Global ocean levels have risen by 4 to 10 inches over the past
100 years. How much more will they rise in 10 years? What about
in 50? This kind of question is critical for planning future
coastal development, but taking the measurements necessary to
make predictions can be difficult and downright risky for human
surveyors, who could be smashed by falling chunks of ice the
size of the Empire State Building. So send in a bot, says David
Holland, an oceanographer at New York University, who teamed up
with the National Research Council of Canada (NRC) to deploy a
five-foot-long autonomous submarine beneath an iceberg off the
coast of Greenland. Called the Slocum underwater glider, the sub
propels itself through water with a single-stroke piston,
thereby conserving most of its energy for data collection.
Sensors under the port-side wing measure conductivity (to find
the salinity of the water), temperature, and depth, sending the
data to processors within the sub. Icebergs are difficult to
navigate, even for a soph