A new novel by Ian McEwan, which is set nearly a century in the future in a UK partly submerged by rising seas, will come out later this year.

What We Can Know is “science fiction without the science”, said McEwan. “My ambition in this novel was to let the past, present and future address each other across the barriers of time.”

The novel is a “deeply humane” work that “defies categorisation” according to its publisher Jonathan Cape, an imprint of Penguin Random House.

Set in 2119, the novel imagines a Britain that has become an archipelago, after the country’s lowlands were submerged by rising tides. It follows Tom Metcalfe, an academic at the fictional University of the South Downs.

Searching in the archives, Tom comes across a clue that may lead to a lost poem, read aloud in 2014 and never heard again. His find reveals a story of entangled loves and a crime that destroys his assumptions about people he thought he knew well.

“This is a novel about history, and what we can know of it, and of each other,” said McEwan. “We live our lives between the dead and the yet to be born. Of the dead we know a little, but not as much as we think. About the present, we disagree fiercely. People of the future are beyond our reckoning, but we’re troubled by what we’ll bequeath them. As they look back at us, what will our descendants think, when they contemplate the diminished world we left them? They might envy us.”

“To catch at these thoughts, I’ve written a novel about a quest, a crime, revenge, fame, a tangled love affair, mental illness, love of nature and poetry, and how, through all natural and self-inflicted catastrophes, we have the knack of surviving somehow,” he added.

McEwan has published 17 novels including Atonement, Enduring Love, On Chesil Beach and, most recently, Lessons, described as “compassionate and gentle” and “a tale of humane grace” by Beejay Silcox in the Guardian. In 1998, McEwan won the Booker prize with his novel Amsterdam. He is also the author of two short story collections, First Love, Last Rites, which won the Somerset Maugham award, and In Between the Sheets.