If in late July, for whatever reason, some internet user found themselves in need of an in-depth review of the Sycamore tree and its definitive ranking on a scale from one to five stars, they might have come across a 24-minute piece of audio titled: “Air Conditioning and Sycamore Trees.”

As reviews go, this clip isn’t especially straightforward. It offers no judgements on leaf-shape or bark-feel, or whatever one might expect from the world of tree criticism. Instead, the audio involves a quiet, meandering monologue about children’s games, the Milwaukee airport, the pointlessness of living, and the eye-gouging nullity of gardening. (Gardening, the narrator intones, amounts merely to “inefficiently creating food that will sustain our useless vessels for a little while longer.”)

The Sycamore doesn’t come up until 20 minutes in. But when it does, the tree presents a feeble antidote to the narrator’s nihilism, the thing that makes him mutter, “My God, that’s a beautiful tree,” before admiring its age, size, and periodic mentions in the writings of George Washington and Persian emperor Xerxes. Just before the speech turns treacle, the narration cuts short: “I give sycamore trees four and a half stars.”

This recording is the latest episode of Anthropocene Reviewed, a deeply odd podcast from young adult author John Green, in which the Fault in Our Stars writer rates “different facets of the human-centered planet on a five-star scale.” It’s a review show where the subjects aren’t books or movies, but everyday miscellany in the Anthropocene, the current geological era which began when human activity became the dominant force affecting environment and climate. The podcast, which broadcasts from WNYC Studios on the fourth Thursday of every month, hasn’t attracted much critical attention outside its regular audience, in part because it’s hard to place. Each episode considers two topics—Canada Goose (three stars), Diet Dr. Pepper (4.5 stars), Cholera (one star)—blending memoir, history, literature, and the idiotic, but acutely familiar impulse to evaluate even the most inane objects, into the audio essay equivalent of a Yelp review.

If a listener knew of John Green only in passing, as I did, the notion of the writer sending monthly nihilistic missives on a grocery list of subjects might seem like a radical break from his repertoire. Green has made a name for himself publishing stories aimed at adolescents. His debut novel, Looking for Alaska, won the Printz Award in 2006, and after a slew of successful follow-ups—Paper Towns, An Abundance of Katherines, and The Fault in Our Stars—Green became something of a tween household brand. His books have spent weeks on the New York Times bestseller list, two were adapted into feature films, and in 2014, Time magazine named Green one of the “100 Most Influential” people in the world.

His novels, which all feature teens grappling with grief, romance and trauma for the first time, were edgier by YA standards, peppered with dark jokes, swearing, and explicit sex scenes. But they were also overtly earnest. “That was an age in fiction when there was a lot of emphasis on creating ironic distance between the big questions and the people asking them, ” Green told The Daily Beast. “I liked that. But I wanted to write in a way that didn’t have any distance between those big questions and the people asking them.”

The same might be said of Green’s other occupation, which has evolved into what the writer calls his “day job,” as a prolific YouTuber and online video producer. In 2007, Green teamed up with his younger brother, Hank, to start a channel called VlogBrothers. The siblings were both fans of the seminal YouTube series, the show with ze frank, whose host vlogged every day for a year, and the Greens' first project, Brotherhood 2.0, had a similar premise. For one year, neither brother texted, called or emailed one another, but spoke exclusively through vlogs. It was a plainly unserious and extremely dorky enterprise, filled with the jump cuts, gags, and mid-aughts modifiers of early internet video (“awesome” is a favorite refrain). But the project also represented a sincere effort at bonding for the brothers, whose teendoms had been somewhat separated by boarding school.

Like Green’s novels, the YouTube channel amassed a huge following. As of this article, the channel has more than 3.2 million subscribers and 1,735 videos, most with several hundred thousand views. It spawned a subculture called “Nerdfighteria,” whose followers call themselves “nerdfighters,” and who post in forums moderated by select devotees called “ningmasters.” Fans have their own hand signal (a riff on the Vulcan salute), produced their own line of Green-themed merchandise, and have fueled several of the brothers’ charity drives—including the Foundation to Decrease World Suck, and the annual Project for Awesome. After Brotherhood 2.0, the Greens went on to launch 11 other online series, including an education channel called Crash Course, whose science and arts courses have collectively garnered more than one billion views.

In some ways, Anthropocene Reviewed has roots in Green’s other projects. It was while on tour with his brother, for example, looking for a restaurant on Yelp, that the writer observed just how much of the world had been catalogued by at least one online critique. There are the obvious write-ups on books, food, and museums, but a cursory search of almost anything can turn up the screed of at least one disgruntled consumer, be it an airport, a municipal work installation, or a bus stop. (“This is somewhat of a rare item,” one Amazon user writes about an action figure of WWE wrestler Chris Benoit, who killed his wife and child in a murder-suicide. “But this is a terrible toy to give to any kid.”) There is even, Green pointed out, an extensive TripAdvisor exchange about the bench in Amsterdam where part of The Fault in Our Stars movie was shot.

And like both Green’s books and vlogs, the podcast does embrace a kind of earnestness. It’s filled with sincere accounts of personal histories, impassioned analyses of diet soda flavor profiles, and semi-straight-faced arguments about where his chosen subjects fall on a five-star scale.

Still, what makes Anthropocene Reviewed so bewildering is that it frames that sincerity with a wry, but totalizing cynicism. On this show, Green is clearly jaded—about humanity, capitalism, our ability to stave off climate-induced extinction. In that sense, it seems completely unlike anything else the author’s ever done. The voice of Anthropocene Reviewed is no YA character, encountering adult agonies for the first time. It’s a guy old enough to know them, expect them, and take them tongue-in-cheek. And within a premise both absurd and bluntly utilitarian, Green pulls off emotional soliloquies, historical digressions, and literary interludes without approaching cheesy or pretentious. His taunting checks his treacle, and vice versa. If the author’s novels dissolved the ironic distance between big questions and the people who ask them, his podcast reimagines what that distance might do. I give it four stars.