In news on climate change, rapidly melting ice sheets in Greenland may unearth hazardous radioactive waste stored at a secret Cold War-era U.S. military base. The U.S. deposited the waste in deep underground tunnels at Camp Century in northern Greenland in the 1960s, expecting it would be secure underneath the ice forever. But a new study published in the journal Geophysical Research Letters says rapidly warming temperatures may now unearth the dangerous waste as soon as the end of this century, threatening local ecosystems.