Episode 15 of Cool Tunes for a Hot Planet kicks off May 1st. May Day has been celebrated for centuries as a celebration of rebirth, fertility, and the mystery of life – and then a further declaration of workers' rights since the late 19th century. But in addition to name-checking May Day, today's episode presents songs by singer-songwriters from MusicToLife.org – a nonprofit organization that mentors young musicians with a mission to work in their communities for social and environmental justice. Songs include Walkin' the Hi-Line, by Jocelyn Wilkinson and Don Barrozo, a story-song about Don's immigrant father working on the railroad; Fjorden Er Ikke Var, by Hilja, a paean to the fjords of Norway, and the protests against their destruction by industrial development; and Lara Herscovitch's Letters From a Ghost, invoking the spirit of Martin Luther King to urge us on in the work we all must do to celebrate love, not hate, on May Day and every day.