Dr. James Hansen is the single most credible scientific voice worldwide on the issue of global warming. In his celebrated first book, Storms of My Grandchildren, he presented the full truth about climate change, a truth born out in the years since as climate disasters continue to ravage our world. The urgency is apparent; the response so far, inadequate.

But Hansen remains an optimist. In a series of moving and insightful letters to his granddaughter, Sophie, he speaks about the fight to preserve life on the planet, a fight that for her generation will be as personal as it is political-as much about policy actions as about the right of the monarch, Sophie's favorite butterfly, to live and thrive on this earth. Sophie's Planet turns toward solutions, asking: How can we connect the dots from climate observations to necessary policies? What can be done to preserve our planet for the young people who will follow us? And how can we make the climate story clear to these young people, to prepare them for what will be one of their generation's central struggles: the fight for environmental justice?

Hansen's conversations with Sophie offer a fascinating glimpse behind the scenes of a life spent at the highest levels of environmental research and policy-including the realms where dark motives prevail-as well as a moving clarion call for the future of the climate change fight.