It was a cold February in Washington D.C. this year, and a U.S. Senator from Oklahoma threw a snowball in the Senate chamber as part of his argument that global warming is a hoax. This stunt evidences a real problem in the struggle to prevent climate change—confusion over the difference between weather and climate.

Every living thing on earth, including of course its human inhabitants, observes weather on a daily basis. Weather is what we perceive when we step outside—cold or warm, wet or dry, windy or still, and cloudy or sunny. But that is NOT the climate.

If you lived in much of eastern North America last year, or spent time on a ship in the mid-North Atlantic ocean or the Straits of Magellan, your weather this past winter was much colder than normal. When people experience record colds and look no further than what their senses tell them, they might be skeptical about global warming.

But worldwide, according to scientists at the National Oceanic and Atmospheric Administration, the climate in 2014 was in fact the hottest since record keeping began in 1880.  Moreover, the seemingly inexorable warming trend over the past 135 years is unmistakable.

The most thorough analysis I’ve seen confirming planetary climate warming caused by humans was published by the American Institute of Physics (AIP). “Regardless of what had happened in past centuries, the warming since the 19th century was as certain a fact as anything in science” by 2012, according to Dr. Spencer Weart, former director of AIP’s Center for History of Physics. In Dr. Weart’s comprehensive history of the discovery of global warming, he explains: “The coup de grace for people who doubted the climate community’s statistics came from their own ranks. A painstaking re-analysis of land-station data was organized by warming skeptic Richard Muller and funded by oil billionaire Charles G. Koch, a leading sponsor of groups that attacked the climate consensus. The study, using different methods and more data than earlier teams, only confirmed what every other study had found. There was a marked recent rise, Muller’s group announced in 2012, that could only be explained as human-caused.”

Need more evidence that this temperature trend is not part of earth’s long-term regular heating and cooling cycles? Check out this recent article in Scientific American, in particular the top two charts, which show the unmistakable correlation between increasing atmospheric carbon and our climate’s warming temperatures.

Global warming is not a hoax or some vast conspiracy by scientists and journalists. Rational, environmentally conscious people may ask themselves why many of their neighbors (and political leaders) continue to question the reality of increasing planetary temperatures.  Yet skeptics do, and one of the reasons, forcefully demonstrated by the Senator from Oklahoma, is the confusion between climate and weather. And this confusion is dangerous in the face of the scientific consensus on climate change.