Xinhua News Agency, Beijing, August 13th: Experts analyze four major focuses of recent high temperature weather
Xinhua News Agency reporter Huang Yao
Since the beginning of summer this year, there have been many high-temperature days, wide coverage, and the highest temperature in many places breaking the historical extreme. The Central Meteorological Observatory continued to issue a high-temperature red warning on the 13th, and the China Meteorological Administration launched a high-temperature emergency response that day.
How extreme is the continuous high temperature weather?
What are the causes and effects?
Will it become the norm?
Focus 1: How is the recent high temperature weather?
Chen Tao, chief forecaster of the Central Meteorological Observatory, said that since late July, the middle and lower reaches of the Yangtze River and other places have experienced large-scale and strong high-temperature weather.
On August 12, the Central Meteorological Observatory issued the first high temperature red warning this year; as of the 13th, the Central Meteorological Observatory had issued a high temperature warning for 24 consecutive days.
The data shows that since July, the average number of high temperature days above 35°C in Zhejiang Province has been 31 days, and the average number of days above 38°C is 16 days, both of which are the most in the same period in history; the average number of high temperature days in Chongqing has reached 29.3 days, the second most in the same period since 1951. ; Shanghai has a total of 40 days with high temperature above 35°C this year, and 6 days with high temperature above 40°C.
Chen Lijuan, chief forecaster of the National Climate Center, said that the current regional high temperature process has not exceeded that of 2013, but the high temperature weather in the south will continue in the next two weeks.
According to forecasts, the duration of this regional high temperature process will exceed the 62 days in 2013, making it the longest high temperature process since 1961. The comprehensive intensity of high temperature weather this year may be the strongest since complete records began in 1961.
Focus 2: How long is the high temperature red warning expected to last?
According to Chen Tao, the standard for high temperature red warning issued by the Central Meteorological Observatory is: in the past 48 hours, the highest temperature in some areas of 4 or more provinces has continuously reached 40 °C and above, and the above-mentioned areas are expected to continue in the future.
"From the perspective of the forecast process on the 12th, first of all, according to monitoring, some areas of Sichuan, Chongqing, Zhejiang, Jiangsu and Hubei have experienced persistent high temperature weather above 40 °C. At the same time, through the analysis of atmospheric circulation, it is expected that in the future From the Sichuan Basin to the middle and lower reaches of the Yangtze River, there will still be large-scale and strong high-temperature weather." Chen Tao said that it is initially expected that the high-temperature weather in the next 4 to 5 days will still meet the issuance standards of the red warning, and the Central Meteorological Observatory will continue to Track the weather and forecast development, and update forecasts and early warnings in a timely manner.
Focus 3: What are the causes of persistent high temperature weather? Will it become the norm?
Chen Lijuan said that high temperature and heat wave events in summer are normal from a climatic point of view.
However, the duration, intensity and impact range of this summer's high temperature and heat wave events have reached a very strong level.
According to the monitoring and later forecast of the National Climate Center, the rare high-temperature weather in my country since June this year may reach the strongest high-temperature event since complete meteorological records were available in 1961.
According to Chen Lijuan's analysis, from the perspective of the most intuitive factor affecting temperature - the characteristics of atmospheric circulation, this year's Western Pacific subtropical high is anomalous strong and extending westward.
"Such high temperatures and heat waves like this year may occur more frequently in future summers." Chen Lijuan said that under the background of climate change, high temperature and heat wave events will become a norm.
In addition, this year's high temperature weather started early, ended late, and lasted for a long time. This feature may become more and more prominent in the future.
It is not only the frequent occurrence of high temperatures in my country, but since the beginning of summer, high temperature heat waves have occurred in many places in the northern hemisphere, and many cities in France, Spain, the United Kingdom, the United States, Japan and other countries have set new high temperature records.
The sixth assessment report of the United Nations Intergovernmental Panel on Climate Change (IPCC) pointed out that in the last 50 years, global warming has occurred at an unprecedented rate since the past 2000 years, and the instability of the climate system has increased.
Since the beginning of the 21st century, high temperature and heat waves in the northern hemisphere have become more frequent in summer.
Focus 4: How about the drought under the influence of high temperature?
Affected by the continuous high temperature and little rain, drought conditions in some areas of the Yangtze River Basin developed rapidly.
The Ministry of Water Resources issued a drought report on the 11th, saying that the 6 provinces and cities of Anhui, Jiangxi, Hubei, Hunan, Chongqing, and Sichuan affected 9.67 million mu of arable land, and 830,000 people were affected by the drought.
The Ministry of Water Resources launched a level IV emergency response to drought prevention for 6 provinces and cities, Anhui, Jiangxi, Hubei, Hunan, Chongqing and Sichuan.
The Ministry of Water Resources issued a notice to the relevant provincial and municipal water conservancy departments, requesting early adoption of drought-fighting measures to reduce the impact and losses of the drought.
At the same time, it organized the preparation of emergency water volume dispatching plans for the Yangtze River Basin, put forward dispatching measures for key arid areas, basin-by-basin, and planned the dispatching of 51 major reservoirs such as the Three Gorges and Danjiangkou in advance to reserve water sources for drought relief.
Chen Lijuan said that there is still a high possibility of less precipitation in the Yangtze River Basin in autumn, especially in the middle and lower reaches of the country, there may be consecutive droughts in summer and autumn.
The Meteorological Department will continue to strengthen monitoring and forecasting and revise forecasts in a timely manner.
In addition to the drought, some areas also experienced floods of varying degrees.
Recently, the Northeast region is in a critical period of flood control, and some rivers in the Songliao Basin continue to exceed the warning level. Affected by rainfall and high temperature snowmelt, 21 rivers such as the main stream of the Tarim River and its tributary, the Yarkand River, have floods that exceed the warning flow rate...
At present, it is still in the critical period of "seven down and eight up" flood control, and all localities should do a good job in flood and drought response work in advance.