China’s Growth Fuels Boom in World Shipping Traffic
Satellite data show numbers quadrupled over two decades, raising new concerns about escalating emissions.
Ship traffic on the world's oceans has quadrupled over the past two decades, according to a new study that's the first to rely on satellite data to produce global maps of shipping on the open seas.
The data for the study, which was published on November 17 in Geophysical Research Letters, came from a series of satellites that carried radar altimeters, devices that measure the height of the sea's surface at a given location by bouncing a radar beam off it. The data had been used primarily to measure sea-level rise, ocean currents, and even the topography of the ocean floor. But the radar echoes can also pinpoint the location of icebergs—and ships.
"As we processed all the archives of the
