What is the El Nino phenomenon? What impact will it bring to our lives?

Hot! The frequent occurrence of El Nino phenomenon has aroused widespread concern. We always associate it with extreme weather. Then what is El Nino? How is El Nino formed? What is the impact of El Nino on the global climate? What is the expected intensity and impact of this round of El Nino? With these questions, let's look down.

1. What is El Nino?

"El Nino" is a transliteration of Spanish. It is not a weather phenomenon, but a climate phenomenon, which generally lasts for 9- 12 months. "El Nino" event will have an impact on the global climate, and its development has a periodicity of 2-7 years. Generally speaking, if the sea surface temperature in the equator, the Middle East and the Pacific Ocean remains abnormally warm for at least 5 months, it can be judged that an El Ni? o event has occurred.

Second, the El Nino phenomenon.

The United Nations World Meteorological Organization (WMO) issued a statement on July 4, saying that El Ni? o occurred for the first time in the tropical Pacific in seven years.

Imagine how the subtle changes in the sea will change our world! El Nino phenomenon swept the whole earth by changing the heat exchange between the global ocean and atmospheric system. This has led to many surprising phenomena and influences.

First of all, El Nino makes the originally wet area dry, and the originally dry area becomes wet. For example, El Nino can lead to droughts in the western United States and Australia, and floods in Peru and other places.

Secondly, El Nino has also had a great impact on global fisheries and agriculture. Due to the change of marine environment, the habitats of fish and plankton have also changed, resulting in changes in fishery resources. Crops will also be affected by drought or flood caused by El Nino, and the output fluctuates greatly.

The weakening of the southeast wind will reduce or stop the flooding of cold water in the Pacific Ocean, leading to abnormal warming of sea water temperature in a wide range. The traditional equatorial airflow and atmospheric circulation anomalies lead to abnormal precipitation in some areas along the Pacific coast and severe drought in others.

There are other reasons, such as slow rotation of the earth, volcanic activity and global warming.

Finally, El Nino has an indirect impact on global climate change. It will change the intensity and direction of global average temperature, precipitation and wind direction. These changes have a far-reaching impact on the balance between environment and ecosystem.

3. What impact will El Nino bring to us?

1, temperature

According to the analysis of historical data by the National Climate Center, in the summer of El Ni? o development year, the temperature in southern North China, northern Central China, central East China and eastern Northwest China is relatively high, and the number of high temperature days in some areas can reach more than 30 days.

In view of the possible staged high-temperature heat wave, high-temperature weather may lead to heatstroke and heatstroke, and the risk of cardiovascular and cerebrovascular diseases will also increase. It is recommended that the public go out to do a good job of sun protection, and outdoor workers should try to avoid direct sunlight. It is necessary to seize the favorable weather opportunity to carry out artificial precipitation enhancement in time, strengthen the water storage and conservation work of Tangba Reservoir, and actively draw water and lift water to fight drought.

Step 2 precipitate

In the summer of El Nino development year, the subtropical high in the western Pacific was strong to the south, which led to more precipitation in South China. Recently, frequent heavy precipitation in south China and south China is one of the manifestations affected by El Nino.

After the occurrence of El Nino, the precipitation distribution pattern of "less in the north and more in the south" is easy to appear in eastern China in autumn and winter, and the waterlogging phenomenon in southern cities is prominent, and the probability of "warm winter" increases; There is little precipitation in the north and it is prone to drought. For example, there were continuous droughts in summer and autumn in parts of North China and Huanghuai in 2002, a large-scale autumn drought in central and eastern China in 2006, and a staged drought in Huanghuai and Jianghuai in autumn of 20 18.

According to the forecast of the National Climate Center, under the background of strengthening the development of El Ni? o, it is predicted that in the summer of 2023, there will be more precipitation in southern East China, southern Central China and southwestern China, and the risk of flooding will be high. The precipitation in the eastern part of northwest China is easy to be less, and the possibility of meteorological drought is great.

At present, there are many factors affecting climate anomalies, especially high temperature, drought and flood. And extreme events are complex, and El Ni? o is just one of them. We can make preparations in advance, pay attention to the latest weather information, and learn to save ourselves scientifically, so as to minimize the loss when disastrous weather really comes.