"Horizon" (Alfred A. Knopf), by Barry Lopez

Part travel journal, part history, part science lecture, part autobiography, and completely unique, "Horizon" feels like the crowning achievement of Barry Lopez's illustrious career.

Fans of his National Book Award-winning "Arctic Dreams" (1986) and subsequent books about little understood landscapes, cultures and wildlife will find much to love here. Readers who have never read Lopez might be better served reading one of his single-topic tomes first.

At 512 pages, this book is dense. It's divided into six main parts based on the geography of Lopez's lifelong travels — western Oregon, the High Arctic, the Galapagos, Kenya, Australia and Antarctica. There are maps that help readers visualize where our peripatetic narrator is at any given time, but not much else in the way of context. Lopez admits in the prologue that he consciously chose to simply tell stories, not explain any "juxtapositions in time," but it would have provided readers with helpful perspective to know more about his life circumstances during any given trip.

The resulting feel of the book is fragmented — perhaps intentionally mirroring the way memory works? — with passages about the power of music to "pry something ineluctable out of a particular landscape" (listening to Beethoven's Fifth Symphony on Skraeling Island, 660 nautical miles from the North Pole) just 20 pages removed from a technical explanation of how the Antarctic Moon and Neutrino Detector Array at the South Pole works.

Each of the chapters is jammed with stories and personal reflections. Lopez, perhaps more than any other nature writer alive, is introspective to his core. Every experience, every sight, every person he meets, has made an impression on him and unlike most of us he kept notes. This book is his attempt to look back on it all and say something about the world we share.

Here he is after looking at a piece of chalk white sandstone in his office, remembering the outrage he felt about acts of global genocide the day he picked it up on a beach in San Salvador: "What cataclysm, I often wonder, or better, what act of imagination will it finally require, for us to be able to speak meaningfully with one another about our cultural fate and about our shared biological fate?"

Yet despite all the injustice he's seen in the world and the irrefutable science showing how humans are altering the climate, Lopez manages to convey in his prose a sense of hope. Have you ever had a moment in your life when everything seems right with the world, that you'll be OK no matter how hard any given task might be? Lopez shares one walking through a park in Sydney, Australia: "The most fragmentary of breezes occasionally unsettled the leaves of gum trees. The delicacy of the weather reinforced a feeling I had in that moment of unfocused exuberance, a faith that no matter what people had to face in the world that is coming for us, they would fare well. Whatever the nightmare, some group of us would see a way through, for ourselves and others."

Whether you personally lean toward the cynical or hopeful, one thing is certain — we need adventurous, curious souls like Lopez to keep traveling and bringing back stories from beyond our particular horizon — in order to find our way forward as a species, together.