The United Nations World Meteorological Organization (WMO) predicts that the La Nina phenomenon, which began in 2020, will last until the end of this year, and this will be the first "triple" La Nina phenomenon that has appeared in the 21st century.
La Nina is a phenomenon that the sea surface temperature in the eastern and central equatorial Pacific continues to cool abnormally in a large range. It usually occurs once every 2-7 years, and each lasts less than a year, which usually leads to disasters such as Atlantic hurricanes. "Triple" La Nina refers to the phenomenon lasting for three years and causing related disasters around the world. WMO said that with the increase in trade winds in in recent weeks, the La Nina phenomenon has been strengthened, and the ocean surface has cooled significantly, exacerbating drought and flood disasters in different parts of the world. It is reported that since 1950, the "triple" La Nina phenomenon, which lasted for three years, has only occurred twice, namely the mid-1970s and 1998-2001.
Maybe this winter is more difficult than summer? The scientific community has confirmed that the "Triple La Nina" may come
Just as early autumn entered, the weather in the north ushered in a large-scale cooling. Take some areas of Henan for example. Before they can clean up their summer clothes, they have to wear "winter clothes" in a blink of an eye. The temperature generally drops by more than 15 degrees, and the minimum temperature at night is only about 14 degrees. This is in sharp contrast to the "extreme high temperature" of more than 40 degrees half a month ago. Even experts from the Chinese Academy of Sciences also issued a warning that this year's meteorological changes are indeed very "rare".
Although we have survived a very unforgettable summer, the more terrifying "winter" may still be behind.
The scientific definition of the "La Nina phenomenon" refers to: "The seawater in the central and eastern Pacific region becomes abnormally cold."
Generally speaking, as long as meteorological data shows that La Nina phenomenon appears on the ocean, coastal areas or nearshore areas will usher in large-scale cooling. The scientific community will commonly call this weather "cold winter". However, the La Nina phenomenon is a normal link in the earth's meteorological changes. It is precisely because of the alternating climate of hot and cold that other natural forces such as monsoon and Hisense can play a role.
So it is not uncommon for La Nina to occur in winter, but the trouble is that the La Nina phenomenon this year seems to be a little different.
International meteorological community has been paying close attention to global climate change.
When signs of "subtropical high pressure" appeared in April, scientists predicted that this year's temperature changes may take the route of "big opening and closing". Sure enough, we ushered in a hot summer that can dry "Panyang Lake".
However, at that time, the scientific community had not discovered obvious temperature changes in the Pacific waters.
It was not until the end of May that staff at Yale University Meteorological Laboratory in the United States discovered the "water temperature abnormality" in the Pacific monsoon area. This is a high probability that La Nina will occur after autumn this year.
If that's all, it won't be too worrying. The problem is that we have just come out of the extreme high temperature climate, and the one that follows is the La Nina low temperature.
La Niña phenomenon itself is a correction to the " El Niño high temperature".
Such a large-scale and long-lasting high temperatures on land have caused the temperature in the Pacific waters to continue to drop, which has exceeded the temperature threshold in normal years.
According to mathematical logic, the scientific community speculates that this year's La Nina is about "three times" that of previous years. In short, it is what we call the "triple La Nina phenomenon".
If there are no other weather changes in the next three months, we have a 75% chance of ushering in a cold winter that we have not encountered in the past 15 years.
Although heat will certainly bring many problems, the earth's temperature changes essentially must maintain a balanced middle point, otherwise the damage caused by extreme cold is not less than that of high temperatures.
Fortunately, winter is the season when most animals and plants hibernate. In addition to having an impact on human social life, other species on the earth can still cope with the cold season, as long as it lasts not long.
What we need to worry about the most is how to deal with humanity’s own dilemma.
La Nina is the transliteration of Spanish "La Nina" and means "little girl". Meteorologists use it to refer to the phenomenon that the sea surface temperature in the eastern and central equatorial Pacific continues to cool abnormally across a large range, also known as anti-El Niño. Southeast trade wind blows the surface of the sun-heated sea water to the western Pacific Ocean, causing the west to increase nearly 60 cm higher than the eastern sea level, the sea water temperature in the west increases, the air pressure drops, and humid air accumulates to form typhoon and tropical storm , The seawater in the bottom layer of the eastern part turns upward, causing the seawater in the eastern Pacific to become cold. Since 1950, there have been 16 La Niña incidents around the world. According to the intensity level, it is divided into weak, moderate, and strong events. There has only been one Thunderbolt Nina incident in history, and it lasts from May 1988 to May of the following year.
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La Niña phenomenon often alternates with El Niño phenomenon , but the frequency of occurrence is lower than El Niño phenomenon. When the La Nina phenomenon occurs, my country is prone to cold winter and hot summer. There are more tropical cyclones landing in my country than in the past year, and there are more " drought in the south and flood in the north" phenomenon; there are more rainfall in Indonesia, eastern Australia, northeast of Brazil, and other places. ;Droughts are prone to occur in the equatorial region of Africa and southeastern United States.
La Nina phenomenon is the abnormal cold sea water in the eastern central and eastern Pacific Ocean. The southeast trade wind blows the surface of the sea water heated by the sun to the western Pacific Ocean, causing the west to increase by nearly 60 cm higher than the eastern sea level, the western sea water temperature increases, the air pressure drops, humid air accumulates to form typhoons and tropical storms, and the sea water in the bottom layer of the eastern sea is overturned. This causes the water in the eastern Pacific to cool.
La Niña and El Niño phenomenon On the contrary, with the disappearance of El Niño and the arrival of La Niña, weather and climate disasters in many parts of the world will also change. Overall, La Niña's temperament is not very mild, and its climate impact is roughly the opposite of El Niño. Its intensity and degree of influence are not as strong as El Niño, but its arrival may also cause disasters to many regions around the world.
The reason for the formation of
So how did La Nina form? El Niño is associated with the warming of sea temperature in the middle and eastern Pacific and the weakening of trade winds, while La Niña is associated with the cooler sea temperature in the middle and eastern Pacific and the enhanced trade winds. Therefore, in fact, La Niña is the product of the combined action of tropical oceans and the atmosphere.
The movement of the ocean surface is mainly restrained by the sea surface wind. The existence of trade winds causes a large amount of warm water to be blown to the western Pacific region of the equator. The warm water is scraped away in the eastern Pacific region of the equator, mainly replenished by cold water below the sea surface. The sea temperature in the eastern equator is significantly lower than that in the western Pacific. When the trade winds strengthen, the upturning phenomenon of deep seawater in the eastern equatorial Pacific becomes more severe, resulting in an abnormally low sea surface temperature, causing the airflow to sink in the eastern equatorial Pacific, and the upward movement of the airflow in the west is even more intensified, which is conducive to the strengthening of the trade wind , which further aggravates the development of cold water in the eastern equatorial Pacific and triggers the so-called La Niña phenomenon.
Trade wind refers to the wind blowing from the tropical region to the equatorial region in the low altitude. It is called the "Northeast Trade Wind" in the northern hemisphere and the "Southeast Trade Wind" in the southern hemisphere. Spanish , who lives in South America, uses This constant easterly wind sails to Southeast Asia for business activities. Therefore, trade wind is also known as trade wind.
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