U.N.'s Ban says global warming is 'an emergency'

EDUARDO FREI BASE, Antarctica (Reuters) - With prehistoric Antarctic ice sheets melting beneath his feet, U.N. Secretary General Ban Ki-moon called for urgent political action to tackle global warming. 

The Antarctic Peninsula has warmed faster than anywhere else on Earth in the last 50 years, making the continent a fitting destination for Ban, who has made climate change a priority since he took office earlier this year.