Why is the north hotter than the south? Will it be hotter in July and August?, 46 National Meteorological Stations Breaking Historical Extreme Values in North China | High Temperature | Historical

In recent days, high temperatures have developed rapidly in the North China and Huanghuai regions, with many places experiencing temperatures above 40 ℃. The Central Meteorological Observatory continued to issue an orange high-temperature warning on the 23rd.

What are the causes of sustained high temperature weather? When will it end? Why is the north hotter than the south?

Beijing breaks through 40 ℃

Affected by the warm air mass and strong solar radiation, as of 14:00 on the 23rd, the temperature at the Beijing Observatory had reached 40 ℃. Among the 556 meteorological monitoring stations in the city, 305 stations had a maximum temperature of 39 ℃ and above, and 158 stations had a maximum temperature of 40 ℃ and above.

"For the first time since the establishment of the observatory, it has exceeded 40 ℃ for 2 consecutive days." Zhang Yingxin, chief forecaster of the Beijing Meteorological Observatory, said that under the control of strong heating masses, the high temperature weather continued from the 23rd to the 25th. The Beijing Meteorological Observatory issued a high temperature red warning signal at 7 o'clock on the 23rd.

Zhang Yingxin said that this round of high temperature in Beijing has strong intensity and long duration. The main reasons are as follows: First, the Beijing-Tianjin-Hebei region has been controlled by the heating mass since the 21st. The heating mass is relatively strong and has a long impact time; Second, under the control of the high-pressure ridge situation, the sky is clear and cloudy, and there is no cloud cover, and the radiation warming is more favorable, which promotes the warming; third is just entering the summer solar term, long-term sunshine is conducive to the emergence and maintenance of high temperature; fourth, the air humidity is small and the weather is dry, which is also conducive to rising temperatures.

Will it get hotter in July and August?

Since June this year, the daily maximum temperature of 183 national weather stations has broken through the monthly extreme, 46 stations have broken through the historical extreme, and the daily maximum temperature in North China has broken through the historical extreme on June 22.

At present, it is only at the end of June. Will the temperature be higher in July and August?

In this regard, Gao Hui, chief forecaster of the National Climate Center, told reporters that there are obvious regional differences in the high temperature concentration period in various parts of China. The southern region usually enters the high temperature season in the midsummer period, while the northern region often enters the high temperature season in the early summer period.

For North China, high temperature weather is usually more likely to occur from June to early July before the rainy season, and high temperature for several consecutive days is also more common in June. This period of time is mainly dry heat type high temperature, high temperature and low humidity.

In late July, with the northward jump of the subtropical high and the northward advance of the summer monsoon, the water vapor transport and atmospheric humidity will increase, and the cloud cover will also increase, and there will be muggy weather, that is, humid heat type high temperature. As far as the maximum temperature is concerned, the maximum temperature value of the previous period is usually higher than that of the latter period. However, it should also be noted that the body's somatosensory temperature is not only related to air temperature, but also affected by humidity. Often this damp-heat type high temperature will increase the body's somatosensory temperature.

The frequency of extreme high temperatures will increase

Gao Hui said that under the background of global warming, the frequency of extreme high temperatures is increasing rapidly in both the south and the north. According to the forecast of the National Climate Center, the temperature in North China and Huanghuai this summer is on the high side, accompanied by an increase in the number of high temperature days, so it is more likely that the north will be hotter this summer than usual. In this case, there is also a certain possibility that some stations will break the historical extremes.

This year is the development of the El Niño event, is the high temperature in the north related to the El Niño event? Gao Hui said that it has entered the El Niño state, but the influence factors of the high temperature in the north in early summer are complex and cannot be simply attributed to the El Niño influence. "The existing scientific research results also show that the high temperature in the north in early summer is more likely to be affected by the sea temperature in the North Atlantic and the atmospheric circulation in the middle and high latitudes."

Zhang Fanghua, chief forecaster of the National Meteorological Center, said in an interview with reporters that recently, there have been two high-temperature weather processes in North China, Huanghuai and other places. The high-temperature intensity and long duration are mainly due to four reasons. First, North China, Huanghuai and other places are controlled by a relatively strong warm air mass, and its influence time is relatively long; the second is clear and cloudy under the control of the high pressure ridge, the warming of solar radiation is more favorable, and it also promotes the warming; the third is the summer solstice solar term, and the daytime is relatively long, that is, the sun shines for a long time during the day, and the long-term sunshine is conducive to the rise of temperature and the emergence and maintenance of high temperature; Fourth, in North China, Huanghuai and other places, the air humidity is small and the weather is dry, which is also conducive to the rise in temperature.

Zhang Fanghua said that after this round of high temperatures, it is expected that there will be high temperatures in North China, Huanghuai and other places from the 27th to the 30th.

Experts suggest that in the event of high temperatures, the public should try to avoid outdoor activities and work during the hottest hours of the afternoon. When staying outdoors for a long time, attention should be paid to replenishing water, sun protection, and body temperature changes to avoid heatstroke or heat stroke.