NBC weatherman Al Roker debunked EPA head Scott Pruitt’s false claim that carbon dioxide is not a primary contributor to global warming during an appearance on MSNBC Live, explaining that there is “no credible science or scientist” to support Pruitt’s statement.

During the March 10 segment, Roker addressed Pruitt’s comments on the March 9 edition CNBC’s Squawk Box in which Pruitt said “I would not agree” that CO2 is “a primary contributor to the global warming that we see” -- a statement completely at odds with the consensus among climate scientists that human activity is the primary cause of climate change.

To rebut Pruitt’s statements, Roker referenced an interview he recently conducted with climate scientist Dr. Marshall Shepherd, who explained that “greenhouse gases are in fact the primary forcing function on a warming climate system. … their fingerprint is there on our naturally varying climate in the same way steroids were on the naturally varying cycle of home runs during the Major League Baseball era.”

Roker also stated “there is no credible science or scientist” that would back up Pruitt’s assertion. Indeed, a number of climate scientists have weighed in on Pruitt’s statement, stating Pruitt’s denial “demonstrated that he is unqualified to run the EPA or any agency” and suggesting that Pruitt “talk with his own scientists and read the National Climate Assessment.”

Notably, however, NBC did not address Pruitt’s climate denial on the widely viewed Today show the same day, nor NBC Nightly News air a segment on Pruitt’s climate denial on March 9 -- even though Pruitt’s denial received widespread attention across mainstream media.

From the March 10 edition of MSNBC Live:

KATY TUR (HOST): The head of the Environment Protection Agency stunned many when he denied carbon dioxide is a primary contributor to global warming.

[...]

TUR: Today show host and weatherman, a man who needs no introduction, Al Roker joins me now. “Stunned many” is a bit of an understatement, said most almost all, gosh, CO2 is not a factor when it comes to climate change. Was all of the schooling that I had as a child and into my adult life completely wrong, Al Roker?

AL ROKER: No, it wasn't wrong and there is no credible science or scientist who will tell you the contrary. The fact is, carbon dioxide, the greenhouse gases is responsible for climate change.

TUR: No scientist will say this, but we’re having the EPA head say this?

ROKER: Well, look, this is America and you can make whatever statements you want to, but everybody will pretty much agree -- in fact, just about an hour ago I interviewed one of the leading climate scientists in this country, Dr. Marshall Shepherd, and here's what he had to say about it.

[BEGIN VIDEO CLIP]

MARSHALL SHEPHERD (DIRECTOR FOR UNIVERSITY OF GEORGIA’S PROGRAM IN ATMOSPHERIC SCIENCES): The basic physics of the atmosphere suggest that greenhouse gases are in fact the primary forcing function on a warming climate system. Greenhouse gases and the impacts post-industrial age or -- industrial revolution are certainly -- their fingerprint is there on our naturally varying climate in the same way steroids were on the naturally varying cycle of home runs during the Major League Bbaseball era.

[END VIDEO CLIP]

ROKER: I think that pretty much sums it it up.

TUR: Yeah, so where -- if the EPA head is saying there needs to be more research, but the EPA is losing money to do research, give me the consequences. How important is it and how significant is it to have the EPA head deny something like this?

ROKER: Well I think hopefully cooler heads will prevail upon him to say we need to continue to research this. We need to continue what we've been doing because if you look, we've got a graphic that basically right around the industrial revolution, we had -- there's been no time in this history of our planet where CO2, even naturally occurring or not, was above 290 parts per million. Alright, now you look at the temperature, we put the temperature on top of that, you can see from the 1880s into the 1940s, temperatures are below average, below the global average, but once we really start to see that red line go up, as the CO2 starts to increase, you can see those average global temperatures continue to rise, and they peaked last year, the warmest temperature ever on record for this planet. So as we continue to add those greenhouse gases -- now, that's not to say that -- the greenhouse gases allow us to live on this planet. Without them completely, we would freeze to death. At night we would die. So there has to be some small amount of greenhouse gases. We're just adding too much.