VOLCANOES drop heavy hints before they erupt. For one thing they rumble and
start to bulge as molten rock rises up from below. You’d think then, with all
our seismographs and Earth-observing satellites, that pinpointing the time of an
eruption would be a cinch? “Not necessarily” is the resounding answer. The
eruption in the Congo last month was a grave reminder that these angry giants
can still surprise us.
In theory, researchers know what pre-eruption signals to look for
(see Â鶹´«Ã½, 12 January, p 28).
The trouble is watching one volcano won’t tell us
how another will behave.…
