In response to President Donald Trump's tweet late Monday night, 16-year-old climate activist Greta Thunberg clapped back by changing her Twitter bio.
The president's tweet shared a video, originally tweeted by Wired, which quoted Thunberg saying, "People are suffering, people are dying, entire ecosystems are collapsing. We are in the beginning of a mass extinction and all you can talk about is money and fairytales of eternal economic growth."
The president added his own commentary to the tweet, saying, "She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see!"
Less than twelve hours later, Thunberg's Twitter bio was changed to say, "A very happy young girl looking forward to a bright and wonderful future."
Trump was apparently being sarcastic with his remark, as Thunberg's message at the United Nations Climate Action Summit on Monday painted a picture that was anything but a "bright and wonderful future."
"You have stolen my dreams and my childhood with your empty words," she said. "Yet, I'm one of the lucky ones."
She also criticized current solutions to climate change in her speech, deeming them inadequate.
"The popular idea of cutting our emissions in half in ten years only gives us a 50 percent chance of staying below 1.5 degrees and the risk of setting off irreversible chain reactions beyond human control," she said. "So a 50 percent risk is simply not acceptable to us, we who have to live with the consequences."
Some people on Twitter are poking fun at the situation, like New York Times reporter, Astead Herndon. In a tweet sharing Thunberg's new bio he commented, "getting in social media fights with the youths is a dangerous game. The whole internet is their home court advantage."
This isn't the first time Thunberg has shown her disapproval of the president. Trump briefly made an appearance to the Climate Action Summit, and a video has been circulating showing Thunberg glaring at the president as he passed.
Thunberg rose to fame with her Friday for Future campaign, encouraging students in Sweden and eventually worldwide to walk out of school on Fridays in support of climate action. Her movement was the catalyst for the global climate strike that took place last week, which was likely the largest climate rally ever.
"We are in the beginning of a mass extinction and all you can talk about is money and fairytales of eternal economic growth," she told world leaders at the U.N. this week. "How dare you?"