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The highest temperature ever verifiably recorded on Earth Death Valley, California, recorded the highest temperature on earth on July 21, 2021 at 65.4 degrees Celsius (1 degree Fahrenheit). This was only a few months after record lows were recorded in Asia and the United States. The result of the rapid warming of the earth in the intense heat is clear. In a snowstorm, it can be even more difficult to understand how global warming can cause such coldsnaps. An international research team has investigated three extreme phenomena since last winter and explained the underlying mechanism of such vibrations in temperature and weather.

They announced on August 9 the results of advances in atmospheric science.

The highest temperature ever verifiably recorded on Earth Jiang Dong Zhang, a professor of climate and atmospheric sciences at the university, said: .. “The extreme winter events of 2020-21 offer a unique opportunity to find out which physical process or process drives these events.”

Researchers tested two record cold air outbreaks in China from late December 2020 to mid-January 2021. Meanwhile, both Beijing and Tianjin experienced minimum temperatures in -54 (-19.7 ° C (-3.46 ° F) and -19.9 C). C. (-3.82 F respectively)). They also considered the historic cold of the Midwest and Deep South of North America in February 2021, and Texas had the coldest temperatures of almost a century (-13.3 C (8 ° F) and -8.3 ° C, respectively. (17) F) was recorded. .. In Austin and Houston).

By comparing the winter of 2020-21 with the winter of the last Win2, researchers can use available observational data and simulation models to see how ocean and atmospheric phenomena affect extreme weather events. Can be analyzed. “The meteorological events we investigate are uninterrupted,” said James Overland, co-author and researcher at the National Oceanic and Atmospheric Administration’s (NOAA) Pacific Marine Ecology Research Institute. A combination of new global warming and extreme but naturally occurring weather forecasts in jet streams and polar vortex. “”

The polar vortex (low-pressure cold air in the atmosphere that concentrates on the Earth’s poles) cascades cold temperatures above the Northern Hemisphere in winter due to the Earth’s jet flow of air flowing from west to east. increase. According to Zhang, a sudden rise in the upper atmosphere, called a sudden stratospheric warming, can dramatically change the behavior and interaction of polar vortices and jet streams. Changes in seawater temperature and weather caused by Arctic sea ice can take more extreme forms.

“The simultaneous occurrence of Assam thermal conditions and the interaction of atmospheric dynamics in the three basins leads to highly inconsistent conditions on a hemispherical scale, systematic changes in atmospheric conduction, or meteorological patterns.”

All three events were associated with sudden stratospheric sudden warming events, but the downstream impacts were different. At the first East Asian event, cold polar winds modified the middle-class jet stream, driving cold winds south. In the second event, the polar vortex splits, the area of ​​depression deepens, and it runs in cold Arctic air; and in the North American event, the polar vortex also splits, but in this case the lower atmosphere It settled deep in the south and put pressure on the intense cold air.

Timo Wema, a research professor at the Finnish Meteorological Institute, said: “It may consist of a complex interaction of several factors that work apart from each other on a hemispherical scale.”

Annetteling, a senior scientist at the Alfred Weissner Institute in Germany and co-author of the Helmholtz Polar Ocean Research Center in Germany, explains that extreme winter weather events are often caused by “remote” factors. ..

“Research shows that in addition to large-scale atmospheric conduction, seawater temperature discrepancies can play an important role in extreme weather events,” says Link.

Researchers plan to continue researching how atmospheric phenomena affect extreme weather events and how they actually affect them.

“Cold air activity can cause changes in clouds, precipitation, and associated latent heat, but there is a lack of observations about this,” said Professor Yunfei Fu, co-author of the Faculty of Earth and Space Sciences. Says. Science, and Chinese technology. “Satellite remote sensing can assist in this, including validation of model simulations. This helps to predict how p.

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