Why is the entire northern hemisphere so hot this summer?The three major reasons have caused the "high fever" of the weather to not retreat

This summer, "heat" is undoubtedly the most concerned keyword. Since June, high temperatures have been continued in many places across the country. Looking at the world, extreme weather and climate events represented by high temperatures in the northern hemisphere are also emerging.

In my country, in June, high temperatures were "first -time" in the north, and high -temperature red warnings were issued in many places. After entering July, the high temperature in the south "later lived up" and opened a long "barbecue" mode. As of now, the summer heat has not been exited, and there are even more and more intense trends. Although Beijing's high temperature this summer does not seem to be extremely extreme, as of now, it has been as many as 15 days at high temperature days (the highest temperature of the daily maximum temperature ≥35 ° C), which is obviously more than 9.7 days of the same period of the year. We invite Liu Zhao, Wang Liang, and Li Yue of the "China Meteorological Daily" professional authors to introduce the situation of high temperature weather this summer.

The strongest regional high temperature since 1961

How hot is this summer? Since June (June 1st to August 14th), the average number of high temperatures in the country is 11.8 days, which is 4.9 days than the same period of the year, the highest history since 1961.

Zhou Bing, chief expert of the National Climate Center Climate Services, introduced that my country ’s high -temperature weather since June 13 has the characteristics of long duration, wide range, strong strength, and strong extremes.

From June 13th to August 14th, the process of regional high temperature in my country has lasted 63 days, of which Zhushan (44.6 ° C), Chongqing Beiyi (44.5 ° C), Hebei Lingshou (44.2 ° C), Tancheng (44.1 ° C) , Zhengding (44.0 ° C) and Yunnan Yanjin (44.0 ° C) have a maximum temperature of 44 ° C or above, covering an area of ​​more than 5 million square kilometers, affecting the population of more than 900 million people.

This year's high -temperature incident is extremely rare in a sense. Compared with several high -temperature events since this century, the start time is significantly advanced and extremes are significantly enhanced. Combined with the high temperature process monitoring indicators of the National Climate Center, and then comprehensively comprehensively the intensity, scope and duration of high temperature events, the comprehensive intensity of high temperature events this year is the strongest since 1961.

Under the high temperature, the number of high temperature days in the 5 provinces of Suyu, Anhui, Zhejiang and Chuan, has the largest number of high temperatures since 1961. It is the second most in the same period since 1961, Hunan, Guizhou, Shaanxi, Shanghai, Shanghai, Shanghai, Shanghai, Shanghai, Shanghai, Shanghai, Shanghai, Shanghai, and Shanghai, and Gansu is the third. A total of 716 national meteorological observation stations in the country have reached the standard of extreme high temperature events. Hebei, Shaanxi, Sichuan, Zhejiang, Fujian, Guangdong and other places have the highest temperature or break through the historical extreme value. The temperature of Shanghai Xujiahui Station at 14:30 on July 13 reached 40.9 ° C, and the highest temperature record has been tied to the local meteorological record (1873).

Continuous high temperatures have adverse effects on production activities and people's health. Since June 13, Hebei, Shandong, Zhejiang, Henan, Shaanxi, Gansu, Ningxia, Xinjiang and other provinces (autonomous regions) power grids, as well as Northwest Power Grid and Southern Power Grid, have reached a record high. Last year, it increased by 33.56%; many people in Zhejiang, Jiangsu, Sichuan and other places confirmed fever. From July 1st to 14th, Shenzhen 120 received a total of 73 stroke first alarm; Due to the deviation of high temperature and less rain soil in northern Sichuan and other places, the meteorological drought in some areas sustained or developed.

As of now, the summer heat has not been exited, and there are even more and more intense trends.

The Central Meteorological Observatory continued to issue high -temperature red warning at 6 o'clock on August 16, which is already the Central Meteorological Observatory for 27 consecutive days of high temperature warning. The forecast shows that in the next 10 days, there will still be continuous high temperature weather in the Sichuan Basin, Jianghan, Jianghuai, Jiangnan and other places, and the cumulative high temperature can reach 7 to 10 days; 40 ° C.

Beijing this summer is not extreme but there are many days

"Beijing does not seem to be so hot this year." For Beijing citizens, this year's high temperature weather seems more ordinary.

The data proves that Beijing is indeed "not so hot" this summer, and there is no particularly extremely high temperature. Since the flood in this year (June 1st to August 15th), the average temperature in Beijing was 25.5 ° C, which was slightly higher than the same period (25.0 ° C) in the same year (25.0 ° C). However, it should be noted that the number of high temperatures in Beijing is as many as 15 days, which is obviously more than 9.7 days in the same period of the year.

The high temperature in Beijing this year is not late. On May 28, the Southern Suburb, which represents the "Beijing temperature", rose to 35.3 ° C during the day. The first high temperature day this summer was born, 13 days earlier than usual. The high temperature came early, but the subsequent development was not extreme. Shi Hongbo, deputy director of the Beijing Climate Center, introduced that the extreme high temperature since the flood this year was 39.2 ° C, which appeared on June 25. In history, the extreme maximum temperature in 13 years exceeded 39.2 ° C, and even reached 41.9 ° C in 1999. Compared with these years, the highest temperature this year is still common.

The reason why Beijing's high temperature is not extreme, and the trend of high pressure is still the main cause. "During the continuous high -temperature weather in Beijing in the early days of this year, the high -pressure ridge of the mainland was west, and it was in the junction of Xinjiang and Inner Mongolia. There was a slot over the northeast. The influence is relatively small, "Shi Hongbo said.

After entering August, Beijing ushered in the "sauna sky" for a period of time. The temperature was high and humid, and the public felt sultry and unbearable. Shi Hongbo introduced that the main flood season of Beijing's "seven or eight" (that is, late July to early August) is exactly the period when the water vapor is sufficient throughout the year. Recently, with the high pressure north of the Western Pacific subtly, the humidity of the Beijing area has increased, and the sinking of the air flow has caused a significant temperature increase, which has triggered a high temperature and high humidity. The actual temperature of this weather is generally not particularly high, but when it combines with humidity, it will aggravate the feeling of heat and make people sweat more than. Without precipitation, the weather will maintain such a state stable. This is also the normal state of Beijing's climate, which is normal. Shi Hongbo also reminded the public that the summer has not yet ended, and it is not possible to relax at high temperature. From the midsummer stage (July to August), as of August 15, 10 high temperature days have appeared in Beijing, and it has not ended in August, and high temperature days may still appear. "The average number of high temperature days from July to August of the previous year was 6.1 days. From historical data, 2000 is 15 days, 2010 is 14 days, 13 days in 1999, and 12 days in 1997. From the data in recent years, from the data in recent years, from the data from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data in recent years, from the data from the data in recent years, from the data in recent years. There are 11 days in 2017, and 10 days in 2018. "Shi Hongbo said that the possibility of temperature higher than 39.2 ° C in the later period is very small, but the number of high temperatures may increase.

Continuous high -temperature incident raging the entire northern hemisphere

Global is the same as this cool heat. High temperatures are not just raging in China, but formed a "warm atmosphere" in the entire northern hemisphere.

Britain, which has always been cool, issued the first abnormal high -temperature red warning since July 15. Four days later, on July 19, local time, the highest temperature in Britain exceeded 40 ° C for the first time. Many fires occurred on the same day, and the fire department announced the "major incident". Earlier, the highest temperature in the UK was 38.7 ° C, which was measured at Cambridge University Botanical Garden on July 25, 2019.

In southern Europe, high -temperature heat waves caused raging wildfires. The French and Spanish government dispatched more than a thousand firefighters on July 17 to work hard to control the spread of the fire. The Greek fire department also pointed out that 71 wild fires occurred in 24 hours. French President Macron said the area of ​​forest land that has been burned this year is three times that of 2020, "we are experiencing an unusually difficult summer."

Japan's high temperature impact is equally serious. According to the Japan Meteorological Agency, at 14:30 on August 11, local time, Isezaki, Kunma Prefecture, Japan observed 40.5 ° C at high temperature, which is the highest in Japan since this year. In addition, the Eight Prince City of Tokyo also observes a high temperature of 39.3 ° C. From August 1st to 10th alone, there were 5 elderly people 70 to 80 in Tokyo died of heat stroke.

Even the cold Arctic Circle cannot escape the high temperature impact. The US Cable Television News Network reporter Line Marush recently appeared in news about Greenland wearing short sleeves. She said in the video that Greenland's temperature is close to 60 Hua Shi (about 15.5 ° C), and warm weather like this is enough to wear short sleeves. Line Mash said that due to the rise in temperature, the ice cover of Greenland is melting at an alarming rate.

In June this year, the global average temperature was about 0.4 ° C higher than the year, the highest since 1979. Northern Hemisphere, Western Europe, South Europe, West Asia, Central Asia, East Asia, the United States, Africa and other places have continued high temperature incidents. Spain, Portugal, France, the United Kingdom and other places exceed 40 ° C temperature; by July, the temperature of the Arctic circle soared to 32.5 ℃.

The Secretary -General of the World Meteorological Organization (WMO) Petre Tallas pointed out on July 19 that in addition to seriously affecting human health, extreme high temperature weather will have further negative impact Severe crops reduced production.

The three major reasons have caused the "high fever" of the weather to not retreat

The heat waves are frequent, what is the reason for the "high fever"? Zhou Bing, chief expert of the National Climate Center Climate Services, believes that there are three levels of extreme high temperature in the northern hemisphere: the atmospheric circulation is abnormal to create the basic conditions of high temperature; It further enlarged the high temperature impact.

The so -called atmospheric circulation is abnormal, that is, the degree of departure of the circulation situation of atmosphere in different seasons and regional space operations and the perennial climate average. If the degree of deviation exceeds the threshold (such as 1 times or 2 times the standard deviation), it can be considered that the atmospheric circulation is abnormal. For example, the originally straight east -west circulation has transformed into a twists and turns north -south circulation.

This summer, the atmospheric circulation system in the northern hemisphere has appeared abnormal, showing the control state of consistent heating high -voltage circulation system. High pressure is an important source of high temperature. Under the influence of high -pressure systems, the heat is stranded on the ground, and it cannot be blown away or unable to disperse, resulting in the local temperature rise. In the northern hemisphere this summer, the Western Pacific subtropical high -pressure, Atlantic subtropical high -pressure, and Iran's high -voltage average enhancement have been enhanced, forming a large -scale overall global heating high -pressure zone.

At the same time, the "La Nina" climate incident that spanned 3 years played a role in helping the atmospheric circulation. The "La Nina" means that the sea water in the central and eastern Pacific becomes cold, which will cause the tropical weft ring circulation to strengthen, causing the gear effect of the secondary circulation of the weft ring. Since this spring, the "La Nina" incident has not been weakened, but has continued to strengthen. During this, the sea temperature in the Indian Ocean has also been abnormal. The two together promoted the continuous enhancement of the Western Pacific subtropical high pressure. What's more, it is the impact of global warming. In this high temperature in the northern hemisphere, it plays a role in heating and enlarged and modulation. In the context of global warming, the unstable global climate system has intensified, and extreme weather and climate events are frequent, wide, strong, and concurrency. The high -temperature heat waves that have been encountered in the past 50 years will become 10 years. strong.

Global warming affects from behind the scenes to front of the stage

Extremely high -temperature events are the most likely to connect with global warming, but it is far from the only impact of global warming. Today, global warming has moved from "behind the scenes" to the "front of the stage." It is fully aware that carbon emissions are the main cause of global warming. The recorded greenhouse gas concentration is pushing the temperature to rise, making the weather more extreme.

In addition to high -temperature heat waves, global warming will bring more heavy rainfall and floods. Data show that every time the global temperature rises by 1 ° C, the increase of atmospheric water vapor will increase by about 7%, which increases the probability of extreme precipitation. Rising temperatures can also lead to melting glaciers, drought in land, desertification, accelerate water evaporation and loss of soil and soil, and eventually form more extreme weather.

At present, the influence of global warming is increasingly presented in front of people: the Arctic Sea Ice is constantly decreasing, the Greenland Ice Covers are accelerating, and a large number of fires and insects in North America's northern needle leaf forests have begun to appear. Starting unblocking, the speed of the Atlantic Meridian to flipping the current slowly, Amazon's tropical rain forest precipitation reduction frequency drought, Australian warm water corals began to die on a large area, accelerate the melting speed of the southwestern pole ice cover, and accelerate the acceleration of the ice cover in the Southeast Polar Wilker. In the face of these phenomena, people cannot ignore the "red alarm of all mankind" issued by the Special Committee (IPCC) emphasized by the UN Secretary -General of Gutres (IPCC). The future of hot, more drought, and more waterlogging. "

Faced with a more severe climate challenge, people need to fully aware of the potential crisis and take practical action. Finding breakthroughs in reducing greenhouse gas emissions is the only way to deal with challenges.

Sichuan Observation (Source: Beijing Daily Client)

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