Meteorological experts refute rumors that "the coldest in 60 years"
The impact of each La Niña event is different. This winter is colder or warmer, scientific analysis and comprehensive judgment are needed
"This winter will be the coldest winter and the heaviest snowfall in 60 years" "The coldest year since 2008" "It's all related to La Niña"... Recently, a number of small videos and posts have been posted on Weibo, WeChat, Moments, etc. Forums etc. are widely circulated, and they are conclusive.
Yesterday, meteorological experts pointed out that these are just carefully edited rumors.
Due to the drastic cooling during the National Day holiday, these rumors are also extremely confusing, and many people believe it is true.
So, what is the reason for the drastic cooling during the National Day holiday?
Is La Niña in development behind the scenes?
Will the appearance and maintenance of La Niña make this winter extremely cold?
Yuan Yuan, a researcher at the Climate Prediction Office of the National Climate Center, answered these questions one by one.
Why did the temperature drop drastically during the National Day holiday?
During the National Day holiday, a strong cold air swept through the central and eastern regions, from central and western Inner Mongolia through the middle reaches of the Yangtze River all the way through southern China.
Affected by its influence, the lowest temperature in Northeast, North China and other places fell below the freezing point, and many scenic spots in Henan, Sichuan, Gansu, Inner Mongolia, Jilin, Heilongjiang and other places "unlocked" the winter scene mode early.
Is the snowfall in so many places too early?
Is it normal to cool down so violently?
Yuan Yuan pointed out that in early October, in northern my country, especially Inner Mongolia and Northeast China, the temperature dropped to freezing point and snowfall was normal.
From the climatological state (climate average over 30 years) data, the first frost began to appear in the middle and late September in northern my country, and the condition is that the minimum ground temperature drops to freezing point.
After entering October, although the temperature in most parts of the north and the central and eastern regions is lower than usual, this season should also be cold, breaking the freezing point, first frost, snow, etc., which are also scheduled to debut.
The sudden drop in temperature during the National Day holiday made people feel strong, which made the rumors spread.
The rumors in the short film are still plausible, saying that all this is caused by La Nina.
But in fact, this cooling process is a weather process, mainly affected by the large-scale atmospheric circulation anomaly, this weather phenomenon is not necessarily related to La Nina.
What does it mean to form a La Nina incident?
Yuan Yuan said that the La Niña state (event) refers to a phenomenon in which the sea surface temperature of the equatorial Central and Eastern Pacific is colder than normal, and the intensity and duration have reached certain conditions.
According to monitoring, since August, the equatorial Central and Eastern Pacific has entered the state of La Niña.
According to the prediction of the National Climate Center, the La Niña state will continue to be maintained in autumn, and it is expected to reach the peak in this winter, that is, a weak to moderate La Niña event will be formed this winter.
The appearance of La Niña is often associated with the overall "colder winter".
Since 2000, there have been 5 La Niña events. In terms of the status of the 5 La Niña events, the average temperature in parts of eastern Inner Mongolia, Northeast China, and North China in winter is 1℃~2℃ lower than normal in the same period, and some regions are 2℃ lower than normal. .
Will there be a cold winter this year?
Yuan Yuan emphasized that, generally speaking, in the winter of the peak of most La Niña events, the meridian of the atmospheric circulation in the middle and high latitudes of Europe and Asia may increase, and the cold air activities affecting my country are more frequent than normal. The low probability is greater.
However, it needs to be pointed out that the impact of each La Niña event is actually different, and not every La Niña year’s winter average temperature in my country is low.
Moreover, in the context of global warming, the factors affecting my country's winter climate are more complex. Factors such as melting of Arctic sea ice and changes in snow cover in Europe and Asia will affect the variability of the East Asian winter monsoon circulation, which in turn affects my country's winter climate anomalies.
Therefore, whether this winter will be colder or warmer, a comprehensive judgment based on scientific analysis is needed.
Text/Reporter Xie Li