It's all been happening in the Antarctic this week. First a huge iceberg 9 times the size of Singapore broke away into the sea. Then the Larsen B ice shelf, which had been floating on the sea for at least 2000 years, collapsed into thousands of icebergs. It must have been very dramatic, because within a month, an area of ice about the size of Cambridgeshire collapsed, creating 500 billion tonnes of icebergs. Neither of these events will make any difference to global sea levels. They could even be part of the natural cycle of events Antarctica. But there has been much speculation that the collapse of the ice shelf was prompted by global warming. The region of the Antarctic where it was located has experienced the most rapid warming of anywhere else on earth over the past 50 years.