A few years before he died in 1992, Henry Stommel sketched a vision of the future of oceanography. It makes poignant reading now. Stommel was the man who had figured out why there is a Gulf Stream. He had helped establish the basic theory for how ocean currents work. In the process he had received every prize and accolade he possibly could. But in his little essay in the magazine Oceanography, Stommel imagined giving up all that. He pictured himself in the twenty-first century, looking back from middle age on a second youth and a second career that was just getting started in 1996. It was a career that had been transformed by a single invention.
Stommel’s first career, like that of all oceanographers, had been plagued by one problem above all: a lack of good data. Compared with the means they have to study it, the ocean is too big, and it changes too fast. Meteorologists have it much better: they drown in data every day. Their thermometers and barometers are everywhere on land; satellites tell them when the next hurricane is coming; and twice a day without fail, at around noon and midnight Greenwich time, they let fly more than 800 helium balloons from stations around the planet. Rising through the atmosphere, those balloons radio back the temperatures, pressures, and wind speeds they encounter before they burst about 20 miles up.
Pity the oceanographer, though, who wants to know what the water is like somewhere deep inside the ocean--the better to understand how currents transport heat around the globe; the better, ultimately, to un- derstand how our climate is likely to change over the long haul. He must set sail with a ship and a crew of dozens. The simple act of sticking a thermometer in the middle of the Pacific costs him, or rather his government, hundreds of thousands of dollars. Steaming across the ocean in a straight line, he stops every so often to repeat the same routine measurement at stations no oceanographer is likely to visit again for decades. It is tedious, expensive work--and it isn’t done nearly often enough.
So Stommel imagined a machine that could do it. It would be the oceanographic equivalent of those helium balloons, only better. It would be a small, cheap, torpedolike drone that would glide around in the ocean on its own, with an ingenious new engine that would draw power not from batteries but from the ocean itself. Stommel envisioned a thousand of these robots porpoising through the sea at once, staying out for five years and collecting data with a few simple sensors. And several times a day each one of them would broach the surface to report via satellite to Mission Control.
That is where Stommel would sit: on an unspoiled island off Cape Cod, not far from the Woods Hole Oceanographic Institution, where he had spent most of his first career. The island was to be a kind of sanctuary. It would have few permanent residents and no automobiles--just a narrow- gauge railway, like the one Stommel had once built in his own yard to amuse his grandchildren and himself. Outside the headquarters building, sheep would graze on the grass bank that sloped down to the sea; inside, virtual- reality displays would immerse oceanographers in the latest data from the scattered robot fleet. In Stommel’s vision, twenty-first-century technology coexisted peacefully with the shade of Henry David Thoreau.
