Polar bears are the draw for most visitors to Spitsbergen, the largest island in Norway's Svalbard archipelago. For geoscientist Lee R. Kump of The Pennsylvania State University, however, rocks were the allure. In the summer of 2007 Kump flew to this remote Arctic Ocean island to find rocks that might offer fresh insights about one of Earth's ancient episodes of global warming: the so-called Paleocene–Eocene Thermal Maximum, or PETM. In that event, some 56 million years ago, global temperatures rose 5 degrees Celsius in the course of a few thousand years—a mere instant in geologic time.

This slide show features highlights of Kump's Arctic quest to find those rocks