University of New Hampshire associate professor of Earth science Joe Licciardi, lead author of a new study in this week's Science, analyzed samples from glacial moraines on the slopes of Nevado Salcantay, a 20,000-foot-plus peak that is the highest in the Cordillera Vilcabamba range of southern Peru.
(PhysOrg.com) -- A new study that reports precise ages for glacial moraines in southern Peru links climate swings in the tropics to those of Europe and North America during the Little Ice Age approximately 150 to 350 years ago. The study, published this week in the journal Science, "brings us one step closer to understanding global-scale patterns of glacier activity and climate during the Little Ice Age," says lead author Joe Licciardi, associate professor of Earth sciences at the University of New Hampshire. "The more we know about our recent climate past, the better we can understand our modern and future climate."
The study, "Holocene glacier fluctuations in the Peruvian Andes indicate northern climate linkages," was borne of a convergence of a methodological breakthrough in geochronological techniques and Licciardi's chance encounter with well-preserved glacial moraines in Peru.
On vacation in 2003, Licciardi was hiking near the well-known Inca Trail when he noticed massive, well-preserved glacial moraines - ridges of dirt and rocks left behind when glaciers recede -- along the way, about 25 kilometers from the ruins of Machu Picchu. "They very clearly mark the outlines of formerly expanded valley glaciers at various distinct times in the recent past," he says. But Licciardi, who had no geologic tools with him at the time, did not take any samples.