Credit: Chris Buzelli

The driver turned off the engine of his rumbling Russian- army troop carrier at the edge of a deep canyon carved by a stream of glacial meltwater. Our little research group--which included Stanford graduate students Jamie and Meaghan, postdocs Jan and Jake from the Carnegie Institution of Washington, and our guide, Vladimir--clambered down from the truck for a welcome stretch after a jarring five-hour drive from Petropavlovsk. Then we shouldered our packs and began to climb, crunching over packed snow and ice between house-size boulders. When we stopped for breath and looked back downhill, we could see the ash and lava flows from past eruptions eroded into hills and valleys, with scattered patches of low shrubs in sheltered areas far below. The jagged volcanic landscape of Kamchatka defined the horizon. Above us loomed our goal: the blasted peak of Mount Mutnowski, a volcano that had erupted just a few years before.

Select from the choices above to read the entire article.