The ice, poised between freezing and melting, is an especially sensitive indicator of the planet's temperature.

ECONOMIST: An imminent answer to an Arctic riddle

Gold, the most sensitive indicator of monetary turbulence, has fallen to levels not seen since the late 1970s.

FORBES: Fact and Comment

Scientists say that images from this region will provide a sensitive indicator of the onset of magnetic storm activity.

BBC: Atmosphere Nasa

The price of gold, the most sensitive indicator of inflation, remains low.

FORBES: How to Bomb the Boom