In the past few days, Jiangxi has continued to issue high temperature warnings. In order to prevent high temperature heat damage and ensure the supply of fruits and vegetables, Gaoshi Township, Yongxin County organized volunteers to carry out agricultural picking activities.
Photo by Yan Jin/Guangming Pictures
At 18:00 on August 12, the Central Meteorological Observatory issued the first high temperature red warning this year. The highest temperature in parts of Shaanxi, Sichuan, Chongqing, Hubei, Hunan, Jiangxi, Anhui, Jiangsu, Shanghai, Zhejiang and other places can reach 40℃～42℃ , the local can exceed 42 ℃.
As of August 13, the Central Meteorological Observatory has issued a high temperature warning for 24 consecutive days.
This marks that the regional high temperature weather process that has continued to affect many parts of southern my country since June has reached the strongest stage so far.
According to Chen Lijuan, chief forecaster of the National Climate Center, this year's regional high temperature process will last for more than 62 days in 2013, making it the longest high temperature process since 1961.
How strong is the super high temperature?
Why is it so hot?
Will it become the norm in the future?
The reporter interviewed relevant experts from the China Meteorological Administration and asked them to interpret them one by one.
One question: How hot is the South this year?
This scorching summer, 40°C, which was unimaginable in the past, has become the "standard" in the southern region.
According to Wang Zhi, chief forecaster of the Shanghai Central Meteorological Observatory, as of August 13, Shanghai has experienced 6 days of high temperature above 40°C this year, with an extreme maximum temperature of 40.9°C.
In the next 10 days, Shanghai will continue to have hot weather, with the extreme maximum temperature reaching 40℃~41℃.
"Since July, the extreme temperature in most parts of Zhejiang has been between 39°C and 43°C, with the highest being 43.1°C in Sanmen, 42.9°C in Yongjia, and 42.4°C in Qingtian and Yunhe. Sanmen and Yongjia have both broken record highs. "According to Lou Xiaofen, chief forecaster of the Zhejiang Meteorological Observatory, it is expected that in the next 7 days, some areas in northern Zhejiang and western Zhejiang will experience extremely hot weather of 43°C, or break the record of extreme high temperature.
The high temperature in Chongqing will also continue to exert its strength in the characteristics of large-scale and high-intensity in July.
According to Luo Juan, chief forecaster of the Chongqing Meteorological Observatory, it is expected that from August 13 to 22, the highest temperature in most parts of Chongqing will be 38℃~42℃, and the local temperature will reach 43℃~44℃. The highest temperature in some districts and counties will be close to or exceeds historical extremes.
"At present, the regional high temperature process has not exceeded 2013." Chen Lijuan introduced that the high temperature weather in the south will continue in the next two weeks. "In terms of duration, this year's regional high temperature process will exceed the 62 days in 2013 and become the year of 1961. The longest high temperature process ever."
Second question: Is it normal for this summer to be so hot?
"From late July this year to the present, there have been large-scale and high-intensity high-temperature weather in the middle and lower reaches of the Yangtze River. The cause is related to the abnormal conditions of atmospheric circulation." Chen Tao, chief forecaster of the Central Meteorological Observatory, explained that from the current monitoring point of view , the subtropical high in the western Pacific is large in scope and strong in intensity. The southern part of my country is controlled by the downdraft of the subtropical high, the sky is clear and less cloudy, and the near-surface heating is strong due to the influence of sunlight radiation during the day, so large-scale high temperature weather occurs.
"The strong anomaly of the subtropical high pressure in the western Pacific this year is closely related to this year's global SST anomaly." Chen Lijuan added.
Chen Tao introduced that for a period of time in the future, the cold air in the middle and high latitudes will be weak, and there will be no obvious tropical system on the southern tropical ocean to affect my country. Therefore, the subtropical high pressure will continue to control the Sichuan Basin to the middle and lower reaches of the Yangtze River, and the high temperature weather will continue to develop.
"Affected by the high temperature weather, some areas from the Sichuan Basin to the middle and lower reaches of the Yangtze River in China have already experienced meteorological drought. In the future, this meteorological drought may continue or worsen."
On August 12, the Central Meteorological Observatory issued the first high temperature red warning this year. How long will the warning last?
According to Chen Tao, it is expected that in the next two weeks or so, the high temperature weather process will continue from the Sichuan Basin to the middle and lower reaches of the Yangtze River.
"However, the range and intensity of high temperature weather may change to some extent, so the warning level will be adjusted and updated according to the actual weather and forecast conditions."
In response to doubts about whether the forecasts appearing on the Internet have deliberately lowered the temperature, Chen Tao responded: "The temperature forecasts and live analysis are mainly based on scientific atmospheric observation data, and real-time dynamic analysis and adjustment, and will not deliberately lower the high temperature."
Three Questions: The heat continues, what impact will it have on production and life?
High temperature weather has a certain adverse impact on agricultural production in the southern region, and continuous high temperature is not conducive to the growth and development of some crops, especially some economic forest and fruit crops.
For example, tea trees or citrus, mango and other fruits in the Jiangnan region are vulnerable to high temperature and heat damage.
"In response to high temperature weather, measures should be taken as soon as possible to carry out water replenishment operations and sprinkler irrigation to cool down, and to remove the fruits that have been affected by heat damage as soon as possible." Chen Tao said.
Will there be summer and autumn droughts?
Chen Lijuan said: "According to our analysis, the possibility of less precipitation in the Yangtze River Basin in the later autumn is still relatively large, especially in the middle and lower reaches of the country, there may be continuous droughts in summer and autumn."
In cities, the surge in electricity demand is one of the most noticeable effects of persistent heat.
Chen Tao reminded: "The frequency of use of air conditioners and other electrical appliances has increased significantly under high temperature, which has a greater impact on energy supply. Relevant departments should make emergency plans based on temperature forecasts to ensure power supply."
For the public, Chen Tao suggested that long-term outdoor activities should be minimized during high temperature weather, and water should be replenished in time to avoid heat stroke and other potential diseases that are easily induced by high temperature.
"It is especially important to note that during the summer vacation, in the hot weather, students who are at home on vacation must pay attention to stay away from dangerous waters to prevent drowning accidents." Chen Tao reminded.
Four questions: Will it be so hot next summer?
"The occurrence of high temperature and heat wave events in summer is normal from a climatic point of view, but the duration, intensity, and impact range of high temperature and heat wave events this summer have indeed reached a very strong level."
Chen Lijuan's analysis: "The rare high-temperature weather that has occurred in my country since June this year may be the strongest high-temperature event since complete meteorological records began in 1961. The occurrence of such a situation is far from a problem of the weather scale. climate-scale reasons.”
"In the context of global warming, high temperature and heat wave events may become a new normal."
Chen Lijuan introduced that according to the IPCC Sixth Assessment Report, in the context of global warming, many changes in extreme weather and climate events have been observed since the middle of the 20th century, among which the frequent occurrence of high temperature and heat waves is a very significant feature.
"In the context of global warming, similar to this year's high temperature and heat, the frequency of occurrence may be more in future summers." Chen Lijuan said, "This year's high temperature appeared earlier and is expected to end later. The characteristics of 'starting early and ending late' will become more and more obvious in the future."
(Reporter Cui Xingyi of this newspaper, Beijing, August 13)