Source: Jimu News
Jimu news reporter Chen Xi
Thousands of miles away, the temperature of the sea on the surface of the central and eastern Pacific Oceans of the equator remotely directs the changes in the wind and clouds above us. I was experiencing a warm autumn, but there was news of La Niña's "cold".
According to the National Climate Center, since July this year, the sea temperature in the central and eastern Pacific oceans of the equator has continued to decline, and this winter will form a weak to moderate la Niña event.
Today (4th), the center also released this winter's national climate trend forecast, the overall temperature in the central and eastern regions is mainly cold.
In the past La Niña incident, was the temperature in Hubei cold? Is cold winter? The Jimu news reporter asked meteorological experts to interpret this in detail.
Must the annual temperature in La Niña be on the low side?
There are 4 years when the temperature is high in Hubei
La Niña means "la ni a" in Spanish – "little girl, holy girl". The La Niña event refers to the phenomenon of cold water with a wide range of cold water in the surface temperature of the central and eastern Pacific Oceans in the equator, and the intensity and duration reach certain conditions.
It is the product of a combination of tropical oceans and atmospheres. It is associated with El Niño (where the sea surface water temperature continues to be higher than normal) and is thought to be an important cause of the global anomaly.
According to the news released by the National Climate Center, since 1950, there have been 16 La Niña events in the world, and from the historical data, the temperature in the central and eastern regions of China in the winter of the La Niña year is often low.
The La Niña incident since 1950
"It's not that I met 'La Niña', the temperature in Hubei is low in winter."
Xiao Ying, senior engineer of the Wuhan Regional Climate Center of the Hubei Meteorological Bureau, said that in the 16 La Niña events, the winter temperature in Hubei in the four years of 1964, 1998, 2000 and 2020 was on the high side.
In particular, the winter of 2020 is still a strong and warm winter (December 2020 to February 2021), of which the average temperature in Hubei in February this year is the highest since 1961, and the temperature in Wuhan on February 22 jumped to 28.2 °C, and everyone should have an impression of the unusual warmth of February.
The temperature is low and cannot be directly equated with cold winter.
Xiao Ying said in detail that the definition of cold winter is that the average temperature of a single station in winter is a cold winter station with a low temperature of more than 0.5 °C (a low range of 0.5 °C to 1 °C, which is a weak cold winter, and a low amplitude exceeds 1 °C, which is a strong cold winter), and the number of cold winter stations in the province accounts for more than half, Hubei is a cold winter; if the low amplitude does not exceed 0.5 °C, it is a normal winter.
Therefore, in the 16 La Niña events, Hubei had 12 years with low temperatures, but 5 years were normal winters (1970, 1988, 1995, 2010 and 2017), and only 7 years were cold winters (1950, 1954, 1973, 1975, 1984, 2007 and 2011), such as January 12 to February 3, 2008, Hubei appeared since 1954/ The worst sustained low temperature rain, snow and freezing weather and climatic event since the winter of 1955, the winter of 2007/2008 was a strong cold winter.
Why is La Niña still bubbling under global warming
It is a small wave on a warming wave
Some people wonder: in the context of global warming, how did the cold temperament of La Niña emerge?
"Global warming does not mean that La Niña is gone, and there have been six La Niña events since the 21st century."
Xiao Ying explained that global warming is a large-scale climate trend from the intergenerational (more than 10 years) or longer time length, while La Niña is only an interannual scale in the climate system, generally appearing once in 2-7 years, "If global warming is compared to a big wave, it is a small wave on this wave, which cannot stop the trend of warming." ”
The National Climate Center also pointed out that it should be noted that east Asian winter winds are still the key factors in controlling China's climate in winter. What does this mean?
"Climate is the result of multiple system roles working together, and La Niña is a little bit more dramatic, but you can't ignore other characters." Xiao Ying said that the wind on the ocean or the wind overhead has a greater impact on us? Definitely the wind overhead. Therefore, we must also pay attention to the East Asian winter wind on our doorstep.
This winter, the temperature has changed significantly
The probability of stage extreme strong cooling is large
The National Climate Center released a national climate trend forecast for this winter today (4th): the cold air activities affecting China this winter are frequent and the forces are strong, the temperature in the central and eastern regions is generally cold, and the precipitation is generally distributed in the north and south.
It is worth noting that the phased changes in temperature this winter are obvious.
In December this year, most of the national temperature is close to the same period of the year (1991-2020 average) or high; but the cold air activity will be significantly stronger in January and February next year, and the temperature in most parts of central and eastern China may be lower than the same period of the year, and the possibility of a stage of extreme strong cooling events is greater.
What kind of painting style will Hubei have this winter? "Cold air is active, the probability of low temperature is large, the probability of less precipitation is large, and there are stages of rain and snow." Xiao Ying gave the current prediction and judgment.
Because the factors affecting China's climate are very complex, coupled with the recent increase in climate volatility, it is difficult to predict, the meteorological department will closely monitor the weather and climate change, strengthen analysis and research, and also ask you to pay attention to weather forecasts in time.
The strongest cold tide shows muscles during the winter season
Ice and snow or locked in the alpine regions of western Hubei
Don't look at today (4th) Wuhan is still 20 ° C, the 7th is the winter, the cold tide is also tight, and it is the strongest cold wave this year, how strong is it?
The Central Meteorological Observatory continued to issue a yellow warning of cold wave at 18:00 today: Affected by the cold wave, from 20:00 on the 4th to 8:00 on the 8th, China will have a windy cooling weather process from northwest to southeast:
The temperature in most areas will drop by 8 °C to 10 °C successively, and the temperature in the northwest, most of Inner Mongolia, north China, Huanghuai, western Jianghuai, and southern Northeast China will drop by up to 12 °C-14 °C, and the local area will be above 16 °C; accompanied by 4-6 northerly winds and gusts of 7-8 degrees; the minimum temperature line of 0 °C on the morning of the 8th is located in central Shandong, central Henan to northern Sichuan, and the minimum temperature in northern South China will drop to about 10 °C.
It seems that Guangdong is also associated with the word "cold".
Forecast map of wind cooling
When the cold wave passes through Hubei, what drastic changes will occur in the weather?
The Wuhan Central Meteorological Observatory predicts that the strongest cold wave this year will affect our province from north to south on the 6th to 8th, accompanied by small to moderate rain and local rain and snow freezing.
This process has the following characteristics:
First, the cooling range is large, the province will appear a large-scale cooling from the night of the 6th, the decline is generally 8 ° C to 10 ° C, the local can reach more than 12 ° C; the second is that the temperature is low, the lowest temperature appears in the morning of the 8th, the northern region is generally -1 ° C to 2 ° C, the southern region is 3 ° C to 5 ° C, but the temperature rises faster, the lowest temperature on the morning of the 9th is 5 ° C to start; the third is the wind, the evening of the 6th to the day of the 7th, most of the northerly wind is 4-6, the gust is 8-10; the fourth is that the western alpine area has rain and snow freezing, especially the night of the 6th, There will be sleet or light to moderate snow, partial heavy snow, and frozen weather in the alpine regions of northwest Hubei.
Today, the Wuhan Meteorological Bureau released a special report on major meteorological information:
From the evening of the 6th to the 8th, affected by the strong cold air in the north, a cold wave process occurred in Wuhan, accompanied by strong winds, cooling, precipitation weather, the process cooling range can reach 9 ° C -11 ° C; of which there is light to moderate rain during the day from the night of the 6th to the 7th, the northerly wind is 4-6, the gust is 7-9, the maximum temperature drops to 10 °C-12 °C; the night of the 7th turns sunny, due to radiation cooling (no cloud insulation), the temperature continues to drop, and the lowest temperature appears on the morning of the 8th, which is 2 °C-4 °C; after the temperature rises, Since the 9th, the maximum temperature has risen to 15 °C.
According to the meteorological department, the temperature in Hubei Province in the early stage was obviously high, the cold wave weather cooled violently during the process, the wind was strong, and there was rain and snow freezing in the western mountains, so it was recommended:
Strengthen the prevention of the adverse effects of high winds on buildings, agricultural facilities, transportation and shipping, and outdoor operations; strengthen health protection, do a good job in cardiovascular and cerebrovascular and respiratory disease prevention; the western mountainous areas need to do a good job of rain, snow and freezing prevention, in case of rain and snow weather, everyone adjusts the travel plan as much as possible; the weather changes suddenly, the temperature falls off a cliff, the minimum temperature in Hubei does not exceed -1 ° C, the rain and snow add cold, the body feels colder, everyone's down jackets and cotton clothes and other winter clothes should be prepared, strengthen cold protection and warmth.