Pyrenees ice caves melting, erasing millennia of climate data

Ice deposits in the Pyrenees caves, some dating back 4,000 to 5,000 years, are rapidly melting. This loss is destroying vital paleoclimate information, including records of ancient temperatures, precipitation, and plant genetic material.

Geology researcher Mario Bielsa, a doctoral student at the University of Zaragoza, reports that several caves have already lost nearly all their ice. In Monte Perdido, air temperatures inside a cave have risen from zero to four degrees Celsius in just two years, a change that makes maintaining ice deposits impossible.

While some areas have seen ice thickness decrease by two to three meters over the last two decades, Bielsa notes that all caves in the Pyrenees are currently losing ice. Researchers are now conducting urgent sampling campaigns to collect data before these unique environmental archives disappear entirely.