The Acoustic Thermometry of Ocean Climate project will unplug and remove its transmitter off the California coast at the end of the year. A second transmitter, off Hawaii, will operate through the end of 1999 before getting pulled from the water. Researchers say they don't have the money. They also appear weary, and wary, of the effort needed to obtain another round of permits. Then listen for the sound thousands of miles away.
Sound travels faster in warmer water, slower in cooler water.
By measuring the time between when a sound is made and when it's heard, scientists can determine the average water temperature along the sound's path. A few months before the transmitters were to be installed in 1994, the project became a topic on a marine mammal forum on the Internet. The resulting maelstrom stirred up the media and Congress. The power of the Internet has a very dangerous side. Part of the problem was a misunderstanding of how loud the speakers are.