Sounding out sea temperature

日期:2017-10-20 01:50:08 作者:司城尾 阅读:

By Bob Holmes in San Francisco A CONTROVERSIAL experiment that uses sound to take the sea’s temperature is working better than expected, say scientists who have analysed data from the first 15 months of the project. The Acoustic Thermometry of Ocean Climate (ATOC) experiment measures how long sound takes to travel from a loudspeaker off the coast of California to a series of microphones across the Pacific Ocean. Warm water transmits sound faster, so the elapsed time gives an accurate measure of the average temperature of the ocean. The scientists’ calculations had suggested that the experiment should work up to a range of 3000 kilometres. “In fact, these techniques work well up to at least 5000 kilometres,” says Peter Worcester of the Scripps Institution of Oceanography in La Jolla, California. As a result, Worcester and his colleagues have been able to estimate ocean temperature to within 0.006 °C (Science, vol 281, p 1327). That means ATOC should be a sensitive detector of global warming,