbit, Nye notes, “but climate change as we know it today is characterized by an abrupt increase in the Earth’s temperature.”

That’s 1.2 to 1.4 degrees Fahrenheit warmer over the past century. Ten of the last 13 years were the warmest on record (including this year, according to a recent report). And 97 percent of climate scientists think