There is no debate on the cause of climate change. It’s caused by human activity, in particular CO2 emissions. End of debate. What Marc Rubio really means is that there are organizations funded by the Koch brothers, ExxonMobil, and other fossil fuel insterests, and they’ve been paying junk scientists to cherry-pick and manipulate data to deliberately cause confusion and delay. Please keep in mind that Exxon is the most profitable American company; they made $45 billion in profits just last year. And that’s just Exxon. The fossil fuel industry makes BIG money. The huge amount they’ve been spending on lobbying congress and creatingadeliberate campaign of misinformation is chump change to them. The “scientists” they’ve paid do not even publish peer reviewed scientific papers; they’re paid industry spokespeople. What do the real climate scientists say about climate change? They say it’s real, it’s very serious, it’s happening faster than predicted, and it’s caused by humans. Peer reviewed papers by climate scientists agree with this consensus. >97% climate scientists agree with this consenus. So does the Academies of Science from 19 countries and all the following scientific organizations: the National Academy of Sciences, NASA, the USGS, NOAA, the American Meterological Society, the IPCC, the National Center for Atmospheric Research, American Astronomical Society, Royal Meteorological Society, American Chemical Society and the American Institute of Physics. Climate change is caused by humans and that means we can and should do something about it.