Decades-old video shows Vermont Senator Bernie Sanders was calling for action on climate change, at least as far back as 1987. You can watch those videos below. The first video shows Sanders in 1989, during an interview on C-SPAN in which he slammed the media for not covering climate change enough. The second video shows Sanders in 1987, talking to a classroom of middle school students about the greenhouse effect.

Here’s the C-SPAN interview, from 1989:

There's a 1989 C-SPAN interview where Bernie blasts the media for not covering climate change, "the greenhouse effect." pic.twitter.com/9uXk2qh8re — andrew kaczynski (@KFILE) March 5, 2019

Here’s the video of Sanders in the classroom, in 1987:

Here he is talking to students about climate change in 1987 pic.twitter.com/x4PrMan2Tq — People for Bernie (@People4Bernie) March 5, 2019

Sanders told C-SPAN, “We face, as all people know, an ecological crisis in our time, whether it’s acid rain, the destruction of the ozone layer, the greenhouse effect. One would think that the CBS’s, the NBC’s of the world would be doing prime time specials on these problems. Having different scientists, talking about the issues. Involving people in understanding what’s going on in terms of our planet. They don’t. The function of television is to make as much money as possible for the owners of the television station and for those people who advertise, for 30 second ads on television. So I would say that we’re not going to bring about serious political change in this country until we deal with the media, which more and more is being swallowed up by large conglomerates. Very important issue.”

Two years earlier, in 1987, Sanders spoke to a classroom of middle school students. He told them,

“Some of you may have seen, there were some articles in the newspaper recently about the destruction of the ozone layer and the fact that the climate, the temperature on Earth, may rise a few degrees. Is that significant? Or does that just mean that the summer will be a little bit warmer and we can go swimming another day or two?”

Sanders calls on a boy named “Ed,” who says, “It doesn’t seem significant, but if it gets hardly any warmer, the polar ice caps could melt and flood the oceans.”

“Precisely,” says Sanders.