Traditional Culture Encyclopedia - Weather inquiry - Is the coldest winter 2020 true? How cold is La Nina's winter?

Is the coldest winter 2020 true? How cold is La Nina's winter?

Recently, the northern and southern cities of China have entered the winter rapidly, and many cities in the north have ushered in heavy snow, while many cities in the south have also entered the winter overnight, and it has become particularly cold in an instant. And many citizens are also lamenting that this winter will be the coldest winter in 60 years, so is this true?

In 2020, "La Nina" has lasted for 10 month, and the Leng Hai surface temperature in the equatorial, middle east and Pacific Ocean has been continuously developed and strengthened. It is expected that La Nina will continue in the later period and reach its peak in winter, forming a weak to moderate intensity La Nina event. This incident may last until next spring.

Since June 65438+ 10, La Nina has developed rapidly, especially in the last three periods from June 65438+ 10 to June 65438+ 10/,and the Nino3.4 index is lower than-1. Judging from the spatial pattern of SST development, the SST anomaly in most parts of the equatorial Middle East and Pacific Ocean is below -0.5℃ at present, and the negative anomaly center is located in the area from west longitude 120 to west longitude 150.

In the winter of most La Nina years, the meridional degree of atmospheric circulation in middle and high latitudes in Europe and Asia may increase, and the cold air activities affecting China (including East Asia) are more than normal, and the probability of lower temperature in central and eastern China is higher than normal.

However, it should be noted that under the background of global warming, the factors affecting the winter climate in China (including East Asia) are more complicated, and La Nina is only one of the important factors, and the influence of La Nina is different every time. In addition to La Nina events, factors such as the melting of Arctic sea ice, the change of snow cover in Europe and Asia and the plateau will also affect the variability of East Asian winter monsoon circulation.

"La Nina" Impact From the perspective of global impact, when most La Nina events occurred, the precipitation near the coast of South America decreased, while that in Indonesia and eastern Australia increased; Drought often occurs in central Africa and the southeastern United States, while floods are prone to occur in northeastern Brazil, India and southern Africa.

The latest seasonal forecast also confirms this point: there is less rainfall in the Horn of Africa, less rainfall in Central Asia and more rainfall in Southeast Asia, some Pacific islands and northern South America.

Since 1950, there have been 15 La Nina events in the world. Among them, only 1 strong La Nina event lasted from May 1988 to May of the following year. There are 8 moderate intensity events; Everything else is weak.

Comprehensive analysis shows that the current development characteristics of La Nina state this year are similar to those of La Nina events in 1995 and 2007.

In response to the current situation, "La Nina" has announced that La Nina continues, and initiated relevant actions and plans of climate-sensitive departments such as agriculture, health, water resources and disaster management. The World Meteorological Organization (WMO) is also increasing its support and advice to international humanitarian agencies, so as to improve its ability to respond to the COVID-19 epidemic and try its best to reduce the impact on the most vulnerable people.

"La Nina usually has a cooling effect on global temperature, but this effect may also be offset by the heat captured by greenhouse gases in our atmosphere." World Meteorological Organization Secretary-General Petiri Talas said.

According to the ENSO update report of the World Meteorological Organization, by the end of 2020 or even the first quarter of 20021year, the sea surface temperature in the tropical Pacific is likely to remain at La Nina level.

It is worth noting that El Nino and La Nina are not the only factors driving global and regional climate patterns. No two La Ni? a events or El Ni? o events are the same, and their impacts on regional climate may be different at different times of the year and other factors. Therefore, decision makers need to pay close attention to the latest seasonal forecast in time to get the latest information.

WMO is strengthening the integration of information provided through national and regional climate outlook forums, and increasing the frequency of global seasonal climate update (GSCU) from quarterly to monthly. In addition to El Ni? o and La Ni? a, GSCU also considered the impacts of other climate drivers to evaluate their possible impacts on regional surface temperature and precipitation patterns.

In addition, after the devastating impact of the 20 15/20 16 El Ni? o event, the Food and Agriculture Organization of the United Nations, the World Meteorological Organization and humanitarian organizations jointly established the ENSO Group to ensure that the United Nations and its humanitarian partners received appropriate recommendations for action. The group is currently providing impact-based recommendations to the United Nations and humanitarian agencies. Seasonal climate information from the World Meteorological Organization and other professional centers has been incorporated into a broader humanitarian assessment to identify those areas that are considered to be at the highest risk, and to make a more comprehensive assessment of actual vulnerability by combining food security, coping capacity and many other factors.

At present, relevant work has been carried out to transfer professional meteorological knowledge directly to decision makers by establishing a special coordination mechanism, so as to expand support for the humanitarian system and ensure the safety of life and property. This will provide information that spans time and scope for disaster management. For example, during the recent floods in Sudan, the World Meteorological Organization provided hydrometeorological information to the Office of the United Nations High Commissioner for Refugees.

Is 2020 the coldest winter? It snowed for the first time this autumn in the solar terms of the autumnal equinox, and the specific time was around 65438+1October 3. It snowed in North China, Northwest China, Northeast China and even the mountainous areas of Henan in the Central Plains. It is because of the large-scale heavy snow, coupled with the early time and cold weather during the autumnal equinox solar terms, that some people suggested that this winter might be the coldest winter in 60 years. But then experts came out to refute the rumor.

In the meantime, the coldest winter is still inconclusive. Finally, the World Meteorological Organization came out to clarify that there will be a strong La Nina phenomenon this winter, but it is understandable that the world is so big and the climate conditions on all continents are different. It is difficult to keep the temperature constant by "maximum", but what is certain is that it will be very cold and snowy this winter.

Meteorologists stressed that, generally speaking, in the winter when most La Ni? a events are in full swing, the latitude of the atmospheric circulation in the middle and high latitudes in Europe and Asia may increase, and the cold air activities affecting China are more frequent than normal, and the temperature in the central and eastern regions of China is lower than normal.

But what needs to be pointed out in particular is that the impact of each La Nina incident is actually different. Not every winter in La Nina, the average temperature in China is low. Moreover, under the climate background of global warming, the factors affecting China's winter climate are more complicated, such as the melting of Arctic sea ice and the change of snow in Europe and Asia, which will all affect the variability of East Asian winter monsoon circulation, and then affect the winter climate anomaly in China.

Therefore, whether it is cold or warm this winter needs to be comprehensively judged on the basis of scientific analysis.

Tips 1。 Keep warm, cold and antifreeze.

2. Keep warm when traveling and pay attention to falling.

3. Drive slowly in snowy days.

4. Pay attention to ventilation in case of fire to prevent gas poisoning.

5. Pay attention to heat to keep out the cold.

6. Soak your feet with hot water before going to bed to promote blood circulation