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Why do we still not trust the weather forecast?

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A 1971 television forecast gives American viewers the big picture
A 1971 television forecast gives American viewers the big picture Credit: H Armstrong Roberts

Simon Ings reviews The Weather Machine by Andrew Blum

Reading New York journalist Andrew Blum’s new book has cured me of a foppish and annoying habit. I no longer dangle an umbrella off my arm on sunny days, tripping up my fellow commuters before (inevitably) mislaying the bloody thing on the train to Coulsdon Town. Very late, and to my considerable embarrassment, I have discovered just how reliable the weather forecast is.

My thoroughly English prejudice against the dark art of weather prediction was already set by the time the European Centre for Medium-Range Weather Forecasts opened in Reading in 1979. Back then, Blum tells us, the ECMWF claimed to be able to see three days into the future. Six years later it could see five days ahead. It knew about Sandy, the deadliest hurricane of 2012, eight days in advance of its arrival, and it expects to predict high-impact events a fortnight before they happen by the year 2025.

The ECMWF is a world leader, but it’s not an outlier. Look at the figures: weather forecasts have been getting consistently better for 40 straight years. Blum reckons this makes the current global complex of machines, systems, networks and acronyms (and there are lots of acronyms) “a high point of science and technology’s aspirations for society”.

He knows, however, that this is a minority view. “The weather machine is a wonder we treat as a banality,” he writes: “a tool that we haven’t yet learned to trust.” This book is his attempt to convey the technical brilliance and political significance of an achievement that hides in plain sight.

Hurricane Irma sweeps across the Caribbean Sea in September 2017 Credit: NOAA via Getty Images

The machine’s complexity alone is off all familiar charts, and sets Blum a significant challenge. “As a rocket scientist at the Jet Propulsion Laboratory put it to me… landing a spacecraft on Mars requires dealing with hundreds of variables,” he writes; “making a global atmospheric model requires hundreds of thousands.” Blum does an excellent job of describing how meteorological theory and observation were first stitched together, and why even today their relationship is a stormy one.

His story opens in heroic times, with Robert FitzRoy one of his more engaging heroes. FitzRoy is best remembered for captaining the HMS Beagle and weathering the puppyish enthusiasm of a young Charles Darwin. But his real claim to fame is as a meteorologist. He dreamt up the term “forecast”, turned observations into predictions that saved sailors’ lives, and foresaw with clarity what a new generation of naval observers would look like. Distributed in space and capable of communicating instantaneously with each other, they would be “as if an eye in space looked down on the whole North Atlantic”.

You can’t produce an accurate forecast from observation alone, however. You also need a theory of how the weather works. The Norwegian physicist Vilhelm Bjerknes came up with the first mathematical model of the weather: a set of seven interlinked partial differential equations that handled the fact that the atmosphere is a far from ideal fluid. Sadly, Bjerknes’s model couldn't yet predict anything – as he himself said, solutions to his equations “far exceed the means of today’s mathematical analysis”.

As Blum traces the evolution of our weather models, so we see the individual genius being replaced by systems of machine computation. In the observational realm, something similar happens: the heroic efforts of individual observers throw up trickles of insight that are soon subsumed in the torrent of data streaming from the orbiting artefacts of corporate and state engineering.

Lightning strikes the German city of Dresden last month Credit: Robert Michael/DPA

The American philosopher Timothy Morton dreamt up the term “hyperobject” for something too complex and numinous to be described in plain terms. Blum, whose earlier book was Tubes: Behind the Scenes at the Internet (2012), fancies his chances at explaining human-built hyperobjects in solid, clear language, without recourse to metaphor and poesy. In this book, for example, he recognises the close affinity of military and meteorological infrastructures (the staple of many a modish book on the surveillance state), but resists any suggestion that they are the same system.

His sobriety is impressive, given how easy it is to get drunk on this stuff. In October 1946, technicians at the White Sands Proving Ground in Nevada installed a camera in the nose cone of a captured V2 and, by launching it, yielded photographs of a quarter of the US – nearly a million square miles banded by clouds “stretching hundreds of miles in rows like streets”. Today’s global weather system has not only benefited from military advancements in satellite positioning and remote sensing; it has made those systems possible. Blum allows that “we learned to see the whole earth thanks to the technology built to destroy the whole earth”. But he avoids paranoia.

Indeed, he is much more impressed by the way countries at hammer and tongs with each other on the political stage nevertheless collaborated closely and well on a global weather infrastructure. Point four of John F Kennedy’s famous 1961 speech on “Urgent National Needs” called for “a satellite system for worldwide weather observation”, and it wasn’t just militarily useful American satellites he had in mind for the task.

In 1962, Harry Wexler of the US Weather Bureau worked with his Soviet counterpart Viktor Bugaev on a report proposing a “World Weather Watch”, and by 1963 there was, Blum finds, “a conscious effort by scientists – on both sides of the Iron Curtain, in all corners of the earth – to design an integrated and coordinated apparatus”. This is all the more remarkable for coming at a time when weather satellites were so expensive they could be justified only on national security grounds.

Blum’s book comes a little bit unstuck at the end. A final chapter that could easily have filled a third of the book is compressed into just a few pages’ hand-waving and special pleading, as he conjures up a vision of a future in which the free and global nature of weather information has ceased to be a given and the weather machine, that “last bastion of international cooperation”, has become just one more atomised ghost of a future that the colonial era once promised us.

Why end on such a minatory note? The answer, by no means obvious, is to be found in Reading. Today, 22 nations pay for the ECMWF’s maintenance of a pair of Cray supercomputers. The fastest in the world, these machines must be upgraded every two years. In the US, meanwhile, weather observations rely primarily on the health of four geostationary satellites, whose replacement, every decade or so, costs $11 billion (£8.75 billion). (America’s whole National Weather Service budget costs only around $1 billion.)

Blum leaves open the question of how an organisation built by nation-states, committed to open data and born of a global view, is supposed to work in a world where information lives on private platforms and travels across private networks – a world in which billions of tiny temperature and barometric sensors, “in smartphones, home devices, attached to buildings, buses or airliners”, are aggregated by the likes of Google, IBM or Amazon.

One thing is disconcertingly clear: Blum's weather machine, this marvel of continuing modernity, is also, truth be told, a dinosaur. It is ripe for disruption, of a sort that the world, grown so reliant on forecasting, could well do without.

The Weather Machine is published by Bodley Head at £16.99. To order your copy for £14.99, call 0844 871 1514 or visit the Telegraph Bookshop