At 18:00 on August 12, the Central Meteorological Observatory issued the first red warning of high temperatures this year, and the maximum temperature in parts of Shaanxi, Sichuan, Chongqing, Hubei, Hunan, Jiangxi, Anhui, Jiangsu, Shanghai, Zhejiang and other places can reach 40 °C ~ 42 °C, and the local area can exceed 42 °C.
As of August 13, the Central Meteorological Observatory has issued a high temperature warning for 24 consecutive days. This marks the strongest stage to date of a regional high temperature weather process that has continued to affect many parts of the southern part of the continent since June. According to Chen Lijuan, chief forecaster of the National Climate Center, this year's regional high temperature process will last longer than 62 days in 2013, becoming the longest high temperature process since 1961.
How strong is the super high temperature? Why is it so hot? Will the future become the norm? The reporter interviewed the relevant experts of the China Meteorological Administration and asked them to interpret them one by one.
In recent 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, Yongxin County Gaoshi Township organized volunteers to carry out activities to help farmers pick. Photo by Yan Jin/Guangming Pictures
A question: How hot is it in the South this year?
This scorching heat, the 40°C that was previously unimaginable, 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 a total of 6 days of high temperatures above 40 °C this year, and the extreme maximum temperature is 40.9 °C. In the next 10 days, Shanghai will continue to have high temperature weather, with extreme maximum temperatures reaching 40 °C to 41 °C.
"Since July, the extreme temperature in zhejiang has been 39 °C to 43 °C, the highest is Sanmen 43.1 °C, Yongjia 42.9 °C, Qingtian, Yunhe is 42.4 °C. Places such as Sanmen and Yongjia have broken record highs in history. According to Lou Xiaofen, chief forecaster of the Zhejiang Meteorological Observatory, it is expected that in the next 7 days, there will be local 43 ° C extreme heat in northern Zhejiang and parts of western Zhejiang, or break the extreme high temperature record.
Chongqing's high temperatures will also continue to be strong in July's large-scale and high-intensity characteristics. According to Luo Juan, chief forecaster of the Chongqing Meteorological Observatory, it is expected that from August 13 to 22, the maximum temperature in most parts of Chongqing will be 38 °C to 42 °C, and the local area will reach 43 °C to 44 °C, and the maximum temperature in some districts and counties will be close to or exceed the historical extreme.
"At present, the regional high temperature process has not exceeded that of 2013." Chen Lijuan said that in the next two weeks, the high temperature weather in the south will continue, "in terms of duration, this year's regional high temperature process will exceed 62 days in 2013, becoming the longest high temperature process since 1961." ”
Second question: Is it normal that it's so hot this summer?
"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, and the reasons for this are 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 pressure range of the western Pacific Ocean is large and the intensity is strong, the southern part of the mainland is controlled by the sub-high sinking air flow, the sky is clear and cloudless, and it is strongly heated near the ground by the daytime insolation radiation, so there is a large range of high temperature weather.
"The strength of this year's subtropical high pressure anomaly in the western Pacific Ocean is closely related to this year's global SST anomaly." Chen Lijuan added.
Chen Tao introduced that in the future, the cold air in the middle and high latitudes will be weak, and there is no obvious tropical system affecting the mainland in the southern tropical ocean, so 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 high temperature weather, parts of the sichuan basin of the mainland to the middle and lower reaches of the Yangtze River have already experienced meteorological drought, and this meteorological drought may be further sustained or aggravated in the future."
On August 12, the Central Meteorological Observatory issued the first red warning of high temperatures this year, how long will the warning time last?
Chen Tao said that it is expected that in the next two weeks or so, the Sichuan Basin to the middle and lower reaches of the Yangtze River will continue the high temperature weather process. "However, the scope and intensity of high temperature weather may change to a certain extent, so the warning level will be adjusted and updated on a rolling basis according to the actual weather and forecast conditions."
In response to the question of whether the forecast appearing on the Internet deliberately lowered the temperature, Chen Tao responded: "Temperature forecasting and live analysis are mainly based on scientific atmospheric observation data, and real-time dynamic analysis and adjustment, and will not deliberately adjust the high temperature to low." ”
Three questions: What is the impact of the continuous heat on production and life?
High temperature weather has a certain adverse impact on agricultural production in the southern region, and the continuous high temperature is not conducive to the growth and development of some crops, especially some economic forest fruit crops. For example, tea trees in the Gangnam region or fruits such as citrus and mango are vulnerable to high temperature and heat damage. "In view of the high temperature weather, it is necessary to take measures as soon as possible to carry out water replenishment operations and sprinkler irrigation to cool down, and remove the fruits that have been affected by heat damage as soon as possible." Chen Tao said.
Will there be a summer and autumn drought?
Chen Lijuan said: "According to our analysis, the possibility of less precipitation in the Yangtze River Basin in the late autumn is still relatively large, especially in the middle and lower reaches of the yangtze River Basin, there may be summer and autumn drought. ”
In cities, the surge in electricity demand is one of the most significant effects of the continued high temperatures. Chen Tao reminded: "The frequency of use of electrical appliances such as air conditioners under high temperatures has increased significantly, which has a greater impact on energy supply, and relevant departments should make emergency plans according to temperature forecasts to ensure power supply." ”
For the public, Chen Tao suggested that during high temperature weather, it is necessary to minimize long-term outdoor activities, replenish water in time, and avoid the impact of heat stroke and other potential diseases that are easily induced by high temperatures.
"It is particularly important to note that it is the summer, in the hot weather, when students who are on vacation at home swim in the water to escape the heat, they must pay attention to staying away from dangerous waters to prevent drowning accidents." Chen Tao reminded.
Four questions: Will it be so hot next summer?
"High temperature heat wave events in the summer are normal from a climatic point of view, but the duration, intensity, and scope of this summer's high temperature heat wave events have indeed reached a very strong level."
Chen Lijuan analyzed: "The rare high temperature weather on the mainland since June this year may be the strongest high temperature event since 1961 when there was a complete meteorological record. The occurrence of such a situation is far from a problem of weather scale, and there are deep climatic scale reasons behind this. ”
"In the context of global warming, high-temperature heatwave events could become a new normal."
Chen Lijuan introduced that according to the sixth assessment report of the IPCC, in the context of global warming, many changes in extreme weather and climate events have been observed since the middle of the 20th century, of which the frequent occurrence of high temperature heat waves is a very significant feature.
"In the context of global warming, similar to this year's high temperatures and heat, in the future summer, the frequency of occurrence may be more." Chen Lijuan said, "This year's high temperature appeared early, and the expected end time is also late, and this 'start early, end late' feature will become more and more obvious in the future." ”
(Reporter Cui Xingyi)
Source: Guangming Daily