There’s little in this world more soothing than turning on a nature documentary and hearing David Attenborough’s calm, steady voice. Even as a disembodied narrator, the 94-year-old presenter has become such a ubiquitous presence that watching any nature doc without him feels strange, as if trying to put on a shoe before realizing it’s on the wrong foot. This month, in fact, Attenborough’s voice anchors two separate productions: Apple TV Plus’ documentary “The Year the Earth Changed” (out April 16) and Netflix’s “Life in Color” (out April 22). In both, he proves why he has become the go-to authority on the natural world as he highlights wonder and warnings with equal urgency.

“Life in Color” focuses mostly on the specifics of wildlife versus its place in the world at large. Making occasional appearances onscreen to marvel at a primary-colored macaw or two, Attenborough narrates the series with gentle ease, guiding the viewers through three episodes of stunning footage captured by cameras specifically constructed for this production to pick up as much detail as possible. “Life in Color” is for all those who tune in to nature documentary in the hopes of being dazzled by the majesty on display. It’s as vibrant as its animal subjects, making it easy to identify with the unmistakable note of awe in Attenborough’s voice as he explains exactly what we’re looking at.

“The Year the Earth Changed,” by contrast, is much more explicit about the human race’s role in the natural world. Directed by Tom Beard, the film takes a unique look back at the past year under pandemic lockdown by showing all the ways in which the natural world thrived once human activity suddenly slowed down. Checking in on various locations a month, two months, six months, a year into human quarantine, the 48-minute documentary makes a compelling case for how much damage humans cause on a daily basis, and how much we could help revive the endangered planet by simply adjusting our behavior to coexist more peacefully alongside the animal kingdom.

Beard and his various camera crews show us turtles getting full access to a beach for the first time in decades, penguins getting back to their chicks in a fraction of the time without having to factor in human crowds, and a dormant luxury safari site becoming a fertile feeding ground for a leopard who can now ditch his nocturnal hunting habits. It’s striking, and more than a little depressing, to realize just how badly humans treat our surroundings every day, and how devastating it can be for everything else that lives there. Attenborough did not produce “The Year the Earth Changed,” but in tapping him to deliver its message, the team behind the documentary knows exactly what it’s doing.

Over the years, Attenborough and the projects in which he’s chosen to participate have threaded their awe of nature with an increasingly dire warning about its man-made decline. This became especially unavoidable in 2016’s “Planet Earth II,” the highly anticipated follow-up to the game-changing “Planet Earth.” (Attenborough wrote and performed the narration for both, and not for nothing: it says everything about how synonymous Attenborough became with “Planet Earth” that the gambit of casting Sigourney Weaver as narrator for the first series’ American broadcast was not repeated for the second.)

When “Planet Earth II” added a specific “Cities” episode, it not only showed off the production’s incredible ability to capture life in all corners of the world, but its determination to make its viewers understand not just how catastrophic climate change could be, but how much damage it’s already done. In one particularly terrible sequence, “Cities” demonstrates exactly how awful it can be for those turtles when humans swarm their beaches and build highways alongside them, showing a doomed procession of babies waddling onto a busy road. At the end of that episode, and thus the series, Attenborough chose a blunt conclusion. “The potential to see animals thriving within our cities is achievable across the globe,” he insists. “More than half of us now live in urban environments. Whether we choose to create a home for others, too, is up to us.”

Attenborough got yet more explicit in 2020 with a film to which he lent significantly more than voiceover narration. For Netflix, Attenborough produced “A Life On Our Planet” as his “witness statement” after observing all corners of the Earth for decades. Then 93, Attenborough opens the film in Chernobyl, the remnants of a world ruined by man strewn all about him. “The natural world is fading,” he says directly to the camera, and to us, his rapt audience. “The evidence is all around. It’s happened in my lifetime: I’ve seen it with my own eyes.” Here, Attenborough also distills his worldview and mission into a succinct sentence that encapsulates his every recent project: “[This is] the story of how we came to make our greatest mistake — and how, if we act now, we can yet put it right.”

Having spent much of his lifetime coming to this conclusion, Attenborough has made himself an unparalleled authority on the most pressing issue of climate change. Perhaps more importantly, he’s made himself an approachable, trustworthy voice of reason in a debate that too frequently gets lost in hysterical denial of the facts. Many people may tune in to a show featuring Attenborough simply because his gentle voice provides both comfort and a guarantee of quality. And even if they’re not looking for lessons on the values of conservation, Attenborough has found a way of delivering them with patience, gravity and an undeniable expertise that makes him impossible to ignore.