Dr James Hansen, the world's leading scientist on climate issues, speaks out for the first time with the full truth about global warming: the planet is hurtling to a climatic point of no return. Hansen - whose climate predictions have come to pass again and again, beginning in the 1980s when he first warned US Congress about global warming - is the single most credible voice on the subject worldwide. He paints a devastating but all-too-realistic picture of what will happen if we continue to follow the course we're on. But he is also a hard-headed optimist, and shows that there is still time to take the urgent, strong action needed to save humanity.