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Cyclones create an ice-free expanse of sea that opens regularly during the cold Antarctic winters.
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "Sea ice in Antarctic is the thickest in winter, the appearance of open water is therefore disconcerting. These open seas are called polynyas. In 2017, scientists spotted one in the Lazarev Sea, which they called Maud Rise's polynya, as it rests on an ocean shelf called Maud Rise. "Data-reactid =" 12 "> The Antarctic sea ice is the thickest in winter, the appearance of open water is a source of perplexity.These open seas are called polynyas. have spotted one in the sea of Lazarev, which they called Maud Rise's polynya, because it rests on an oceanic plateau called Maud Rise.
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "Now the researchers led by Diana Francis, a new A York University scientist in Abu Dhabi has discovered that cyclonic winds push ice in opposite directions, resulting in the opening of the sea ice and the exposure of the sea.[[[[Antarctica: the bottom of the world covered with ice (Photos)]"data-reactid =" 13 "> Researchers led by Diana Francis, an atmospheric scientist at New York University in Abu Dhabi, discover that cyclonic winds push ice in opposite directions, which leads to the opening of the pack ice and exposes the sea. [Antarctica: The Ice-Covered Bottom of the World (Photos)]
Polar storms
As of mid-September 2017, the Maud Rise Polynya was 9,500 square kilometers. By mid-October, it reached 800,000 km 2.
The polynya Maud Rise in September 2017. NASA Worldview
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "A high resolution satellite imagery analysis has The warm, humid air from the western South Atlantic hit cool, north-facing air from the south, paving the way for severe thunderstorms. cyclones ranked 11 on the scale of the Beaufort storm, which means that they involved winds up to 117 km / h and waves up to 16 meters (52 feet) ) high above the sea level. "data-reactid =" 27 "> An analysis of high-resolution satellite imagery explained this rapid growth: Warm, humid air from the west from the South Atlantic struck cold air heading north from the south, paving the way for severe storms.The resulting cyclones were rated at 11 on the Beaufort scale ., that is to say, they produce winds up to 117 km / h and waves up to 16 meters high, wherever they are on the high seas.
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "These swirling winds have pushed back the ice of the cyclonic centers, Francis and his colleagues wrote on April 24 in the newspaper JGR Atmospheres. "data-reactid =" 28 "> These swirling winds have pushed back the ice of cyclonic centers, wrote Francis and his colleagues on April 24 in the journal JGR Atmosphères.
Cyclones and climate
<p class = "canvas-atom-canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "Polynya is neither new nor necessarily harmful. National Snow and Ice Data Center (NSIDC), they can provide important access to the sea for Antarctic animals and a habitat for animals. phytoplankton. "data-reactid =" 30 "> Polynyas are neither new nor necessarily harmful, according to the National Snow and Ice Data Center (NSIDC), they can provide important ocean access for Antarctic animals and phytoplankton habitat.
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "However, polynyas can change in a warmer future, Francis and his colleagues have speculated that the Antarctic should experience stronger cyclones as the climate changes, as models show that storms may form more often towards the poles. and to be more intenseAccording to the NSIDC. "data-reactid =" 31 "> However, polynyas could change in the warmer future, speculated Francis and his colleagues.A Antarctica is expected to experience stronger cyclones as the climate changes, as models show that storms are likely to form more often towards the poles and be more intense, according to the NSIDC.
If these predictions are correct, Antarctica could see more open water in the coming winters.
<p class = "canvas-atom canvas-text Mb (1.0em) Mb (0) – sm Mt (0.8em) – sm" type = "text" content = "Originally posted on & nbsp;Science live"data-reactid =" 37 ">Originally published on Science live.
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