You don't automatically think "comic novel" when you think of Ian McEwan, although his previous, On Chesil Beach, was for the most part as funny as it was ghastly. But his latest, Solar, is the closest thing to a romp you can imagine him contriving.

Michael Beard is a mid-career scientist, a Nobel prizewinner, no less, for his work on the quantum mechanics of Einstein's photovoltaics, the science of how it is that light produces electricity when it plays upon a semiconductor. The so-called Einstein-Beard Conflation was produced during an extraordinary burst of creative thinking accomplished against the odds in his youth, when he was newly married to his first wife and sharing cramped quarters rendered noisy and noisome by their lodgers' grizzly, identical twin babies.

It's all been downhill from there. By the time we meet him in the year 2000, Beard is the figurehead director of a research centre that has been uselessly frittering away public money trying to develop a wind turbine for domestic applications. His ear is being bent by Tom Aldous, an earnest young post-grad who has a bee in his bonnet about artificial photosynthesis as the potential saviour of our warming world, but Beard is unable to get excited about it. His fifth marriage is collapsing due to his constant philandering. His wife is gadding about with the builder to get back at him for his latest affair.

Then things start to happen. Beard is invited to join a party of artists and writers who are going on a trip to the frozen Arctic island of Spitzbergen, to focus their creativity on the looming spectre of climate change. Upon his return, a freak accident befalls young Aldous, presenting Beard with an opportunity to put his marriage out of its misery, take revenge on the builder and launch himself on an entirely new and brilliant career direction, thanks to the fat folder of musings and calculations that Aldous has left behind, all in one fell swoop.
The novel describes two subsequent phases in his life. We see him in 2005 as the wholehearted convert to the cause of fighting human-induced global warming, addressing business leaders on the opportunities that the so-called "clean industrial revolution" present, even as he prepares to exploit those same opportunities himself.

He's in a new relationship, and staunchly resisting all pressure to make his sixth matrimonial mistake, even when his partner announces she has taken steps to get what she wants out of the relationship, whether he likes it or not. And we meet him again in 2009, on the eve of the "switching on" of his artificial photosynthesis power plant in New Mexico, as the pages grow dark with the wings of chickens, chickens coming home to roost.

There are some adroitly deployed symbols: the melanoma on Beard's hand that he is steadfastly ignoring, after the pattern of climate change denial; the treacherous polar bear skin rug that does for poor Aldous; the escalating portions of food that Beard consumes.

Solar is very funny - the Spitzbergen trip is hilarious, as is the intense duel over junk food fought by Beard and a fellow commuter on the underground, a Waste Land moment where McEwan shows us all the fear and loathing of the modern world in a packet of crisps.

But there's a darker, underlying message. Regardless of what you'll read, Solar isn't about climate change at all, although global warming and all the angst and debate around it is part of the setting. It's more of a good old-fashioned cautionary tale.

Michael Beard, greedy, self-interested and self-absorbed and opportunistic, oblivious to - or at least, heedless of - the damage he does, is an incandescent lampoon of the baby boomer generation. He's the personification of the deplorable side of human nature that has got us all into the pickle of climate change in the first place.

*Solar,Jonathan Cape $38.99.

John McCrystal is a Wellington reviewer.