(New York Times) - Antarctica has long resisted most effects of Global Warming. But now satellite analysis reveals that during one week in 2005 unusually warm air caused surface snow to melt over an area described as “California-size”.

While melt zones of this type have been seen in Antarctica before they are rare this close to the South Pole. And some of the melting this time around was at unusually high altitudes.

Scientists caution that it’s too early to tell whether the incident is a fluke, or the beginning of a new trend.

Read more from the New York Times (free registration may be required)