On Sunday, Donald Trump Jr. tweeted out a photo of Anderson Cooper standing in waist-deep water during a hurricane and claimed that CNN was "lying" and attempting to make his father "look bad."

This was a variation on a meme that made its way around conservative online circles, which accused Cooper of faking a shot to make the flooding look even worse than it was.

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You know it’s sad when even the WEATHER is #FakeNews. 🤬😤 #StayWokeMyFriends

A post shared by 🇺🇸 lynnepatton (@lynnepatton) on Sep 15, 2018 at 1:59pm PDT

The one problem: it's fake news.

So, Cooper took a few minutes during 'AC 360' last night to scold Don Jr., saying, “I debated whether I should even respond tonight to the president’s son.”

He went on:

"I know he considers himself an outdoorsman and pays a lot of money to be led to wildlife in Africa that he then kills. But I’m not sure if he’s actually been to a hurricane or a flood. I didn’t see him down in North Carolina over the last few days helping out, lending a hand, but I’m sure he was doing something important besides just tweeting lies.”

One problem with the photograph is that it wasn't taken during Hurricane Florence, which battered the Carolinas over the past several days, but rather it was taken during Hurricane Ike in 2008. Trump Jr. shared the photo without context, and it was promptly retweeted more than 22,000 times.

Cooper displayed Trump's tweet on the air and also shared some of the responses that followed.

Some guy said I was on my knees to make it look deep and then went on to say that I was used to being on my knees, which I assume is some sort of anti-gay reference,” he said. “Very classy.”

Cooper pointed out that at the time the photo was taken, he had actually told viewers that the floodwaters had receded. CNN had also shown footage of emergency vehicles driving down a road which was not nearly as flooded.

“You can argue I didn’t need to be standing in waist-deep water,” Cooper said. “I could have been standing on the road by the camera crew. But, again, I didn’t want to be roaming around on the highway interfering with rescue vehicles in any way. I also wanted to show people how deep the water was and how dangerous it is for anyone driving. It’s easy to make fun of someone standing in water reporting. I get that."

Cooper also explained why he'd chosen to devote so much time on his show to debunking Trump Jr.'s tweet:

“I rarely respond to online conspiracy theorists or cable news cranks looking to get into a mutually beneficial beef that will boost their ratings... I’ve covered hurricanes for about 14 years and it really does make me sad to think that anyone would think that I would try to fake something or overly dramatize a disaster... Look, I don’t expect the president’s son to ever admit that he was wrong or one of the president’s advisers or frankly anyone else who’s retweeted any of these pictures. But I at least thought that they and you should know the truth.”

Critics embraced Cooper's thorough debunking of the lie, and Trump Jr. was soon assailed for propagating it.

Hurricane Florence has killed more than 30 people, and Trump Jr. was also called out for suggesting that the damage wrought by the storm is not as severe.

President Donald Trump himself made headlines last week for discrediting the extent of devastation in Puerto Rico following Hurricane Maria, though his administration's response to the current disaster has been considerably more prompt.