BBC World Service at 80: A lifetime of shortwave The BBC World
Service - which marks its 80th birthday on Wednesday - was
broadcast only on shortwave back in 1932. Today, audiences on
FM, digital radio and the internet are growing fast while
shortwave is in decline, but for millions it remains a lifeline.
Shortwave listeners catch a signal that travels thousands of
miles across international boundaries, sometimes eluding
censors, by bouncing off the turbulent gases of the ionosphere,
the layers of electrified gas several hundred kilometres above
the earth. It's a signal that can be capricious - subject to
interference from electrical storms and other atmospheric
disturbances and, mysteriously, often best at sunrise or sunset.
But even when heard against a background of electronic warbling,
whistling and hissing, shortwave has reliably delivered the news
for 80 years. Four listeners tell their stories. Robert
Mulvaney, glaciologist, Antarctic I am a glaciologist studying
climate change who works "in the field"