When Mike Poland arrived three months late for his post at the Hawaiian
Volcano Observatory, the 30-year-old had a doozy of an excuse: Mount
St. Helens, where he'd been stationed, started bellowing steam and ash
just before his December 2004 transfer. A volcanic deformation
specialist with the U.S. Geological Survey, Poland uses mapping-grade
GPS units precise to within a few millimeters — 1000 times more
accurate than recreational models — to analyze surface changes and
gauge activity in magma chambers underground. "By measuring ground
movement," he says, "we see signs if a volcano is working toward
erupting."
