Experts say world temperatures are spiraling upward. This graphic — it’s already gone viral —  shows just how fast.

Climate scientist Ed Hawkins of the University of Reading in the U.K. took 166 years of monthly global average temperatures and created a compelling, animated visual:

Why is this important? Since pre-industrial times, the burning of fossil fuels has released huge amounts of heat-trapping carbon dioxide into the atmosphere. A global temperature increase of 2 degrees Celsius puts the world well within the climate change “danger zone.”

With that 2 degree increase, scientists project prolonged droughts, more severe weather and sea level rise of up to a meter or more.

One of the chief aims of the December 2015 international Paris agreement is to stop the temperature increase well below 2 degrees Celsius, and to pursue efforts to limit it to 1.5 degrees.