In 2012, sea ice melted to a record-breaking minimum extent. At the end of the summer melt season, ice covered only about half of the average area it did from 1979–2000.

Although most drifting buoys start their journeys with a crude send-off—usually heaved into the ocean from the stern of a moving ship—NOAA oceanographer Rick Lumpkin describes today's drifter as "a high-tech message in a bottle."  Insignificant on their own, but an army of drifters 1,000 strong patrols the world's oceans and records key data for climate monitoring and research.

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