If the global pandemic is leaving you wanting more on the existential angst front, try dipping into chapter 6 of journalist and former activist Mark Lynas' new book, 'Our Final Warning', where you'll read that at six degrees of global heating "a wave of mass extinctions threatens life on earth". Theeeeeeere we go, that's the good stuff.The book, to an extent an updated version of 2007's groundbreaking 'Six Degrees', describes the most recent scientific understanding of what we can expect if carbon emissions don’t fall rapidly and temperatures continue to rise. Or, in other words, the civilisation-ending shitstorm that's in the post if humanity doesn't get its act together PDQ.We chat to Mark about what's changed - good and bad - in the twelve years between the two books, what Covid-19 might mean for global emissions, and why, despite it all, he retains a sense of optimism.Sustainababble is your friendly environment podcast, out weekly. Theme music by the legendary Dicky Moore – @dickymoo. Sustainababble logo by the splendid Arthur Stovell. Ecoguff read out by Arabella.Love the babble? Bung us a few pennies at www.patreon.com/sustainababble.MERCH: sustainababble.teemill.comAvailable on iTunes, Spotify, Acast & all those types of things, or at sustainababble.fish. Visit us at @thebabblewagon and at Facebook.com/sustainababble. Email us at [email protected].