In the prologue for their book At Every Depth: Our Growing Knowledge of the Changing Oceans, UC Davis scientist Tessa Hill and writer Eric Simons open with an astute observation about humanity’s relationship with the ocean. 

“Even though one-third of the people on the planet live within sixty miles of a coast, the ocean appears as a featureless expanse for most of us; it is an open blue palette separating the places where life happens,” the authors write. “In reality, it is a mosaic as breathtakingly nuanced as the fields and cities and hills and valleys we know on land.”

But the observation is paired with a warning. 

“That mosaic,” the authors continue, “is experiencing unprecedented change: coral reefs are turning white, animals migrating to unusual places, ice sheets melting, and fish stocks that people have relied on for millennia dwindling.”

While so much of the big blue is still a mystery to us, the beauty and life within it are being affected by our choices as a species. In some ways, the oceans are changing faster than we can study them.

At Every Depth, published by Columbia University Press this February, chronicles those changes through the eyes of the community members closest to the shores. But the book is not a passive volume. Instead, it’s a call to action.

“At its heart, the book is all about how the human relationship with the ocean is changing and to accomplish that, my coauthor Eric Simons and I interviewed dozens of people who are expert observers of what is happening in the oceans,” said Hill, an earth and planetary sciences professor in the College of Letters and Science at UC Davis. “There are scientists, coastal community members, fishermen, Indigenous knowledge holders, and community and citizen scientists. We really wanted to talk to people about what they see with the ocean changing, what it means to them, what that change means for their communities and what they’re doing about it.”

In every chapter, each of which covers a specific ocean environment from the tide pools to the deep, Hill and Simons share personal narratives of the people witnessing, documenting and responding to the sea changes occurring in our waters.  

“These folks are making a conscious choice to enter this field at this time when it can be a little bit sad, a little bit heartwrenching,” Hill said. “But it is that conscious choice and wanting to do things that move us in a positive direction.”

Writing during the pandemic

Hill and Simons started thinking about collaborating on a book back in 2017. The two met when Simons, a science journalist from the Bay Area with two book publications under his belt, interviewed Hill for an article. They struck up a correspondence, the conversation eventually turning to reporting and storytelling about the ocean.

“At some point, one of us said to the other, ‘Hey, we should start writing some of this down,’” Hill recalled. “That was the genesis of it.”    

As they ideated more, the two decided to organize a book proposal. In 2018 Hill took a sabbatical from UC Davis, which gave her more time to dedicate to the book project. Hill and Simons sketched out the book’s outline and wrote a first chapter, an adaption of which was published in Bay Nature Magazine under the title “A Tidepool in Time.” The essay traces the history of the changing rocky shores of Monterey Bay through stories told by scientists and the Native people of Monterey, the Rumsen Ohlone, who have lived on the shores for thousands of years.

In early 2020, Hill and Simons secured a contract with Columbia University Press to publish the book. Then, the COVID-19 pandemic hit and the world shut down.

“Despite our best plans, we wrote almost the entire book not being able to interview people in person,” Hill said. “In some ways that was hard, but in some ways it opened up possibilities for the book that I don’t think would have ever existed.”

In a paradoxical turn of events, the pandemic provided Hill and Simons with deeper insights and access to their interviewees.

“It was actually very personal and very open,” Hill said. “There were times when we would Zoom with people and they were in their homes, showing us their lives and their worlds in a way that we never would have seen if we had just visited them in their offices. We had people pick up their computers and take us outside to the ocean in their backyard.”   

The Zoom nature of existence at the time also allowed Hill and Simons to attend lectures and seminars that otherwise would have been inaccessible, primarily due to location. It ended up broadening the scope of the research and stories the authors included in the book. 

A shoal of knowledge

Hill and Simons crafted At Every Depth with the intent of eschewing hierarchies of knowledge. No one view is held above another. Rather, the work is a tapestry of knowledge across peoples and professions.

“We value knowledge about the ocean, period,” Hill said. “We did not decide what knowledge is better than others. People who have spent their lives near the ocean, observing the ocean over multiple generations, that knowledge is just as valuable as Western scientific knowledge.”

While Hill is a prolific science communicator and scholar, At Every Depth marks her first book-length “popular science” publication. With it comes a newfound sense of vulnerability, and potentially a wider swath of readers. Already, the book has made its way to “most anticipated” book lists for 2024, including lists published by Book Riot and The Independent.

“I hope that it meets people’s expectations,” Hill said. “Hopefully, the book also lands with a note of action and optimism and hope, because certainly there are a lot of changes happening with the ocean, but there are also people working very hard to keep our relationship to the ocean sustainable.”