Why the cold Arctic is so frequently "high fever"

Analysis released by the National Oceanic and Atmospheric Administration showed that temperatures rose sharply near the Arctic on February 10th, about 27 degrees Celsius above normal.
In addition to the unusual heating on the 10th, Greenland's northernmost ground monitoring station on February 8th, in just 12 hours, the temperature soared from -22C to 2C, as warm as in summer, with a temperature difference of 24C.
February 21st, the sudden heavy snow really excited the people of Beijing, the circle of friends have turned on the "sunshine" mode.
even wrote a poem: "Whether it is winter snow, or snow betrayed winter."
", it was noted that temperatures near the Arctic had recently soared by 27 degrees Celsius.
"This snow won't be caused by an Arctic 'fever', will it?" "There are netizens exclaiming.
is understandable because the Arctic suddenly warmed by 36C one night in late 2015.
the warming, many countries around the world turned on the "frozen" mode.
people's impression, the Arctic is a bitter cold place.
so cold in the Arctic, the Arctic frequently "high fever"? Why did the Arctic suddenly heat up by tens of degrees Celsius? Analysis released by the National Oceanic and Atmospheric Administration, the scourge of the North Atlantic cyclone, showed that temperatures were about 27 degrees Celsius above normal on February 10th, as temperatures warmed sharply near the Arctic.
In addition to the unusual heating on the 10th, Greenland's northernmost ground monitoring station on February 8th, in just 12 hours, the temperature soared from -22C to 2C, as warm as in summer, with a temperature difference of 24C. ban Haoran, technical director of the
's first science and technology division focused on commercial weather services, said the reason for the warming was similar to the one at the end of 2015, when a series of violent storms formed in the Atlantic Ocean, and the warm air currents at the front of the cyclone were raging, blowing over London, across islands in the Norwegian Sea, and across the North Pole.
the cold air of the polar regions was forced to retreat as warm air continued to pump into the North Pole.
" is that this North Atlantic cyclone is not so strong, so the heating flow to the North Pole is not as strong as last time, the heating range is not so large.
" Shortly after breaking through the freezing point, the temperature at the North Pole returned to normal levels.
to this, Ban Haoran explained that the earth's poles, ancient times is a bitter cold place.
Due to the low angle of solar radiation near the polar region, less heat, belongs to the cold source of the atmosphere, the air over the polar region can not be supplemented by heat, the formation of low-altitude cold and high pressure, high-altitude cold low pressure, high-altitude cooperation is a strong cold subsidon air flow, coupled with the role of the Earth's spin, thus forming a long-term vortex over the Arctic.
Its energy structure is deep and usually stable, although in some very rare conditions combined with the rapid warming of the ground caused by the invasion of warm air, but because the invasion of this warm air is not sustained, there is not enough follow-up energy to supplement.
, it will soon be backfilled by the original cold air system, thus returning to normal.
the Arctic's sudden rise in 2015 occurred in December, and this Arctic warming occurred in February, why is every Arctic warming concentrated in this time period? Ban Haoran explained that because this period belongs to the northern hemisphere winter, the northern hemisphere as a whole is colder, the Arctic vortex sphere of influence expanded, the external fluctuations intensified, relatively vulnerable to the heating flow interference, while other seasons the Arctic vortex range shrinks, less volatility, the overall stability, the heating flow has no opportunity.
" This is like a war, the force occupied a large area, it is easy to give the enemy the opportunity to see stitches, and the concentrated advantage of the force shrink defense, the enemy is not easy to enter.
," Ban said.
it normal to have a frequent "high fever" to 0C in the Arctic? Or is it related to the accelerated warming of sea ice, although the cause of the sudden warming in the Arctic has been found, but is it normal for temperatures to rise so much that they even reach more than 0C? In response, it is not uncommon for temperatures in the Arctic to plummet by more than a dozen degrees Celsius in a day, said Yu Cuijuan, an associate researcher in the Marine Climate Prediction Office at the National Marine Environment Prediction Center.
, for example, monitoring data show that on 28 January 2016, the temperature at an observatory near Greenland rose from -20.1C to -6.4C, and on 21 December 2015, the temperature at another observatory in Greenland soared from -37C to -22C.
but it's rare to rise above 0C at this point.
the past two years, the frequency of the Arctic has increased above 0C.
"Because quantitative observations of the Arctic have not been long and the sample size is too small to tell whether the two-year surge is a coincidence or the beginning of a trend, " he said.
," Ban said.
, this is related to the overall high winter temperatures and the accelerated warming of the Arctic.
According to the U.S. National Center for Environmental Forecasting (NCEP), temperatures in the central Arctic region in December 2016 and January 2017 were about 10C higher than in the same period of the year;
experts point out that the Arctic is not only warming, but also accelerating warming, which is twice the global average.
Arctic warming is known as the "Arctic amplification effect", which is caused by a variety of factors.
main reason for this is the melting of sea ice.
recent years, the area of Arctic sea ice has been decreasing year by year.
january, Arctic sea ice covered 13.38 million square kilometers, the lowest level for the same month in January since satellite records began in 1979, said Yu.
sea ice, which is highly reflective to sunlight, melts into dark water, which in turn causes the Arctic to absorb solar radiation and absorbs a lot of heat.
the effects of melting sea ice and rising Arctic temperatures, which has accelerated Arctic warming.
the South Pole "fever" like the North Pole? Heat capacity properties different "high fever" rare "low fever" constantly heard of the Arctic "fever", why rarely heard of the Antarctic "fever", the Antarctic will be like the North Pole such a sudden "high fever"? In this regard, Ban Haoran said, compared to the North Pole, the Antarctic is farther away from human settlements, observation stations are not as large as the Arctic region, the overall observation time is not as long as the Arctic region, from the observation sample size is far less than the North Pole;
, Antarctica is still very low and the Antarctic glacier is unlikely to melt in a short period of time, so it won't heat up as fast as Greenland, " he said.
," said Tony Pres, Ph.D., of the Antarctic Climate Research Center.
that although the Antarctic is not easy to burst "high fever" like the North Pole, but it is not normal, has been "low fever."
U.S. study showed that between 1958 and 2010, the average temperature in the center of the West Antarctic ice sheet rose by 2.4 degrees Celsius, warming at nearly twice the rate previously predicted by scientists and three times the rate of global warming.
Monaghan, a scientist at the National Center for Atmospheric Research, said: "The results of the analysis show that the West Antarctic ice sheet has become one of the fastest melting ice sheets on Earth.
, in addition to rising temperatures, rising ocean temperatures around Antarctica are eroding the "body" of Antarctic glaciers, according to the British journal Science.
Antarctic glacier is the largest freshwater storage area on Earth.
these behemoths, which are several kilometers thick and stretch for thousands of kilometers, look quite strong and fragile.
B ice shelf, located in the northern Antarctic Peninsula, collapsed in just one month.
is 220 meters thick and covers an area equivalent to the entire downtown of Hangzhou.
by currents and sea breezes, the 50 trillion-ton ice drifts north and melts rapidly.
scientists say melting glaciers of more than 2.2 million cubic kilometers in the heart of the West Antarctic ice sheet could lead to a 3.3-meter rise in global sea levels.
, however, can be a long process that could take hundreds of years.
related links Why is Antarctica colder than the North Pole? Is Antarctic cold or Arctic cold? Let's first look at China's polar stations.
The Yellow River station in the North Pole is located at 79 degrees north latitude, and visitors there in the summer can find that the bays around the station have melted all the snow, a large number of tundra plants grow lush, and even a lot of flowering plants, Arctic ducks, Arctic terns and other seabirds active, showing a bird-scented scene, people doubt whether it really to the North Pole.
contrast, the Great Wall Station and Zhongshan Station in Antarctica are a different story, with year-round snow cover, low temperatures and few species of plants and animals.
data show that the average annual temperature in the Arctic is around -10C, with a minimum record of -70C, while the average annual temperature in Antarctica is -25C to -30C and the lowest record is -90C.
, the South Pole is colder than the North Pole.
so, what causes Antarctica to be colder than the North Pole? The first is the topographical difference between the South Pole and the Arctic.
The South Pole is a land area of about 14 million square kilometers, of which about 98 per cent is covered by ice sheets, which, on average, are nearly 2,000 metres thick and do not age.
The Arctic is surrounded by land, the Arctic Ocean is mainly surrounded by Eurasia, North America, an area of about 13.1 million square kilometers, of which the ice area of about 8.5 million square kilometers, only about 60% of the Antarctic ice area.
, the Arctic ice melts heavily in the summer, resulting in smaller areas of summer ice.
addition, the Arctic Ocean's sea water has a large thermal capacity, strong heat absorption skills, absorbing more heat, resulting in the North Pole is much warmer than the South Pole.
, the Antarctic is higher than the North Pole.
the average altitude of the Antarctic is 2,350 meters, of which more than 3,000 meters account for about 25 percent of the Antarctic continent, the highest of about 5,140 meters, is the world's highest average altitude of the continent.
nearly two-thirds of the Arctic is ocean, with an average elevation comparable to sea level.
the higher the altitude, the lower the temperature, which is called "higher than cold", so the Antarctic will be lower than the Arctic temperature.
, antarctic heat exchange is less than in the North Pole.
Because of the western wind currents and the southern ocean currents around the South Ocean, the Antarctic is relatively closed in both atmospheric and oceanic currents, with less heat exchange at low and medium latitudes and no effective heat supplement.
In contrast, the Arctic is more frequently exchanged with mid- and low-latitude atmospheric and oceanic currents, and heat from the mid- to low-latitudes can be efficiently transported through the ring to the Arctic, resulting in the Arctic being warmer than the South Pole.
reporter Fu Lili Source: Science and Technology Daily.