The finding comes after an international team of scientists, including Australian Antarctic Division physical scientist Dr Petra Heil, investigated the calving of a square kilometre, metre-thick iceberg off the Amery Ice Shelf in East Antarctica. The calving on 25 September occurred almost a decade earlier than scientists had expected based on historical observations , from an existing rift across the front of the ice shelf.
Two explosive cyclone events just prior to the calving, were caused by unusual atmospheric conditions that fuelled sustained cyclones at the front of the ice shelf, and helped direct moist, warm air towards the ice shelf at the same time. Dr Heil said these high latitude cyclones form in the extra-tropics, or mid-latitudes, and deepen as they move towards Antarctica.
They are marked by a deep central air pressure, are longer-lasting than ordinary cyclones, and bring clouds, high winds and often heavy precipitation. The team used satellite data and climate reanalysis using models to analyse historical atmospheric observations to understand the unusual atmospheric conditions at the time of the calving.
Antarctica is technically a desert, and a particularly dry one at that. This is because the cold air simply can't hold much water. There's no precipitation without humidity, and there's no humidity without heat.
You might be wondering why the continent is covered in snow if it rarely falls. Even though there isn't much precipitation per year, the temperatures don't rise high enough for the snow to melt away.
Anything that does fall gets accumulated until it's packed into ice. The dramatic elevation differences throughout Antarctica lead to impressive and harrowing wind speeds. The continent's coastal regions experience what's known as katabatic winds, or winds that that flow down slopes to the areas below. Although that's the average, the air can - and does - move a whole lot quicker.
Covid Updated information. Expeditions Go to Norwegian Coastal Express. Go to Hurtigruten Group. Weather and seasons in Antarctica Dramatic seasons, harsh temperatures and impressive winds all help make the South Pole one of the most interesting weather locations on Earth. Here's an overview of what weather conditions are like on Earth's southernmost destination: Seasons in Antarctica Antarctica only has two seasons: summer and winter.
Polar packing: What to bring on your trip to Antarctica? What whales might you see? What about penguins? Why go during this season? White sea ice and snow reflect sunlight back to space. When they melt - as they have been globally, from glaciers to floating ice - more of that solar radiation is absorbed in the dark oceans, such as those surrounding Antarctica.
The extent of sea ice at both polar regions at the start of remains close to record low levels. Antarctica posted both a record-low sea-ice extent in and its lowest average coverage of about Dr Lieser is helping lead the southern version of the Sea Ice Prediction Network aimed at forecasting sea-ice changes, echoing a service that has been operating for the Arctic for the past decade.
The first co-ordinated forecasts for the summer retreat of Antarctic ice should be available next month, he said. Improved sea-ice forecasts will help scientists hone their seasonal and longer-term forecasts, with particular benefits for southern hemisphere nations such as Australia.
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