Midway through our meeting at a sidewalk table of Brooklyn Public House in the Fort Greene neighborhood of Brooklyn, the Indian writer Amitav Ghosh lowers his voice, bemused. “Ejay dakho,” he says, “bangali,” nodding toward a man latching his bike to a pole and speaking on a cell phone. “See, a Bengali.”

We’d been talking about migration, one of the preoccupations of Ghosh’s most recent novel Gun Island. The book’s narrator travels to Venice and finds a city full of Bangladeshi migrants, the Bengali language echoing from scaffolds and through piazzas. In Brooklyn, too, where Ghosh has lived since the 1990s, those voices are growing louder. New York City’s population of Bangladeshis tripled between 2000 and 2015 to over 77,000 people, concentrated mostly in Queens and Brooklyn. “If I’m working in my study with the windows open, I can hear Bengali in the street,” he tells me later. “It’s completely a feature of life here.”

Over four decades of fiction and nonfiction, the Kolkata-born Ghosh has often traversed worlds that were once far apart. His first work of nonfiction, In an Antique Land (1992), conjured medieval traders and slaves drifting between India and Egypt. The sprawling Ibis trilogy, a set of novels that concluded in 2015, imagines Britain’s early-19th-century opium trade and the export of indentured labor from South Asia to distant colonies.

His most recent work has found other stakes, grappling with the immense challenge of climate change and asking questions about what novels can and should do as humanity speeds toward catastrophe. The Great Derangement (2016), a series of meditations on climate change and literature, argued that in centering individual subjectivity, realist novels are growing out of touch with a tumultuous, uncanny planet. “We have entered a time when the wild has become the norm,” Ghosh wrote. “If certain literary forms are unable to negotiate these torrents, then they will have failed—and their failures will have to be counted as an aspect of the broader imaginative and cultural failure that lies at the heart of the climate crisis.”

Gun Island, his ninth novel, poses one answer to how fiction can rise to the task of representing current realities. Its narrator, Deen, a Brooklyn-based antiquarian from Kolkata, hops from floods in West Bengal to Los Angeles plagued by wildfires to Venice sinking into the sea, all while untangling the mystery of an old folktale. The book is full of freak weather, collapsing ecosystems, and displaced communities. But beneath the foreboding of climate disaster, Gun Island finds a smaller human scale in the shape of the migrant.

When we meet over glasses of wine—him Malbec, me an amiable Sauvignon Blanc—our conversation fixes on the great human displacements happening around the world. (In the interest of full disclosure, Ghosh and I are neighbors and friends; he shared an early draft of Gun Island with me, and I’m mentioned in the book’s acknowledgements.) Ghosh, 63, dresses all in black and sports a white goatee. Green taxis glide by on DeKalb Avenue. The drinkers at the neighboring table plunge into a basket of mozzarella sticks and onion rings, while red-cheeked picnickers drift from Fort Greene Park after taking in the last of the summer sun. Though Ghosh calls this comfortable neighborhood home, he spends considerable portions of the year in India and on the road.

Over several years of research for Gun Island, he visited migrant and refugee camps in Italy, where he interviewed people who had come to Europe from South Asia. Initially, he had wanted to find out to what extent climate change drove migration—a previous novel, The Hungry Tide (2004), sifted the changing landscape of the swampy delta on the border between India and Bangladesh known as the Sundarbans, from where two characters in Gun Island leave to go to Italy. But Ghosh discovered that there was no direct relationship between climate change and migration, that “if it is causal, it is causal in a very occluded and complicated way.”

In Italy, Ghosh met a Pakistani man displaced by the flood of the Jhelum River in 2014. The man told Ghosh that when such floods happened in the past, people would just shift to another town, to an uncle’s house, or somewhere else nearby. But “with our phones,” the man said, destinations further away seemed easier to reach. “We had access to networks, we knew how it was possible to go. So we decided… why don’t we just leave?”

“This is the curious thing,” Ghosh muses. “Certainly, if your island sinks, if you suffer from a mega-drought in the Sahel, you leave. But what technology has brought into being are these very long journeys. Journeys that were inconceivable before, but which now are the first things that you think of.”

Ghosh measures his words and is a generous listener, with the gracious habit of agreeing enthusiastically with you before turning the conversation down a more interesting path. But a polemical fire smolders beneath his gentle tone. He is exasperated by the way people in the West, especially in English-speaking societies, discuss migration.

“There are two important and interesting things about a lot of the stuff written about migration these days,” he begins equitably. “One is that it’s almost entirely written by Westerners who don’t know the languages.” Ghosh speaks both Bengali and Hindi (which is mutually intelligible with Urdu), and so talked at length with Bangladeshi and Pakistani migrants in Italy. “The second is that it’s almost all written from the point of view of policy, whether from the right or the left. Is this good? Is this bad? It relates to the politics of the moment. But if you see what’s happening close up, it’s not really possible to take those positions so simply.”

He finds unsurprising the dull, xenophobic rhetoric of far-right figures like the Italian politician Matteo Salvini. Liberals earn more of his scorn for misrepresenting the migrant crisis. “Liberal mythmaking has a lot to do with this problem,” he says. “For liberals, who is this good migrant, who is the acceptable migrant? It always has to be a victim. The reality is that migrants are often in their teens and 20s, they are people who have agency.”

In Gun Island, Deen meets a young man called Tipu in the wilds of the Sundarbans who speaks English in American slang, chats knowledgeably about places and cultures far from South Asia, and is technologically savvy and smartphone-adept. Eventually, Tipu leaves the Sundarbans and travels to Europe. He is an exemplar of the phenomenon that Ghosh is tracing: migrants who decide they want to leave home not just because they need to, but because they have seen through their screens tantalizing glimpses of another life.

Liberal moralizing finds no virtue in the desire of migrants to bring their labor back and forth across borders. Migrants have to be hounded by vicissitude and circumstance to be worthy of inclusion in our societies. “Even in the liberal mindset, people who have just come to work are not acceptable,” Ghosh says. “Why? You have to be a victim. It’s such a crazy idea.”

In truth, migrants are often victims of their own decisions. “Those migrants in Italy now, I can tell you, are miserable. They hate it, they curse themselves for having left,” Ghosh says. “These guys are living 10 to a room in Palermo, getting by on a few euros a day, washing windows and cars, eking out a truly miserable living. No matter how bad things may be in Bangladesh, at least you have the consolations of friendship and family and community.”

Though Ghosh is wary of generalization, he claims that the South Asians he met were not fundamentally interested in assimilation or making themselves Italian. “What the migrants really want is a situation where they can work in Italy maybe three months of the year and then go home. None of them want to be there forever.”

Ghosh reminds his readers that migrants are protagonists in full, deep narratives whose outlines appear only in vague contours in Western media. They don’t see themselves as victims of circumstance, but as agents of their own futures. “I asked so many of these guys, especially those who were clearly climate refugees, whether they would call themselves climate refugees. And not a single one would,” Ghosh shakes his head. What would they say instead? The writer smiles. “Kaam ke liye aaye hain”—“We came to work.”