Is it uncharitable to want a book that achieves so much to do more? Perhaps. Taken on its own terms, “The Human Age” is a dazzling achievement: immensely readable, lively, polymathic, audacious. But as the Anthropocene becomes a defining paradigm of our time, it matters how we frame the challenges ahead. It’s easy to agree with Ackerman’s assessment that “a warmer world won’t be terrible for everyone, and it’s bound to inspire new technologies and good ­surprises, not just tragedy.” But her assertion deserves a follow-up question: Who is in line for the good surprises, and who is queuing up for tragedy? Hurricane Sandy brought precisely that ­question to the fore. Manhattan? Too valuable to lose. Bangladesh, even Far Rockaway, not so much.

The science writer Elizabeth Kolbert has tweeted, “Two words that probably should not be used in sequence: ‘good’ & ‘anthropocene.’ ” Ackerman’s Anthropocene, however, is decidedly sunny side up. Her instinct is to celebrate this new age: “We are dreamsmiths and wonder­workers. What a marvel we’ve become, a species with planetwide powers and breathtaking gifts.” That we are, but we also possess more sobering powers, a recklessness and greed that will be inscribed in the fossil record. Ackerman’s optimism can feel eerily unearned in the absence of a measured acknowledgment of the losses, the traumas, the scars that afflict human and nonhuman communities in this volatile new age. At least pause to ponder this: Is it ethical that as the super­rich capture ever more resources, the poor, who have contributed least to our planet’s undoing, are forced to bear the brunt of the chaotic effects?