This review appeared in the Times Literary Supplement on 25 July 2008
Érik Orsenna, Portrait of the Gulf Stream: In praise of Currents, Translated by Moishe Black, 320pp., Haus Publishing. £18.00
Among the many irritations suffered by the British during their administration of the American colonies was the fact that ships dispatched from England took two weeks longer to cross the Atlantic than ships dispatched from America. At a loss to account for this disparity, the Admiralty eventually approached Benjamin Franklin, scientist and Postmaster General to the Colonies, whose subsequent enquiries among his seafaring contacts revealed what Nantucket whalers had known for generations: the existence of a swift Atlantic current that plies its way along the eastern seaboard before heading across the open sea to Europe. Franklin, whose next two crossings were spent excitedly testing the waters, confirmed that a fast-flowing ocean river, known as the Gulf Stream, did indeed run across the north Atlantic, and that “a stranger may know when he is in it, by the warmth of the water, which is much greater than that of the water on each side of it.”
In the centuries since Franklin’s findings, the course and pace of the Gulf Stream have been comprehensively tracked and measured, as have the changes that it undergoes during its long Atlantic crossing: as the current heads north, its cargo of warm tropical water cools and evaporates, leaving saltier, heavier water behind. By the time it reaches the Norwegian Sea the Gulf Stream’s payload is cold and dense enough to start sinking towards the ocean floor, turning to flow south towards the equator in a cold counter-current that will eventually return it to the point where its journey began. The effect of this great circulation is to transfer significant amounts of heat across the North Atlantic — a thermal budget almost 100 times greater than world energy demand — preserving the inhabitants of western Europe from the harsh winters which besiege other places at similar latitudes, such as Canada or southern Alaska.
This thermohaline warming was first described in the 1850s by the American hydrographer Matthew Fontaine Maury, who seemed to view the oceans as little more than a vast and efficient boiler house: “the furnace is the torrid zone; the Mexican Gulf and Caribbean Sea are the caldrons; the Gulf Stream is the conducting pipe”, he wrote, introducing an analogy that, along with his contention that “it is the influence of this stream upon climate that makes Erin the ‘Emerald Isle of the Sea’, and that clothes the shores of Albion in evergreen robes”, has proved surprisingly prevalent. “Now don’t forget to thank the Gulf Stream”, as Érik Orsenna’s grandmother would remind him as he shivered beneath his blanket during out-of-season holidays on the Breton coast; “if not for the Gulf Stream, our ocean would be cold”. Family prayers, according to Orsenna, were offered up to God and the Gulf Stream, the two great benefactors of Breton life, and “one of the pillars of my existence, one of the few axioms on which I could always count for support.” Thus began Orsenna’s lifelong love of ocean currents, and from an early age he began to “collect” them, “as others do with stamps or butterflies”, taking to the seas in a variety of craft, becoming in time one of France’s best-known mariners, as well as one of its most celebrated writers (his novel L’Exposition coloniale won the 1988 Prix Goncourt); and in all this time, Orsenna recalls, “the Gulf Stream has never left me.”
But in recent years a growing unease over the long-term future of the current has emerged, linked to the effects of global warming on diminishing Arctic sea ice. Rapid melting has already diluted the salty waters of the North Atlantic, but the fear among oceanographers is that a massive influx of cold, fresh water could weaken the Gulf Stream to such an extent that it would no longer sink in the Norwegian Sea, thus switching off the transatlantic heat conveyor. Northern Europe would consequently freeze, and this apparent paradox — that global warming could bring about a new European ice age — seems to have caught the popular imagination, adding the dramatic shutdown of the North Atlantic current to the now familiar catalogue of climate change catastrophe. However, scientific opinion remains divided over how likely or even possible such an outcome could be, leaving non-specialists such as Orsenna — “I am not a scientist. I am a wanderer”, he writes — uncertain what to believe. So, on the basis that the best way to learn about something is to start writing a book about it, Orsenna began telephoning oceanographers, asking for their guidance through the difficult terrain of ocean conveyors and temperature differentials, while learning not to ask unanswerable questions such as “where exactly does the Gulf Stream begin?” — the response to which was usually prefaced with a weary “it’s not that simple.”
Orsenna’s accounts of these conversations reveal the novelist’s dawning remorse for his lack of scientific awareness: “What a fool I’ve been to neglect science all these years”, he declares; “natural history is the mother of every form of history, every sort of story, the novel of all novels.” Like W. H. Auden, who said that the company of scientists made him feel like a shabby curate who had wandered by mistake into a drawing room full of dukes, Orsenna is a little in awe of the experts he encounters, not least because he begins to suspect that they are in possession of all the best stories. Like the ancient myths and legends of the sea to which Orsenna is clearly devoted, the great oceanographic narratives have much to teach us “about the nature of pathways and the secret of first beginnings”. The Gulf Stream, he soon discovers, is not so much a single path as a sequence of thermal improvisations: eddies, whirlpools, vortices, maelstroms. These scientific songlines of the sea “stir jealousy in a novelist’s heart”, and Orsenna brilliantly exploits the tension that arises between the two competing narrative modes — “I went endlessly back and forth from reading maps to reading legends, not knowing which would leave me better informed” — a process that in the end produces a near-seamless blend of travel, science and literary reportage, a peerless portrait of a force of nature made up of a series of digressions.