Antarctic Region the Size of California Melted in '05

"Antarctica has shown little to no warming in the recent past with the exception of the Antarctic Peninsula, but now large regions are showing the first signs of the impacts of warming as interpreted by this satellite analysis," said Konrad Steffen, director of Boulder's Cooperative Institute for Research in Environmental Sciences, in a statement.

The warm spell did not last long enough for the meltwater to flow into the ocean, the researchers noted.

But a longer melt of such severity could create enough water to seep beneath Antarctic ice sheets and send them sliding into the sea, they added.