When it comes to climate change, Thom Yorke isn’t scaremongering. This is really happening, happening. The Radiohead frontman signed a letter on Friday urging word leaders who are converging at the 2015 United Nations Climate Change Conference (which begins Monday in Paris) to reach an understanding on the severity of climate change. (David Bowie and Bjork also signed the letter, in case world leaders needed any more convincing.) Yorke also DJed on the Greenpeace float at London’s Climate March parade this weekend, battling wild winds that felt exceedingly appropriate for the march. You can watch snippets of Yorke’s parade set below.