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How are rocks formed ? Polar vortex. The polar vortex The typical polar vortex configuration in November, 2013... ...A wavy polar vortex on January 5, 2014. Polar vortex over Quebec and Maine on the morning of January 21, 1985 A polar vortex is a persistent, large-scale cyclone located near either of a planet's geographical poles. The Northern Hemisphere vortex often has two centers, one near Baffin Island and the other over northeast Siberia.[2] The Antarctic vortex in the Southern Hemisphere tends to be located near the edge of the Ross ice shelf near 160 west longitude.[3] When the polar vortex is strong, the Westerlies increase in strength.

History[edit] The polar vortex was first described as early as 1853.[5] The phenomenon's sudden stratospheric warming (SSW) appears during the wintertime in the Northern Hemisphere and was discovered in 1952 with radiosonde observations at altitudes higher than 20 km.[6] Identification[edit] Polar cyclones are climatological features that hover near the poles year-round. See also[edit] 5 Scary Effects Of Climate Change That Could Happen In Your Lifetime. It Was So Cold in Canada, the Ground Exploded. Impact on the poorest. Climatology. Real-Time Lightning Map. Global Warming Literature. Meteoalarm - severe weather warnings for Europe - Mainpage. National and Local Weather Forecast, Hurricane, Radar and Report. Acceleration of snow melt in an Antarctic Peninsula ice core during the twentieth century : Nature Geoscience.

Over the past 50 years, warming of the Antarctic Peninsula has been accompanied by accelerating glacier mass loss and the retreat and collapse of ice shelves. A key driver of ice loss is summer melting; however, it is not usually possible to specifically reconstruct the summer conditions that are critical for determining ice melt in Antarctic. Here we reconstruct changes in ice-melt intensity and mean temperature on the northern Antarctic Peninsula since AD 1000 based on the identification of visible melt layers in the James Ross Island ice core and local mean annual temperature estimates from the deuterium content of the ice.

During the past millennium, the coolest conditions and lowest melt occurred from about AD 1410 to 1460, when mean temperature was 1.6 °C lower than that of 1981–2000. Since the late 1400s, there has been a nearly tenfold increase in melt intensity from 0.5 to 4.9%. View full text Figures. Antarctic ice melting 10 times faster than 600 years ago. Updated Mon 15 Apr 2013, 11:10am AEST A report has found that the Antarctic summer ice melt is now occurring 10 times faster than it did 600 years ago. Scientists from the British Antarctic Survey and the Australian National University drilled a 360-metre ice core near the northern tip of the peninsula to to identify past temperatures. The ice core gave an extraordinary insight into the temperatures, revealing the coolest conditions, and the lowest melt, occurred six centuries ago.

By comparison, it found temperatures now are 1.6 degrees Celsius higher, and the ice melt is 10 times as fast. The lead author of the report, Dr Nerilie Abram from the Australian National University, says the most rapid melt has occurred in the last 50 years. "The lowest levels of melt were about 600 years ago and then the melt has increased almost tenfold over that time," she said. "But it's really in the last 50 years or so that melt has increased dramatically.

Cyclones. Polar vortex. Polar Vortex sweeps south as 'life-threatening' cold hits US - live coverage | World news. How frigid 'polar vortex' could be result of global warming (+video) A bitter Arctic blast spanning the central and eastern US has propelled the phrase "polar vortex" from the pages of dense scientific papers to headline status as frigid temperatures and strong winds close schools and businesses and prompt forecasters to warn of "historic and life-threatening" conditions.

Skip to next paragraph Subscribe Today to the Monitor Click Here for your FREE 30 DAYS ofThe Christian Science MonitorWeekly Digital Edition In essence, a buildup of Arctic air, its chill deepened by 24 hours of darkness during winter, has breached its meteorological fence to pour deep into North America. Such outbreaks often involve tendrils of cold air that can leak through the fence. Paradoxically, the event may be a harbinger of winter outbreaks to come in the northern hemisphere as Earth's climate warms, some researchers say – a result of shrinking Arctic Ocean summer sea ice and the projected changes in wind and snowfall patterns triggered by the ocean's warmth and moisture.

Antarctica A ‘Key Driver’ Of Global Climate, South Pole Temperatures Affect ‘Rest Of The Planet’ In Minnesota, schools were closed for the first time in 17 years as winter temperatures sank to as low as minus 30 degrees Fahrenheit. "A person not properly dressed could die easily in those conditions," said Scott Trueett, a meteorologist for the National Weather Service. It’s turning out to be a painfully cold winter, colder in many cities than it has been in decades, and many are wondering why. Where are these extreme temperatures coming from? And what’s to be expected? "Antarctica is one of the key drivers of the global climate system," Tony Press, head of the Antarctic Climate & Ecosystems Co-operative Research Centre in Hobart, Australia, told The Sydney Morning Herald.

Every year, Antarctica’s ice shrinks in the summer and expands in the winter. But every year, a little bit less of the ice refreezes during the winter. Future research into Antarctic sea ice melt will focus on the thickness of the ice around the edges of Antarctica and the effect of ice melt on global sea levels. Polar vortex. Climate - Weather - Extreme. Information on Hurricanes and Tropical Storms for young people. Hurricanes and Tropical Storms Introduction A Hurricane, like other natural disasters, is one that we all pause to listen to each time we hear of it on the news. This is because we have all seen the devastation that it can bring to us. Many people have experienced it in one way or the other, and we have come to appreciate that hurricanes are not things that we can do much about in terms of its occurrence.

It is natural. However, with modern monitoring systems and technology, we can be warned of impending hurricanes and take some reasonable level of caution to minimize the damage and the effect it can have on us. Hurricanes are also called Typhoons or Cyclones in other parts of the world. What is a hurricane? It is a powerful, spiral weather that result from low pressure systems. Low Pressure SystemThis is an area (over land or water) where the atmospheric pressure is lower than that of the area surrounding it.

With this image in mind, let us learn more about hurricanes form. Weather Wiz. Thunderstorms What is a thunderstorm? A thunderstorm is a storm with lightning and thunder. Its produced by a cumulonimbus cloud, usually producing gusty winds, heavy rain and sometimes hail. What causes a thunderstorm? The basic ingredients used to make a thunderstorm are moisture, unstable air and lift. You need moisture to form clouds and rain. You need unstable air that is relatively warm and can rise rapidly. Finally, you need lift. When are thunderstorms most likely to occur? How many thunderstorms are there every day?

What is lightning? What causes lightning? Have you ever rubbed your feet across carpet and then touched a metal door handle? Click Here to see where lightning is currently striking across the U.S.What causes thunder? How far away can you see lightning and hear thunder? What is hail? What causes the wind to blow? What is a gust front? Know the Lingo Know the Facts The typical thunderstorm is 15 miles in diameter and lasts an average of 30 minutes. Thunderstorm Safety Tips.