As the UN climate negotiations kick off in Doha, Qatar, people all over the world are watching as floods wash away their lives, fires consume their houses and droughts decimate food crops. Just this morning, UNEP released a report warning that melting permafrost could release massive amounts of methane–a powerful greenhouse gas–into the atmosphere, bringing the planet ever closer to runaway climate change. Here’s a letter from three powerful advocates for a safe climate to the leaders and negotiators in Doha: